1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705 2706 2707 2708 2709 2710 2711 2712 2713 2714 2715 2716 2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761 2762 2763 2764 2765 2766 2767 2768 2769 2770 2771 2772 2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783 2784 2785 2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819 2820 2821 2822 2823 2824 2825 2826 2827 2828 2829 2830 2831 2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847 2848 2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 2885 2886 2887 2888 2889 2890 2891 2892 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 2945 2946 2947 2948 2949 2950 2951 2952 2953 2954 2955 2956 2957 2958 2959 2960 2961 2962 2963 2964 2965 2966 2967 2968 2969 2970 2971 2972 2973 2974 2975 2976 2977 2978 2979 2980 2981 2982 2983 2984 2985 2986 2987 2988 2989 2990 2991 2992 2993 2994 2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018 3019 3020 3021 3022 3023 3024 3025 3026 3027 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046 3047 3048 3049 3050 3051 3052 3053 3054 3055 3056 3057 3058 3059 3060 3061 3062 3063 3064 3065 3066 3067 3068 3069 3070 3071 3072 3073 3074 3075 3076 3077 3078 3079 3080 3081 3082 3083 3084 3085 3086 3087 3088 3089 3090 3091 3092 3093 3094 3095 3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107 3108 3109 3110 3111 3112 3113 3114 3115 3116 3117 3118 3119 3120 3121 3122 3123 3124 3125 3126 3127 3128 3129 3130 3131 3132 3133 3134 3135 3136 3137 3138 3139 3140 3141 3142 3143 3144 3145 3146 3147 3148 3149 3150 3151 3152 3153 3154 3155 3156 3157 3158 3159 3160 3161 3162 3163 3164 3165 3166 3167 3168 3169 3170 3171 3172 3173 3174 3175 3176 3177 3178 3179 3180 3181 3182 3183 3184 3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197 3198 3199 3200 3201 3202 3203 3204 3205 3206 3207 3208 3209 3210 3211 3212 3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230 3231 3232 3233 3234 3235 3236 3237 3238 3239 3240 3241 3242 3243 3244 3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257 3258 3259 3260 3261 3262 3263 3264 3265 3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352 3353 3354 3355 3356 3357 3358 3359 3360 3361 3362 3363 3364 3365 3366 3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 3380 3381 3382 3383 3384 3385 3386 3387 3388 3389 3390 3391 3392 3393 3394 3395 3396 3397 3398 3399 3400 3401 3402 3403 3404 3405 3406 3407 3408 3409 3410 3411 3412 3413 3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 3425 3426 3427 3428 3429 3430 3431 3432 3433 3434 3435 3436 3437 3438 3439 3440 3441 3442 3443 3444 3445 3446 3447 3448 3449 3450 3451 3452 3453 3454 3455 3456 3457 3458 3459 3460 3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471 3472 3473 3474 3475 3476 3477 3478 3479 3480 3481 3482 3483 3484 3485 3486 3487 3488 3489 3490 3491 3492 3493 3494 3495 3496 3497 3498 3499 3500 3501 3502 3503 3504 3505 3506 3507 3508 3509 3510 3511 3512 3513 3514 3515 3516 3517 3518 3519 3520 3521 3522 3523 3524 3525 3526 3527 3528 3529 3530 3531 3532 3533 3534 3535 3536 3537 3538 3539 3540 3541 3542 3543 3544 3545 3546 3547 3548 3549 3550 3551 3552 3553 3554 3555 3556 3557 3558 3559 3560 3561 3562 3563 3564 3565 3566 3567 3568 3569 3570 3571 3572 3573 3574 3575 3576 3577 3578 3579 3580 3581 3582 3583 3584 3585 3586 3587 3588 3589 3590 3591 3592 3593 3594 3595 3596 3597 3598 3599 3600 3601 3602 3603 3604 3605 3606 3607 3608 3609 3610 3611 3612 3613 3614 3615 3616 3617 3618 3619 3620 3621 3622 3623 3624 3625 3626 3627 3628 3629 3630 3631 3632 3633 3634 3635 3636 3637 3638 3639 3640 3641 3642 3643 3644 3645 3646 3647 3648 3649 3650 3651 3652 3653 3654 3655 3656 3657 3658 3659 3660 3661 3662 3663 3664 3665 3666 3667 3668 3669 3670 3671 3672 3673 3674 3675 3676 3677 3678 3679 3680 3681 3682 3683 3684 3685 3686 3687 3688 3689 3690 3691 3692 3693 3694 3695 3696 3697 3698 3699 3700 3701 3702 3703 3704 3705 3706 3707 3708 3709 3710 3711 3712 3713 3714 3715 3716 3717 3718 3719 3720 3721 3722 3723 3724 3725 3726 3727 3728 3729 3730 3731 3732 3733 3734 3735 3736 3737 3738 3739 3740 3741 3742 3743 3744 3745 3746 3747 3748 3749 3750 3751 3752 3753 3754 3755 3756 3757 3758 3759 3760 3761 3762 3763 3764 3765 3766 3767 3768 3769 3770 3771 3772 3773 3774 3775 3776 3777 3778 3779 3780 3781 3782 3783 3784 3785 3786 3787 3788 3789 3790 3791 3792 3793 3794 3795 3796 3797 3798 3799 3800 3801 3802 3803 3804 3805 3806 3807 3808 3809 3810 3811 3812 3813 3814 3815 3816 3817 3818 3819 3820 3821 3822 3823 3824 3825 3826 3827 3828 3829 3830 3831 3832 3833 3834 3835 3836 3837 3838 3839 3840 3841 3842 3843 3844 3845 3846 3847 3848 3849 3850 3851 3852 3853 3854 3855 3856 3857 3858 3859 3860 3861 3862 3863 3864 3865 3866 3867 3868 3869 3870 3871 3872 3873 3874 3875 3876 3877 3878 3879 3880 3881 3882 3883 3884 3885 3886 3887 3888 3889 3890 3891 3892 3893 3894 3895 3896 3897 3898 3899 3900 3901 3902 3903 3904 3905 3906 3907 3908 3909 3910 3911 3912 3913 3914 3915 3916 3917 3918 3919 3920 3921 3922 3923 3924 3925 3926 3927 3928 3929 3930 3931 3932 3933 3934 3935 3936 3937 3938 3939 3940 3941 3942 3943 3944 3945 3946 3947 3948 3949 3950 3951 3952 3953 3954 3955 3956 3957 3958 3959 3960 3961 3962 3963 3964 3965 3966 3967 3968 3969 3970 3971 3972 3973 3974 3975 3976 3977 3978 3979 3980 3981 3982 3983 3984 3985 3986 3987 3988 3989 3990 3991 3992 3993 3994 3995 3996 3997 3998 3999 4000 4001 4002 4003 4004 4005 4006 4007 4008 4009 4010 4011 4012 4013 4014 4015 4016 4017 4018 4019 4020 4021 4022 4023 4024 4025 4026 4027 4028 4029 4030 4031 4032 4033 4034 4035 4036 4037 4038 4039 4040 4041 4042 4043 4044 4045 4046 4047 4048 4049 4050 4051 4052 4053 4054 4055 4056 4057 4058 4059 4060 4061 4062 4063 4064 4065 4066 4067 4068 4069 4070 4071 4072 4073 4074 4075 4076 4077 4078 4079 4080 4081 4082 4083 4084 4085 4086 4087 4088 4089 4090 4091 4092 4093 4094 4095 4096 4097 4098 4099 4100 4101 4102 4103 4104 4105 4106 4107 4108 4109 4110 4111 4112 4113 4114 4115 4116 4117 4118 4119 4120 4121 4122 4123 4124 4125 4126 4127 4128 4129 4130 4131 4132 4133 4134 4135 4136 4137 4138 4139 4140 4141 4142 4143 4144 4145 4146 4147 4148 4149 4150 4151 4152 4153 4154 4155 4156 4157 4158 4159 4160 4161 4162 4163 4164 4165 4166 4167 4168 4169 4170 4171 4172 4173 4174 4175 4176 4177 4178 4179 4180 4181 4182 4183 4184 4185 4186 4187 4188 4189 4190 4191 4192 4193 4194 4195 4196 4197 4198 4199 4200 4201 4202 4203 4204 4205 4206 4207 4208 4209 4210 4211 4212 4213 4214 4215 4216 4217 4218 4219 4220 4221 4222 4223 4224 4225 4226 4227 4228 4229 4230 4231 4232 4233 4234 4235 4236 4237 4238 4239 4240 4241 4242 4243 4244 4245 4246 4247 4248 4249 4250 4251 4252 4253 4254 4255 4256 4257 4258 4259 4260 4261 4262 4263 4264 4265 4266 4267 4268 4269 4270 4271 4272 4273 4274 4275 4276 4277 4278 4279 4280 4281 4282 4283 4284 4285 4286 4287 4288 4289 4290 4291 4292 4293 4294 4295 4296 4297 4298 4299 4300 4301 4302 4303 4304 4305 4306 4307 4308 4309 4310 4311 4312 4313 4314 4315 4316 4317 4318 4319 4320 4321 4322 4323 4324 4325 4326 4327 4328 4329 4330 4331 4332 4333 4334 4335 4336 4337 4338 4339 4340 4341 4342 4343 4344 4345 4346 4347 4348 4349 4350 4351 4352 4353 4354 4355 4356 4357 4358 4359 4360 4361 4362 4363 4364 4365
|
<pre>Internet Engineering Task Force (IETF) M. Barnes
Request for Comments: 6504 Polycom
Category: Informational L. Miniero
ISSN: 2070-1721 Meetecho
R. Presta
S P. Romano
University of Napoli
March 2012
<span class="h1">Centralized Conferencing Manipulation Protocol (CCMP)</span>
<span class="h1">Call Flow Examples</span>
Abstract
This document provides detailed call flows for the scenarios
documented in the Framework for Centralized Conferencing (XCON) (<a href="./rfc5239">RFC</a>
<a href="./rfc5239">5239</a>) and in the XCON scenarios (<a href="./rfc4597">RFC 4597</a>). The call flows document
the use of the interface between a conference control client and a
conference control server using the Centralized Conferencing
Manipulation Protocol (CCMP) (<a href="./rfc6503">RFC 6503</a>). The objective is to provide
detailed examples for reference by both protocol researchers and
developers.
Status of This Memo
This document is not an Internet Standards Track specification; it is
published for informational purposes.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Not all documents
approved by the IESG are a candidate for any level of Internet
Standard; see <a href="./rfc5741#section-2">Section 2 of RFC 5741</a>.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
<a href="http://www.rfc-editor.org/info/rfc6504">http://www.rfc-editor.org/info/rfc6504</a>.
Copyright Notice
Copyright (c) 2012 IETF Trust and the persons identified as the
document authors. All rights reserved.
<span class="grey">Barnes, et al. Informational [Page 1]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-2" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
This document is subject to <a href="https://www.rfc-editor.org/bcp/bcp78">BCP 78</a> and the IETF Trust's Legal
Provisions Relating to IETF Documents
(<a href="http://trustee.ietf.org/license-info">http://trustee.ietf.org/license-info</a>) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
<a href="#section-1">1</a>. Introduction ....................................................<a href="#page-3">3</a>
<a href="#section-2">2</a>. Terminology .....................................................<a href="#page-3">3</a>
<a href="#section-3">3</a>. Overview ........................................................<a href="#page-4">4</a>
<a href="#section-4">4</a>. Working with CCMP ...............................................<a href="#page-4">4</a>
<a href="#section-4.1">4.1</a>. CCMP and the Data Model ....................................<a href="#page-5">5</a>
<a href="#section-4.2">4.2</a>. Using HTTP/TLS as a Transport ..............................<a href="#page-6">6</a>
<a href="#section-4.3">4.3</a>. Conference Notifications ..................................<a href="#page-10">10</a>
<a href="#section-5">5</a>. Conference Creation ............................................<a href="#page-11">11</a>
<a href="#section-5.1">5.1</a>. Basic Conference Creation .................................<a href="#page-12">12</a>
<a href="#section-5.2">5.2</a>. Conference Creation Using Blueprints ......................<a href="#page-16">16</a>
5.3. Conference Creation Using User-Provided Conference
Information ...............................................<a href="#page-23">23</a>
<a href="#section-5.4">5.4</a>. Cloning an Existing Conference ............................<a href="#page-28">28</a>
<a href="#section-6">6</a>. Conference Users Scenarios and Examples ........................<a href="#page-31">31</a>
<a href="#section-6.1">6.1</a>. Adding a Party ............................................<a href="#page-32">32</a>
<a href="#section-6.2">6.2</a>. Muting a Party ............................................<a href="#page-35">35</a>
<a href="#section-6.3">6.3</a>. Conference Announcements and Recordings ...................<a href="#page-38">38</a>
<a href="#section-6.4">6.4</a>. Monitoring for DTMF .......................................<a href="#page-41">41</a>
<a href="#section-6.5">6.5</a>. Entering a Password-Protected Conference ..................<a href="#page-42">42</a>
<a href="#section-7">7</a>. Sidebars Scenarios and Examples ................................<a href="#page-44">44</a>
<a href="#section-7.1">7.1</a>. Internal Sidebar ..........................................<a href="#page-45">45</a>
<a href="#section-7.2">7.2</a>. External Sidebar ..........................................<a href="#page-54">54</a>
<a href="#section-7.3">7.3</a>. Private Messages ..........................................<a href="#page-60">60</a>
<a href="#section-7.4">7.4</a>. Observing and Coaching ....................................<a href="#page-64">64</a>
<a href="#section-8">8</a>. Removing Participants and Deleting Conferences .................<a href="#page-71">71</a>
<a href="#section-8.1">8.1</a>. Removing a Party ..........................................<a href="#page-71">71</a>
<a href="#section-8.2">8.2</a>. Deleting a Conference .....................................<a href="#page-74">74</a>
<a href="#section-9">9</a>. Security Considerations ........................................<a href="#page-75">75</a>
<a href="#section-10">10</a>. Acknowledgements ..............................................<a href="#page-76">76</a>
<a href="#section-11">11</a>. References ....................................................<a href="#page-76">76</a>
<a href="#section-11.1">11.1</a>. Normative References .....................................<a href="#page-76">76</a>
<a href="#section-11.2">11.2</a>. Informative References ...................................<a href="#page-76">76</a>
<span class="grey">Barnes, et al. Informational [Page 2]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-3" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<span class="h2"><a class="selflink" id="section-1" href="#section-1">1</a>. Introduction</span>
This document provides detailed call flows for the scenarios
documented in the Framework for Centralized Conferencing (XCON)
[<a href="./rfc5239" title=""A Framework for Centralized Conferencing"">RFC5239</a>] and in the XCON scenarios [<a href="./rfc4597" title=""Conferencing Scenarios"">RFC4597</a>]. The XCON scenarios
describe a broad range of use cases taking advantage of the advanced
conferencing capabilities provided by a system realization of the
XCON framework. The call flows document the use of the interface
between a conference control client and a conference control server
using the Centralized Conferencing Manipulation Protocol (CCMP)
[<a href="./rfc6503" title=""Centralized Conferencing Manipulation Protocol"">RFC6503</a>].
Due to the broad range of functionality provided by the XCON
framework and the flexibility of the CCMP messaging, these call flows
should not be considered inclusive of all the functionality that can
provided by the XCON framework and protocol implementations. These
flows represent a sample to provide an overview of the feature-rich
capabilities of the XCON framework and CCMP messaging for protocol
developers, software developers, and researchers.
<span class="h2"><a class="selflink" id="section-2" href="#section-2">2</a>. Terminology</span>
This document uses the same terminology as found in the Architectural
Framework for Media Server Control [<a href="./rfc5567" title=""An Architectural Framework for Media Server Control"">RFC5567</a>] and in the Media Control
Channel Framework Call Flow Examples [<a href="#ref-CALL-FLOWS">CALL-FLOWS</a>], with the following
terms and abbreviations used in the call flows. Also, note that the
term "call flows" is used in a very generic sense in this document
since the media is not limited to voice. The calls supported by the
XCON framework and CCMP can consist of media such as text, voice, and
video, including multiple media types in a single active conference.
Conference and Media Control Client (CMCC): as defined in the XCON
framework. In the flows in this document, the CMCC is logically
equivalent to the use of a User Agent Client (UAC) as the client
notation in the media control call flows [<a href="#ref-CALL-FLOWS">CALL-FLOWS</a>]. A CMCC
differs from a generic media client in being an XCON-aware entity,
thus, also being able to issue CCMP requests.
Conference Server (ConfS): In this document, the term "conference
server" is used interchangeably with the term "Application Server
(AS)" as used in the media control architectural framework
[<a href="./rfc5567" title=""An Architectural Framework for Media Server Control"">RFC5567</a>]. A conference server is intended to be able to act as a
conference control server, as defined in the XCON framework, i.e.,
it is able to handle CCMP requests and issue CCMP responses.
<span class="grey">Barnes, et al. Informational [Page 3]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-4" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
Media Server (MS): as defined in the media control architectural
framework [<a href="./rfc5567" title=""An Architectural Framework for Media Server Control"">RFC5567</a>].
<span class="h2"><a class="selflink" id="section-3" href="#section-3">3</a>. Overview</span>
This document provides a sampling of detailed call flows that can be
implemented based on a system realization of the XCON framework
[<a href="./rfc5239" title=""A Framework for Centralized Conferencing"">RFC5239</a>] and implementation of CCMP [<a href="./rfc6503" title=""Centralized Conferencing Manipulation Protocol"">RFC6503</a>]. This is intended to
be a simple guide for the use of the conference control protocol
between the conference server and the conference control client. The
objective is to provide an informational base reference for protocol
developers, software developers, and researchers.
This document focuses on the interaction between the conference and
media control client and the conferencing system, specifically the
conference server. The scenarios are based on those described in the
XCON framework, many of which are based on the advanced conferencing
capabilities described in the XCON scenarios. Additional scenarios
have been added to provide examples of other real-life scenarios that
are anticipated to be supported by the framework. With the exception
of an initial example with media control messaging, the examples do
not include the details for the media control [<a href="./rfc6505" title=""A Mixer Control Package for the Media Control Channel Framework"">RFC6505</a>], call
signaling, or Binary Floor Control Protocols (BFCPs) [<a href="./rfc4582" title=""The Binary Floor Control Protocol (BFCP)"">RFC4582</a>]. This
document references the scenarios in the media control call flows
[<a href="#ref-CALL-FLOWS">CALL-FLOWS</a>], SIP call control conferencing, [<a href="./rfc4579" title=""Session Initiation Protocol (SIP) Call Control - Conferencing for User Agents"">RFC4579</a>], and BFCP
documents.
The rest of this document is organized as follows. <a href="#section-4">Section 4</a>
presents an overview on CCMP, together with some implementation-
related details and related matters like HTTPS transport and
notifications. <a href="#section-5">Section 5</a> presents the reader with examples showing
the different approaches CCMP provides to create a new conference.
<a href="#section-6">Section 6</a> more generally addresses the different user-related
manipulations that can be achieved by means of CCMP, by presenting a
number of interesting scenarios. <a href="#section-7">Section 7</a> addresses several
scenarios that may involve the use of sidebars. <a href="#section-8">Section 8</a> shows how
CCMP can be used to remove conferences and users from the system.
Finally, <a href="#section-9">Section 9</a> provides a few details on the security
considerations when it comes to implementing CCMP.
<span class="h2"><a class="selflink" id="section-4" href="#section-4">4</a>. Working with CCMP</span>
This section provides a brief introduction as to how the Centralized
Conferencing Manipulation Protocol (CCMP) [<a href="./rfc6503" title=""Centralized Conferencing Manipulation Protocol"">RFC6503</a>] works and how it
can be transported across a network. A typical CCMP interaction
focusing on relevant aspects of the client-server communication is
<span class="grey">Barnes, et al. Informational [Page 4]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-5" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
described. Please note that this section assumes the reader has read
and understood the CCMP document. This section is intended to help
the reader understand the actual protocol interactions.
First, a description of the protocol itself is provided <a href="#section-4.1">Section 4.1</a>,
including some implementation considerations. In <a href="#section-4.2">Section 4.2</a>, an
effective CCMP interaction is presented by exploiting HTTPS as a
transport. Finally, notifications are described in <a href="#section-4.3">Section 4.3</a>.
The document then presents and describes some actual flows in detail
in the sections to follow.
<span class="h3"><a class="selflink" id="section-4.1" href="#section-4.1">4.1</a>. CCMP and the Data Model</span>
CCMP is an protocol based on XML [<a href="#ref-W3C.REC-xml-20081126">W3C.REC-xml-20081126</a>]. It has been
designed as a request/response protocol. It is completely stateless,
which means implementations can safely handle transactions
independently from each other.
The protocol allows for the manipulation of conference objects and
related users. This manipulation allows a conference and media
control client (briefly CMCC in all the following sections) to
create, update, and remove basically everything that is related to
the objects handled by a conferencing system. This is reflected in
the allowed operations (retrieve, create, update, delete) and the
specified request types (ranging from the manipulation of blueprints
and conferences to users and sidebars). For instance, CCMP provides
ways to:
o retrieve the list of registered and/or active conferences in the
system;
o create new conferences by exploiting several different approaches;
o add/remove users to/from a conference;
o update a conference with respect to all of its aspects;
and so on.
While CCMP acts as the means to manipulate conference objects, CCMP
does not define these conference objects. A separate document
specifies how a conference object and all its components have to be
constructed (Conference Information Data Model for Centralized
Conferencing (XCON) [<a href="./rfc6501" title=""Conference Information Data Model for Centralized Conferencing (XCON)"">RFC6501</a>]). CCMP, depending upon the request
type and the related operation, carries pieces of conference objects
(or any object as a whole) according to the aforementioned
<span class="grey">Barnes, et al. Informational [Page 5]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-6" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
specification. This means that any implementation aiming at being
compliant with CCMP has to make sure that the transported objects are
completely compliant with the data model specification and coherent
with the constraints defined therein. To make this clearer, there
are elements that are mandatory in a conference object: issuing a
syntactically correct CCMP request that carries a wrong conference
object is doomed to result in a failure. For this reason, it is
suggested that the interested implementers take special care in
carefully checking the data model handlers as well in order to avoid
potential mistakes.
However, there are cases when a mandatory element in the data model
cannot be assigned in a conference object by a CCMP user. For
example, a CMCC may be requesting the direct creation of a new
conference; in this case, a conference object assumes an 'entity'
attribute uniquely identifying the conference to be in place. Thus,
the CMCC has no way to know a priori what the entity will be, since
it is generated by the ConfS after the request. For scenarios like
this one, the CCMP specification describes the use of a dedicated
placeholder wildcard (i.e., "AUTO_GENERATE_X", where X is an integer)
to make the conference object compliant with the data model: the
wildcard would then be replaced by the ConfS with the right value.
<span class="h3"><a class="selflink" id="section-4.2" href="#section-4.2">4.2</a>. Using HTTP/TLS as a Transport</span>
CCMP requires that implementations support HTTP/TLS as the transport
mechanism. Per CCMP, a CMCC sends a request as part of an HTTPS POST
message, and the ConfS would reply with a 200 OK HTTPS response. In
both cases, the HTTPS messages carry the CCMP messages as payload,
which is reflected in the Content-Type header
("application/ccmp+xml"). Figure 1 presents a ladder diagram of such
an interaction, which is followed by a dump of the exchanged HTTPS
messages for further analysis. The examples in the remainder of this
document show only the CCMP interactions.
<span class="grey">Barnes, et al. Informational [Page 6]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-7" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
CMCC ConfS
| |
| 1. HTTPS POST (CCMP request) |
|--------------------------------------------->|
| |
| |--+ Parse request,
| | | update object
| |<-+ and reply
| |
| 2. 200 OK (CCMP response) |
|<---------------------------------------------|
| |
|--+ Parse response and |
| | update local copy |
|<-+ of conference object |
| |
' '
' '
Figure 1: CCMP on HTTPS
Per the protocol dump in the following lines, the CMCC has issued a
CCMP request (a blueprintRequest message asking for a blueprint
retrieval, i.e., with the <operation> element set to "retrieve" )
towards the ConfS. The request has been carried as payload of an
HTTPS POST (message 1.) towards a previously known location. The
mandatory Host header has been specified, and the Content-Type header
has been correctly set as well ("application/ccmp+xml").
The ConfS, in turn, has handled the request and replied accordingly.
The response (a blueprintResponse message with a <response-code> set
to a successful value, "200") has been carried as payload of a 200 OK
HTTPS response (message 2.). As before, the Content-Type header has
been correctly set ("application/ccmp+xml").
<span class="h2"><a class="selflink" id="section-1" href="#section-1">1</a>. CMCC -> ConfS (HTTPS POST, CCMP request)</span>
------------------------------------------
POST /Xcon/Ccmp HTTP/1.1
Content-Length: 657
Content-Type: application/ccmp+xml
Host: example.com:443
Connection: Keep-Alive
User-Agent: Apache-HttpClient/4.0.1 (java 1.5)
<span class="grey">Barnes, et al. Informational [Page 7]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-8" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-blueprint-request-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:AudioRoom@example.com</confObjID>
<operation>retrieve</operation>
<ccmp:blueprintRequest/>
</ccmpRequest>
</ccmp:ccmpRequest>
<span class="h2"><a class="selflink" id="section-2" href="#section-2">2</a>. CMCC <- ConfS (200 to POST, CCMP response)</span>
---------------------------------------------
HTTP/1.1 200 OK
X-Powered-By: Servlet/2.5
Server: Sun GlassFish Communications Server 1.5
Content-Type: application/ccmp+xml;charset=ISO-8859-1
Content-Length: 1652
Date: Thu, 04 Feb 2010 14:47:56 GMT
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-blueprint-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:AudioRoom@example.com</confObjID>
<operation>retrieve</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<ccmp:blueprintResponse>
<blueprintInfo entity="xcon:AudioRoom@example.com">
<info:conference-description>
<info:display-text>AudioRoom</info:display-text>
<info:maximum-user-count>2</info:maximum-user-count>
<info:available-media>
<info:entry label="audioLabel">
<info:type>audio</info:type>
</info:entry>
</info:available-media>
</info:conference-description>
<info:users>
<xcon:join-handling>allow</xcon:join-handling>
<span class="grey">Barnes, et al. Informational [Page 8]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-9" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
</info:users>
<xcon:floor-information>
<xcon:floor-request-handling>confirm
</xcon:floor-request-handling>
<xcon:conference-floor-policy>
<xcon:floor id="audioLabel"></xcon:floor>
</xcon:conference-floor-policy>
</xcon:floor-information>
</blueprintInfo>
</ccmp:blueprintResponse>
</ccmpResponse>
</ccmp:ccmpResponse>
For completeness, the following provides some details of the CCMP
interaction. Despite the simplicity of the request, this flow
provides some relevant information on how CCMP messages are built.
Specifically, both the CCMP request and the CCMP response share a
subset of the message:
o <confUserID>: this element, provided by the CMCC, refers to the
requester by means of his XCON-USERID; except in a few scenarios
(presented in the following sections), this element must always
contain a valid value;
o <confObjID>: this element refers to the target conference object,
according to the request in place;
o <operation>: this element specifies the operation the CMCC wants
to perform, according to the specific request type.
Besides those elements, the CMCC (let's say Alice, whose XCON-USERID
is "xcon-userid:Alice@example.com") has also provided an additional
element, <blueprintRequest>. The name of that element varies
according to the request type in which the CMCC is interested. In
this specific scenario, the CMCC was interested in acquiring details
concerning a specific blueprint (identified by its XCON-URI
"xcon:AudioRoom@example.com", as reflected in the provided
<confObjID> target element), and so the request consisted in an empty
<blueprintRequest> element. It will be clearer in the following
sections that different request types may require different elements
and, as a consequence, different content.
Considering the request was a blueprintRequest message, the ConfS has
replied with a blueprintResponse message containing a
<blueprintResponse> element. This element includes a complete dump
of the conference object (compliant with the data model) describing
the requested blueprint.
<span class="grey">Barnes, et al. Informational [Page 9]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-10" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
Without providing additional details of this interaction, it is worth
noting that this was the example of the simplest CCMP communication
that could take place between a CMCC and a ConfS, a blueprint
request: this scenario will be described in more detail in
<a href="#section-5.2">Section 5.2</a>.
<span class="h3"><a class="selflink" id="section-4.3" href="#section-4.3">4.3</a>. Conference Notifications</span>
The XCON framework [<a href="./rfc5239" title=""A Framework for Centralized Conferencing"">RFC5239</a>] identifies several different possible
protocol interactions between a conference server and a conferencing
client. One of those interactions is generically called
"notification protocol" providing a mechanism for all clients
interested in being informed by the server whenever something
relevant happens in a conference. When SIP is used as the call
signaling protocol in a CCMP implementation, the XCON event package
[<a href="./rfc6502" title=""Conference Event Package Data Format Extension for Centralized Conferencing (XCON)"">RFC6502</a>], which extends the SIP event package for conference state
[<a href="./rfc4575" title=""A Session Initiation Protocol (SIP) Event Package for Conference State"">RFC4575</a>] must be supported. A SIP client uses the SIP SUBSCRIBE
message for the XCON event package to subscribe to notifications
related to a specific conference. A SIP client would receive
notifications describing all the changes to the document via a SIP
NOTIFY message. An example ladder diagram is presented in Figure 2;
in this figure, we assume a CMCC has updated a conference object, and
a previously subscribed SIP client is notified of the update.
<span class="grey">Barnes, et al. Informational [Page 10]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-11" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
CMCC ConfS UAC
| | |
| | 1. SIP SUBSCRIBE |
| |<--------------------------|
| Handle +--| |
| new | | |
| subscription +->| 2. SIP 200 OK |
| |-------------------------->|
| | |
' ' '
' ' '
| | |
| 3. CCMP (add user) | |
|---------------------->| |
| |--+ Add user |
| | | to conf. |
| |<-+ object |
| 4. CCMP (success) | |
|<----------------------| |
| | 5. SIP NOTIFY (changes) |
| |-------------------------->|
| | 6. SIP 200 OK |
| |<--------------------------|
| | |
' ' '
' ' '
Figure 2: XCON Event Package: SIP Notifications
The detailed flows in this document generically present a
notification, when appropriate, but do not include the SIP messaging
details.
<span class="h2"><a class="selflink" id="section-5" href="#section-5">5</a>. Conference Creation</span>
This section provides details associated with the various ways in
which a conference can be created using CCMP and the XCON framework
constructs. As previously mentioned, the details of the media
control, call signaling, and floor control protocols, where
applicable, are annotated in the flows without showing all the
details. This also applies to CCMP, whose flows are related to the
protocol alone, hiding any detail concerning the transport that may
have been used (e.g., HTTPS). However, for clarification purposes,
the first example in <a href="#section-5.1">Section 5.1</a> provides the details of the media
control messaging with the standard annotation used throughout the
remainder of this document. In subsequent flows, only this
<span class="grey">Barnes, et al. Informational [Page 11]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-12" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
annotation (identified by lowercase letters) is included, and the
reader is encouraged to refer to the call flows in the relevant
documents for details about the other protocols. The annotations for
the call signaling are on the left side of the conference server
vertical bar, and those for the media control messaging are on the
right side.
<span class="h3"><a class="selflink" id="section-5.1" href="#section-5.1">5.1</a>. Basic Conference Creation</span>
The simplest manner in which a conference can be created is
accomplished by the client sending a confRequest message with the
<operation> element set to "create" as the only parameter to the
conference server, together with the <confUserID> associated with the
requesting client itself. This results in the creation of a default
conference, with an XCON-URI in the form of the <confObjID> element,
the XCON-USERID in the form of the <confUserID> element (the same one
already present in the request), and the data for the conference
object in the <confInfo> parameter all returned in the confResponse
message. This example also adds the issuing user to the conference
upon creation with the 'method' attribute in the <target> child
element of <allowed-users-list> set to "dial-out".
The specific data for the conference object is returned in the
confResponse message in the <confInfo> parameter. This allows the
client (with the appropriate authorization) to manipulate these data
and add additional participants to the conference, as well as change
the data during the conference. In addition, the client may
distribute the conferencing information to other participants
allowing them to join, the details of which are provided in
additional flows. Please notice that, according to the CCMP
specification, the return of the new conference data in the
<confInfo> element is not mandatory: if the <confInfo> parameter of
is not included in the successful confResponse/create message, a
subsequent confRequest/retrieve message of the returned <confObjID>
can be triggered to provide the requesting client with the detailed
conference description.
Clients that are not XCON-aware can join the conference using a
specific signaling interface such as SIP [<a href="./rfc3261" title=""SIP: Session Initiation Protocol"">RFC3261</a>] (using the
signaling interface to the conference focus as described in
[<a href="./rfc4579" title=""Session Initiation Protocol (SIP) Call Control - Conferencing for User Agents"">RFC4579</a>]), or other supported signaling protocols, being XCON-
agnostic with respect to them. However, these details are not shown
in the message flows. The message flows in this document identify
the point in the message flows at which this signaling occurs via the
lowercase letter items (i.e., (a)...(x)) along with the appropriate
text for the processing done by the conference server.
<span class="grey">Barnes, et al. Informational [Page 12]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-13" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
As previously described, this example also shows how the conferencing
system may make use of other standard protocol components for
complete functionality. An example of that is the media control
framework [<a href="./rfc5567" title=""An Architectural Framework for Media Server Control"">RFC5567</a>], which allows the conferencing system to
configure conference mixes, Interactive Voice Response (IVR) dialogs,
and all sorts of media-related interactions an application like this
may need. In order to provide the reader with some insight on these
interactions, the conference server in this example also configures
and starts a mixer via a media control channel as soon as the
conference is created (transactions A1 and A2), and attaches clients
to it when necessary (e.g., when CMCC1 joins the conference by means
of SIP signaling, its media channels are attached to the media server
(MS) in B1/B2). Note, that the media control interfaces are NOT
shown in the remaining call flows in this document but rather follow
the same annotation as with the SIP signaling such that (b)
correlates with the A1 and A2 transactions and (d) correlates with
the B1 and B2 transactions.
<span class="grey">Barnes, et al. Informational [Page 13]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-14" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
CMCC1 CMCC2 CMCCx ConfS MS
| | | | |
|(1)confRequest(confUserID, create) | |
|-------------------------------------->| |
| | (a)Create +---| |
| | |Conf | | |
| | |Object | | |
| | |& IDs +-->| |
| | | | A1. CONTROL |
| | | |+++++++++++>>|
| | | |(create conf)|--+ (b)
| | | | | | create
| | | | | | conf and
| | | | A2. 200 OK |<-+ its ID
| | | |<<+++++++++++|
| | | |(confid=Y) |
|(2)confResponse(confUserID,confObjID, | |
| create, 200, success, | |
| version, confInfo) | |
|<--------------------------------------| |
| | | | |
| | (c) Focus +---| |
| | sets up | | |
| | signaling | | |
| | to CMCC1 +-->| |
| | | | |
| | | | B1. CONTROL |
| | | |+++++++++++>>|
| | | | (join CMCC1 |
| | | | <->confY) |
| | | | |
| | | | |--+(d) join
| | | | | | CMCC1 &
| | | | B2.200 OK |<-+ conf Y
| | | |<<+++++++++++|
| | | | |
|<<#################################################>>|
| Now the CMCC1 is mixed in the conference |
|<<#################################################>>|
| | | | |
|******CMCC1 may then manipulate conference data *****|
|****** and add addt'l users, etc. | *****|
' ' ' ' '
' ' ' ' '
' ' ' ' '
Figure 3: Create Basic Conference - Complete flow
<span class="grey">Barnes, et al. Informational [Page 14]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-15" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<span class="h2"><a class="selflink" id="section-1" href="#section-1">1</a>. confRequest/create message (Alice creates a default conference)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpRequest
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-conf-request-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<operation>create</operation>
<ccmp:confRequest/>
</ccmpRequest>
</ccmp:ccmpRequest>
<span class="h2"><a class="selflink" id="section-2" href="#section-2">2</a>. confResponse/create message ("success", created conference</span>
<span class="h2"> object returned)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<ccmpResponse
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-conf-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8977794@example.com</confObjID>
<operation>create</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<version>1</version>
<ccmp:confResponse>
<confInfo entity="xcon:8977794@example.com">
<info:conference-description>
<info:display-text>
Default conference initiated by Alice
</info:display-text>
<info:conf-uris>
<info:entry>
<info:uri>
xcon:8977794@example.com
</info:uri>
<info:display-text>
Conference XCON-URI
</info:display-text>
<span class="grey">Barnes, et al. Informational [Page 15]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-16" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
</info:entry>
</info:conf-uris>
<info:maximum-user-count>10
</info:maximum-user-count>
<info:available-media>
<info:entry label="11">
<info:type>audio</info:type>
</info:entry>
</info:available-media>
</info:conference-description>
<info:conference-state>
<info:active>false</info:active>
</info:conference-state>
<info:users>
<xcon:join-handling>allow</xcon:join-handling>
<xcon:allowed-users-list>
<xcon:target uri="xcon-userid:Alice@example.com"
method="dial-out"/>
</xcon:allowed-users-list>
</info:users>
</confInfo>
</ccmp:confResponse>
</ccmpResponse>
</ccmp:ccmpResponse>
Figure 4: Create Basic Conference Detailed Messaging
<span class="h3"><a class="selflink" id="section-5.2" href="#section-5.2">5.2</a>. Conference Creation Using Blueprints</span>
The previous example showed the creation of a new conference using
default values. This means the client provided no information about
how she wanted the conference to be created. The XCON framework (and
CCMP as a consequence) allows for the implementation of templates.
These templates are called "conference blueprints" and are basically
conference objects with predefined settings. This means that a
client might get a list of blueprints, choose the one that most fits
his needs, and use the chosen blueprint to create a new conference.
Figure 5 provides an example of one client, Alice, discovering the
conference blueprints available for a particular conferencing system
and creating a conference based on the desired blueprint. In
particular, Alice is interested in those blueprints suitable to
represent a video conference, i.e., a conference in which both audio
and video are available, so she makes use of the filter mechanism
provided by CCMP to make a selective blueprints retrieve request.
This results in three distinct CCMP transactions.
<span class="grey">Barnes, et al. Informational [Page 16]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-17" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
CMCC Alice ConfS
| |
| (1) blueprintsRequest |
| (confUserID,xpathFilter) |
|------------------------------>|
| |
| (2) blueprintsResponse |
| (confUserID, |
| 200, success, |
| blueprintsInfo) |
| |
|<------------------------------|
| |
|--+ |
| | choose preferred |
| | blueprint from the |
| | list (blueprintName) |
|<-+ |
| |
| (3) blueprintRequest |
| (confUserID,confObjID, |
| retrieve) |
|------------------------------>|
| |
| 4) blueprintResponse |
| (confUserID,confObjID,|
| retrieve, 200, |
| success, confInfo) |
|<------------------------------|
| |
| (5) confRequest(confUserID, |
| confObjID,create) |
|------------------------------>|
| |
| (a)Create +---|
| Conf | |
| Object | |
| & IDs +-->|
| |--+ (b) MS
| | | creates
| | | conf and
| |<-+ its ID
| | (confid=Y)
|(6) confResponse |
| (confUserID, confObjID*, |
| create, 200, success) |
|<------------------------------|
| |
<span class="grey">Barnes, et al. Informational [Page 17]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-18" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
| |
| |
' '
' '
Figure 5: Client Creation of Conference Using Blueprints
1. Alice first sends a blueprintsRequest message to the conference
server identified by the conference server discovery process.
This request contains the <confUserID> set to the XCON-USERID of
the user issuing the request (in this case, the one belonging to
Alice) and the <xpathFilter> element by which Alice specifies she
desires to obtain only blueprints providing support for both
audio and video: for this purpose, the xpath query contained in
this field is: "/conference-info[conference-description/
available-media/entry/type='audio' and conference-description/
available-media/entry/type='video']". Upon receipt of the
blueprintsRequest message, the conference server would first
ensure, on the basis of the <confUserID> parameter, that Alice
has the appropriate authority based on system policies to receive
the requested kind of blueprints supported by that system.
2. All blueprints that Alice is authorized to use are returned in a
blueprintsResponse message in the <blueprintsInfo> element.
3. Upon receipt of the blueprintsResponse message containing the
blueprints, Alice determines which blueprint to use for the
conference to be created. Alice sends a blueprintRequest message
to get the specific blueprint as identified by the <confObjID>.
4. The conference server returns the details associated with the
specific blueprint identified by the <confObjID> in the
<confInfo> element within the blueprintResponse message.
5. Alice finally sends a confRequest message with a "create"
<operation> to the conference server to create a conference
reservation cloning the chosen blueprint. This is achieved by
writing the blueprint's XCON-URI in the <confObjID> parameter.
6. Upon receipt of the confRequest/create message, the conference
server uses the received blueprint to clone a conference,
allocating a new XCON-URI (called "confObjID*" in the example).
The conference server then sends a confResponse message including
the new "confObjID*" associated with the newly created conference
instance as the value of the <confObjID> parameter. Upon receipt
of the confResponse message, Alice can now add other users to the
conference.
<span class="grey">Barnes, et al. Informational [Page 18]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-19" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
1. blueprintsRequest message (Alice requires the list of the
available blueprints with video support)
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-blueprints-request-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<ccmp:blueprintsRequest>
<xpathFilter>/conference-info[conference-description/
available-media/entry/type='audio'
and
conference-description/available-media/entry/type='video']
</xpathFilter>
</ccmp:blueprintsRequest>
</ccmpRequest>
</ccmp:ccmpRequest>
<span class="h2"><a class="selflink" id="section-2" href="#section-2">2</a>. blueprintsResponse message (the server provides a</span>
<span class="h2"> descriptions of the available blueprints</span>
fitting Alice's request)
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<ccmpResponse
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-blueprints-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<response-code>200</response-code>
<response-string>success</response-string>
<ccmp:blueprintsResponse>
<blueprintsInfo>
<info:entry>
<info:uri>xcon:VideoRoom@example.com</info:uri>
<info:display-text>VideoRoom</info:display-text>
<info:purpose>Video Room:
conference room with public access,
where both audio and video are available,
4 users can talk and be seen at the same time,
and the floor requests are automatically accepted.
</info:purpose>
</info:entry>
<info:entry>
<span class="grey">Barnes, et al. Informational [Page 19]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-20" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<info:uri>xcon:VideoConference1@example.com</info:uri>
<info:display-text>VideoConference1</info:display-text>
<info:purpose>Public Video Conference: conference
where both audio and video are available,
only one user can talk
</info:purpose>
</info:entry>
</blueprintsInfo>
</ccmp:blueprintsResponse>
</ccmpResponse>
</ccmp:ccmpResponse>
<span class="h2"><a class="selflink" id="section-3" href="#section-3">3</a>. blueprintRequest/retrieve message (Alice wants the</span>
"VideoRoom" blueprint)
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-blueprint-request-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:VideoRoom@example.com</confObjID>
<operation>retrieve</operation>
<ccmp:blueprintRequest/>
</ccmpRequest>
</ccmp:ccmpRequest>
<span class="h2"><a class="selflink" id="section-4" href="#section-4">4</a>. blueprintResponse/retrieve message ("VideoRoom"</span>
<span class="h2"> conference object returned)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-blueprint-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:VideoRoom@example.com</confObjID>
<operation>retrieve</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<ccmp:blueprintResponse>
<blueprintInfo entity="xcon:VideoRoom@example.com">
<info:conference-description>
<info:display-text>VideoRoom</info:display-text>
<span class="grey">Barnes, et al. Informational [Page 20]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-21" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<info:maximum-user-count>4</info:maximum-user-count>
<info:available-media>
<info:entry label="audioLabel">
<info:type>audio</info:type>
</info:entry>
<info:entry label="videoLabel">
<info:type>video</info:type>
</info:entry>
</info:available-media>
</info:conference-description>
<info:users>
<xcon:join-handling>allow</xcon:join-handling>
</info:users>
<xcon:floor-information>
<xcon:floor-request-handling>confirm
</xcon:floor-request-handling>
<xcon:conference-floor-policy>
<xcon:floor id="audioFloor">
<xcon:media-label>audioLabel</xcon:media-label>
</xcon:floor>
<xcon:floor id="videoFloor">
<xcon:media-label>videoLabel</xcon:media-label>
</xcon:floor>
</xcon:conference-floor-policy>
</xcon:floor-information>
</blueprintInfo>
</ccmp:blueprintResponse>
</ccmpResponse>
</ccmp:ccmpResponse>
<span class="h2"><a class="selflink" id="section-5" href="#section-5">5</a>. confRequest/create message (Alice clones the "VideoRoom" blueprint)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpRequest
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-conf-request-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:VideoRoom@example.com</confObjID>
<operation>create</operation>
<ccmp:confRequest/>
</ccmpRequest>
</ccmp:ccmpRequest>
<span class="grey">Barnes, et al. Informational [Page 21]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-22" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<span class="h2"><a class="selflink" id="section-6" href="#section-6">6</a>. confResponse/create message (cloned conference</span>
<span class="h2"> object returned)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<ccmpResponse
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-conf-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8977794@example.com</confObjID>
<operation>create</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<version>1</version>
<ccmp:confResponse>
<confInfo entity="xcon:8977794@example.com">
<info:conference-description>
<info:display-text>
New conference by Alice cloned from VideoRoom
</info:display-text>
<info:conf-uris>
<info:entry>
<info:uri>
xcon:8977794@example.com
</info:uri>
<info:display-text>
conference xcon-uri
</info:display-text>
<xcon:conference-password>
8601
</xcon:conference-password>
</info:entry>
</info:conf-uris>
<info:maximum-user-count>10</info:maximum-user-count>
<info:available-media>
<info:entry label="11">
<info:type>audio</info:type>
</info:entry>
<info:entry label="12">
<info:type>video</info:type>
</info:entry>
</info:available-media>
</info:conference-description>
<info:users>
<xcon:join-handling>allow</xcon:join-handling>
<span class="grey">Barnes, et al. Informational [Page 22]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-23" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
</info:users>
<xcon:floor-information>
<xcon:floor-request-handling>
confirm</xcon:floor-request-handling>
<xcon:conference-floor-policy>
<xcon:floor id="1">
<xcon:media-label>11</xcon:media-label>
</xcon:floor>
<xcon:floor id="2">
<xcon:media-label>12</xcon:media-label>
</xcon:floor>
</xcon:conference-floor-policy>
</xcon:floor-information>
</confInfo>
</ccmp:confResponse>
</ccmpResponse>
</ccmp:ccmpResponse>
Figure 6: Create Conference (Blueprint) Detailed Messaging
<span class="h3"><a class="selflink" id="section-5.3" href="#section-5.3">5.3</a>. Conference Creation Using User-Provided Conference Information</span>
A conference can also be created by the client sending a confRequest
message with the "create" <operation>, along with the desired data in
the form of the <confInfo> element for the conference to be created.
The request also includes the <confUserID> set to the XCON-USERID of
the requesting entity.
This approach allows for a client (in this example Alice) to
completely describe what the conference object should look like,
without relying on defaults or blueprints; for example, which media
should be available, the topic, the users allowed to join, any
scheduling-related information, and so on. This can be done by
providing, in the creation request, a full conference object for the
server to parse.
This <confInfo> parameter must comply with the data model
specification. This means that the 'entity' attribute is mandatory
and cannot be missing in the document. However, in this example, the
client is actually requesting the creation of a new conference, which
doesn't exist yet, so the 'entity' attribute is unknown. As
discussed in <a href="#section-4.1">Section 4.1</a>, CCMP allows for the use of a wildcard
placeholder. This placeholder ("xcon:AUTO_GENERATE_1@example.com" in
the example) is only to ensure the <confInfo> element is compliant
with the data model and would subsequently be replaced by the
conference server with the actual value. Thus, when the conference
server actually creates the conference, a valid value for the
'entity' attribute is created for it as well, which takes the place
<span class="grey">Barnes, et al. Informational [Page 23]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-24" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
of the wildcard value when the actual conference object provided by
the client is populated.
To give a flavor of what could be added to the conference object, we
assume Alice is also interested in providing scheduling-related
information. So, in this example, Alice also specifies by the
<conference-time> element included in the <confInfo> that the
conference she wants to create has to occur on a certain date
spanning from a certain start time to a certain stop time and has to
be replicated weekly.
Moreover, Alice indicates by means of the <allowed-users-list>
element that at the start time Bob, Carol, and herself have to be
called by the conferencing system to join the conference (in fact,
for each <target> field corresponding to one of the aforementioned
clients, the 'method' attribute is set to "dial-out").
Once Alice has prepared the <confInfo> element and sent it as part of
her request to the server, if the conferencing system can support
that specific type of conference (capabilities, etc.), then the
request results in the creation of a conference. We assume the
request has been successful, and as a consequence, the XCON-URI in
the form of the <confObjID> parameter and the XCON-USERID in the form
of the <confUserID> parameter (again, the same as the requesting
entity) are returned in the confResponse message.
In this example, the created conference object is not returned in the
successful confResponse message in the <confInfo> parameter.
Nevertheless, Alice could still retrieve the actual conference object
by issuing a confRequest message with a "retrieve" <operation> on the
XCON-URI returned in the <confObjID> of the previous response. Such
a request would show how, as described at the beginning of this
section, the 'entity' attribute of the conference object in the
<confInfo> field is replaced with the actual information (i.e.,
"xcon:6845432@example.com").
<span class="grey">Barnes, et al. Informational [Page 24]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-25" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
Alice Bob Carol ConfS
| | | |
| | | |
|(1)confRequest(confUserID, | |
| create, confInfo) | |
| | | |
|-------------------------------------->|
| | | |
| | (a)Create +---|
| | |Conf | |
| | |Object | |
| | |& IDs +-->|
| | | |--+ (b) MS
| | | | | creates
| | | | | conf and
| | | |<-+ its ID
| | | | (confid=Y)
|(2)confResponse(confUserID,| |
| confObjID, create, | |
| 200, success, version) |
|<--------------------------------------|
| | | |
===========================================
... ... ... ...
========== START TIME OCCURS ==============
| | (c) Focus +---|
| | sets up | |
| | signaling | |
| | to Alice +-->|
| | | |
| | | |--+(d) MS joins
| | | | | Alice &
| | | |<-+ conf Y
| | | |
| | | |
|<<###################################>>|
| Alice is mixed in the conference |
|<<###################################>>|
| | | |
| | (e)Focus +---|
| | sets up | |
| | signaling | |
| | to Bob | |
| | | +-->|
| | | |
| | | |--+(f)MS joins
| | | | | Bob &
| | | |<-+ conf Y
<span class="grey">Barnes, et al. Informational [Page 25]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-26" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
| | | |
| |<<###################>>|
| | Bob is mixed too |
| |<<###################>>|
| | | |
| | (g )Focus +---|
| | sets up | |
| | signaling | |
| | to Carol | |
| | CMCCx +-->|
| | | |
| | | |--+(h)MS joins
| | | | | CMCCx &
| | | |<-+ conf Y
| | | |
| | |<<#######>>|
| | |Carol mixed|
| | |<<#######>>|
| | | |
| | | |
| | | |
|<***All parties connected to conf Y***>|
| | | |
| | | |
' ' ' '
' ' ' '
' ' ' '
Figure 7: Create Basic Conference from User-Provided Conference Info
1. confRequest/create message (Alice proposes a conference object
to be created)
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpRequest
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-conf-request-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<operation>create</operation>
<ccmp:confRequest>
<confInfo entity="xcon:AUTO_GENERATE_1@example.com">
<info:conference-description>
<info:display-text>
Dial-out conference initiated by Alice
<span class="grey">Barnes, et al. Informational [Page 26]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-27" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
</info:display-text>
<info:maximum-user-count>10</info:maximum-user-count>
<info:available-media>
<info:entry label="AUTO_GENERATE_2">
<info:type>audio</info:type>
</info:entry>
</info:available-media>
<xcon:conference-time>
<xcon:entry>
<xcon:base>
BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Mozilla.org/NONSGML
Mozilla Calendar V1.0//EN
BEGIN:VEVENT
DTSTAMP: 20100127T140728Z
UID: 20100127T140728Z-345FDA-alice@example.com
ORGANIZER:MAILTO:alice@example.com
DTSTART:20100127T143000Z
RRULE:FREQ=WEEKLY
DTEND: 20100127T163000Z
END:VEVENT
END:VCALENDAR
</xcon:base>
<xcon:mixing-start-offset
required-participant="moderator">
2010-01-27T14:29:00Z
</xcon:mixing-start-offset>
<xcon:mixing-end-offset
required-participant="participant">
2010-01-27T16:31:00Z
</xcon:mixing-end-offset>
<xcon:must-join-before-offset>
2010-01-27T15:30:00Z
</xcon:must-join-before-offset>
</xcon:entry>
</xcon:conference-time>
</info:conference-description>
<info:users>
<xcon:join-handling>allow</xcon:join-handling>
<xcon:allowed-users-list>
<xcon:target uri="xcon-userid:alice@example.com"
method="dial-out"/>
<xcon:target uri="sip:bob83@example.com"
method="dial-out"/>
<xcon:target uri="sip:carol@example.com"
method="dial-out"/>
</xcon:allowed-users-list>
<span class="grey">Barnes, et al. Informational [Page 27]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-28" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
</info:users>
</confInfo>
</ccmp:confRequest>
</ccmpRequest>
</ccmp:ccmpRequest>
2. confResponse/create message ("200", "success")
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<ccmpResponse
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-conf-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:6845432@example.com</confObjID>
<operation>create</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<version>1</version>
<ccmp:confResponse/>
</ccmpResponse>
</ccmp:ccmpResponse>
Figure 8: Create Basic Conference Detailed Messaging
<span class="h3"><a class="selflink" id="section-5.4" href="#section-5.4">5.4</a>. Cloning an Existing Conference</span>
A client can also create another conference by cloning an existing
conference, such as an active conference or conference reservation.
This approach can be seen as a logical extension of the creation of a
new conference using a blueprint: the difference is that, instead of
cloning the predefined settings listed in a blueprint, the settings
of an existing conference would be cloned.
In this example, the client sends a confRequest message with the
"create" <operation>, along with her XCON-USERID in the <confUserID>
element and the XCON-URI of the conference from which a new
conference is to be cloned in the <confObjID> element.
An example of how a client can create a conference based on a
blueprint is provided in <a href="#section-5.2">Section 5.2</a>. The manner by which a client
in this example might learn about a conference reservation or active
conferences is similar to the first step in the blueprint example,
with the exception of querying for different types of conference
<span class="grey">Barnes, et al. Informational [Page 28]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-29" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
objects supported by the specific conferencing system. For instance,
in this example, the client clones a conference reservation (i.e., an
inactive conference).
If the conferencing system can support a new instance of the specific
type of conference (capabilities, etc.), then the request results in
the creation of a conference, with an XCON-URI in the form of a new
value in the <confObjID> parameter to reflect the newly cloned
conference object returned in the confResponse message.
Alice ConfS
| |
|(1)confRequest(confUserID, |
| confObjID, create) |
|------------------------------>|
| (a)Create +---|
| Conf | |
| Object | |
| & IDs +-->|
| |--+ (b) MS
| | | creates
| | | conf and
| |<-+ its ID
| | (confid=Y)
| |
|(2)confResponse(confUserID, |
| confObjID*,create, |
| 200, success, |
| version, confInfo) |
| |
|<------------------------------|
| |
' '
Figure 9: Create Basic Conference - Clone
1. Alice, a conferencing system client, sends a confRequest message
to clone a conference based on an existing conference
reservation. Alice indicates this conference should be cloned
from the specified parent conference represented by the XCON-URI
in the <confObjID> provided in the request.
2. Upon receipt of the confRequest message containing a "create"
<operation> and the aforementioned XCON-URI in the <confObjID>,
the conference server ensures that such received XCON-URI is
valid. The conference server determines the appropriate read/
write access of any users to be added to a conference based on
this XCON-URI (using membership, roles, etc.). The conference
<span class="grey">Barnes, et al. Informational [Page 29]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-30" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
server uses the received <confObjID> to clone a conference
reservation. The conference server also reserves or allocates a
new XCON-URI (called "confObjID*" in Figure 9) to be used for the
cloned conference object. This new identifier is, of course,
different from the one associated with the conference to be
cloned, since it represents a different conference object. Any
subsequent protocol requests from any of the members of the
conference must use this new identifier. The conference server
maintains the mapping between this conference ID and the parent
conference object ID associated with the reservation through the
conference instance, and this mapping is explicitly addressed
through the <cloning-parent> element of the <conference-
description> in the new conference object.
<span class="h2"><a class="selflink" id="section-1" href="#section-1">1</a>. confRequest/create message (Alice clones an existing conference)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpRequest
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-conf-request-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:6845432@example.com</confObjID>
<operation>create</operation>
<ccmp:confRequest/>
</ccmpRequest>
</ccmp:ccmpRequest>
<span class="h2"><a class="selflink" id="section-2" href="#section-2">2</a>. confResponse/create message (created conference</span>
<span class="h2"> object returned)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<ccmpResponse
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-conf-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8977794@example.com</confObjID>
<operation>create</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<version>1</version>
<span class="grey">Barnes, et al. Informational [Page 30]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-31" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<ccmp:confResponse>
<confInfo entity="xcon:8977794@example.com">
<info:conference-description>
<info:display-text>
New conference by Alice cloned from 6845432
</info:display-text>
<info:maximum-user-count>10</info:maximum-user-count>
<info:available-media>
<info:entry label="11">
<info:type>audio</info:type>
</info:entry>
</info:available-media>
<xcon:cloning-parent>
xcon:6845432@example.com
</xcon:cloning-parent>
</info:conference-description>
<info:users>
<xcon:join-handling>allow</xcon:join-handling>
<xcon:allowed-users-list>
<xcon:target uri="sip:alice@example.com"
method="dial-out"/>
<xcon:target uri="sip:bob83@example.com"
method="dial-out"/>
<xcon:target uri="sip:carol@example.com"
method="dial-out"/>
</xcon:allowed-users-list>
</info:users>
<xcon:floor-information>
<xcon:floor-request-handling>
confirm</xcon:floor-request-handling>
<xcon:conference-floor-policy>
<xcon:floor id="1">
<xcon:media-label>11</xcon:media-label>
</xcon:floor>
</xcon:conference-floor-policy>
</xcon:floor-information>
</confInfo>
</ccmp:confResponse>
</ccmpResponse>
</ccmp:ccmpResponse>
Figure 10: Create Basic Conference (Clone) Detailed Messaging
<span class="h2"><a class="selflink" id="section-6" href="#section-6">6</a>. Conference Users Scenarios and Examples</span>
<a href="#section-5">Section 5</a> showed examples describing the several different ways a
conference might be created using CCMP. This section focuses on
user-related scenarios, i.e., typical scenarios that may occur during
<span class="grey">Barnes, et al. Informational [Page 31]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-32" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
the lifetime of a conference, like adding new users and handling
their media. The following scenarios are based on those documented
in the XCON framework. The examples assume that a conference has
already been correctly established, with media, if applicable, per
one of the examples in <a href="#section-5">Section 5</a>.
<span class="h3"><a class="selflink" id="section-6.1" href="#section-6.1">6.1</a>. Adding a Party</span>
In this example, Alice wants to add Bob to an established conference.
In the following example we assume Bob is a new user of the system,
which means Alice also needs to provide some details about him. In
fact, the case of Bob already present as a user in the conferencing
system is much easier to address, and will be discussed later.
Alice Bob
CMCC1 CMCC2 CMCCx ConfS
| | | |
|(1) userRequest(confUserID,| |
| confObjID, create, | |
| userInfo) | | |
|-------------------------------------->|
| | | |
| | (a) Create +---|
| | | Bob | |
| | | as a | |
| | | user +-->|
| | | |
|(2) userResponse(confUserID, confObjID |
| create, 200, success, userInfo) |
|<--------------------------------------|
| | | |
| | | (b) Focus |
| | | sets up |
| | | signaling |
| | | to Bob |
| |<----------------------|
| | | |
| | | (c) Notify|
| | | ("Bob just|
| | | joined") |
| | |<----------|
| | | |
' ' ' '
' ' ' '
' ' ' '
Figure 11: Client Manipulation of Conference - Add a Party
<span class="grey">Barnes, et al. Informational [Page 32]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-33" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
1. Alice sends a userRequest message with an operation of "create"
to add Bob to the specific conference as identified by the XCON-
URI in the <confObjID>. The "create" <operation> also makes sure
that Bob is created as a user in the whole conferencing system.
This is done by adding in the request a <userInfo> element
describing Bob as a user. This is needed in order to let the
conferencing system be aware of Bob's characteristics. In case
Bob was already a registered user, Alice would just have
referenced him through his XCON-USERID in the 'entity' attribute
of the <userInfo> field, without providing additional data. In
fact, that data (including, for instance, Bob's SIP-URI to be
used subsequently for dial-out) would be obtained by referencing
the extant registration. The conference server ensures that
Alice has the appropriate authority based on the policies
associated with that specific conference object to perform the
operation. As mentioned before, a new XCON-USERID is created for
Bob, and the <userInfo> is used to update the conference object
accordingly. As already seen in <a href="#section-5.3">Section 5.3</a>, a placeholder
wildcard ("xcon-userid:AUTO_GENERATE_1@example.com" in the CCMP
messages below) is used for the 'entity' attribute of the
<userInfo> element, to be replaced by the actual XCON-USERID
later;
2. Bob is successfully added to the conference object, and an XCON-
USERID is allocated for him ("xcon-userid:Bob@example.com"); this
identifier is reported in the response as the value of the
'entity' attribute of the returned <userInfo>;
3. In the presented example, the call signaling to add Bob to the
conference is instigated through the focus as well. As noted
previously, this is implementation specific. In fact, a
conferencing system may accomplish different actions after the
user creation, just as it may do nothing at all. Among the
possible actions, for instance, Bob may be added as a <target>
element to the <allowed-users-list> element, whose joining
'method' may be either "dial-in" or "dial-out". Besides, out-of-
band notification mechanisms may be involved as well, e.g., to
notify Bob via mail of the new conference, including details as
the date, password, expected participants, and so on (see
<a href="#section-4.3">Section 4.3</a>).
Once Bob has been successfully added to the specified conference,
per updates to the state, and depending upon the policies, other
participants (including Bob himself) may be notified of the
addition of Bob to the conference via the conference notification
service in use.
<span class="grey">Barnes, et al. Informational [Page 33]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-34" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<span class="h2"><a class="selflink" id="section-1" href="#section-1">1</a>. userRequest/create message (Alice adds Bob)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-user-request-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8977878@example.com</confObjID>
<operation>create</operation>
<ccmp:userRequest>
<userInfo entity="xcon-userid:AUTO_GENERATE_1@example.com">
<info:display-text>Bob</info:display-text>
<info:associated-aors>
<info:entry>
<info:uri>mailto:bob.depippis@example.com</info:uri>
<info:display-text>Bob's email</info:display-text>
</info:entry>
</info:associated-aors>
<info:endpoint entity="sip:bob83@example.com">
<info:display-text>Bob's laptop</info:display-text>
</info:endpoint>
</userInfo>
</ccmp:userRequest>
</ccmpRequest>
</ccmp:ccmpRequest>
<span class="h2"><a class="selflink" id="section-2" href="#section-2">2</a>. userResponse/create message (a new XCON-USERID is</span>
<span class="h2"> created for Bob and he is added to the conference)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-user-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8977878@example.com</confObjID>
<operation>create</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<version>10</version>
<ccmp:userResponse>
<userInfo entity="xcon-userid:Bob@example.com">
<info:display-text>Bob</info:display-text>
<info:associated-aors>
<info:entry>
<span class="grey">Barnes, et al. Informational [Page 34]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-35" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<info:uri>mailto:bob.depippis@example.com</info:uri>
<info:display-text>Bob's email</info:display-text>
</info:entry>
</info:associated-aors>
<info:endpoint entity="sip:bob83@example.com">
<info:display-text>Bob's laptop</info:display-text>
</info:endpoint>
</userInfo>
</ccmp:userResponse>
</ccmpResponse>
</ccmp:ccmpResponse>
Figure 12: Add Party Message Details
<span class="h3"><a class="selflink" id="section-6.2" href="#section-6.2">6.2</a>. Muting a Party</span>
This section provides an example of the muting of a party in an
active conference. We assume that the user to mute has already been
added to the conference. The document only addresses muting and not
unmuting, since the latter would involve an almost identical CCMP
message flow anyway. However, if any external floor control is
involved, whether a particular conferencing client can actually mute/
unmute itself must be considered by the conferencing system.
Please notice that interaction between CCMP and floor control
should be carefully considered. In fact, handling CCMP- and BFCP-
based media control has to be considered as multiple layers: that
is, a participant may have the BFCP floor granted, but be muted by
means of CCMP. If so, he would still be muted in the conference,
and would only be unmuted if both the protocols allowed for this.
Figure 13 provides an example of one client, Alice, impacting the
media state of another client, Bob. This example assumes an
established conference. In this example, Alice, who is the moderator
of the conference, wants to mute Bob on a medium-sized multi-party
conference, as his device is not muted (and he's obviously not
listening to the call) and background noise in his office environment
is disruptive to the conference. BFCP floor control is assumed not
to be involved.
Muting can be accomplished using the <mute> control element
associated with the target user's audio, in which case the conference
server must update the settings associated with the user's media
streams. Muting/unmuting can also be accomplished by directly
modifying the settings related to the target user's media streams,
which is the approach shown in this example. Specifically, Bob's
<userInfo> is updated by modifying the <endpoint> element in the
<span class="grey">Barnes, et al. Informational [Page 35]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-36" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<media> part related to audio information, identified by the 'id'
attribute. The modification consists in setting the audio <status>
to "recvonly", in case of muting.
Alice Bob
CMCC1 CMCC2 CMCCx ConfS MS
| | | | |
|(1) userRequest(subject, | | |
| confUserID,confObjID, | | |
| update,userInfo) | | |
| | | | |
|--------------------------------------->| |
| | | | Mute Bob |
| | | |----------------->|
| | | | 200 OK |
| | | |<-----------------|
| | | | |
| |<====== XXX Bob excluded from mix XXX ====>|
| | | | |
| | (a) Update +---| |
| | Bob in | | |
| | data model | | |
| | (muted) +-->| |
| | | | |
| (2)userResponse(confUserID,confObjID, | |
| update,200,success,version) | |
|<---------------------------------------| |
| | | | |
| | | (b) Notify | |
| | | ("Bob is | |
| | | muted") | |
| | |<-----------| |
| | | | |
' ' ' ' '
' ' ' ' '
' ' ' ' '
Figure 13: Client Manipulation of Conference - Mute a Party
1. Alice sends a userRequest message with an "update" <operation>
and the <userInfo> with the <status> field in the <media> element
for Bob's <endpoint> set to "revconly". In order to authenticate
herself, Alice provides in the <subject> request parameter her
registration credentials (i.e., username and password). The
<subject> parameter is an optional one: its use can be systematic
whenever the conference server envisages to authenticate each
<span class="grey">Barnes, et al. Informational [Page 36]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-37" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
requester. In such cases, if the client does not provide the
required authentication information, the conferencing server
answers with a CCMP "authenticationRequired" <response-code>,
indicating that the request cannot be processed without including
the proper <subject> parameter. The conference server ensures
that Alice has the appropriate authority based on the policies
associated with that specific conference object to perform the
operation. It recognizes that Alice is allowed to request the
specified modification, since she is moderator of the target
conference, and updates the <userInfo> in the conference object
reflecting that Bob's media is not to be mixed with the
conference media. If the conference server relies on a remote
media server for its multimedia functionality, it subsequently
changes Bob's media profile accordingly by means of the related
protocol interaction with the MS. An example describing a
possible way of dealing with such a situation using the media
server control architecture [<a href="./rfc5567" title=""An Architectural Framework for Media Server Control"">RFC5567</a>] is described in Figure 31,
"Simple Bridging: Framework Transactions (2)", in [<a href="#ref-CALL-FLOWS">CALL-FLOWS</a>].
2. A userResponse message with a "200" <response-code> ("success")
is then sent to Alice. Depending upon the policies, the
conference server may notify other participants (including Bob)
of this update via any conference notification service that may
be in use.
1. userRequest/update message (Alice mutes Bob)
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-user-request-message-type">
<subject>
<username>Alice83</username>
<conference-password>13011983</conference-password>
</subject>
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8977878@example.com</confObjID>
<operation>update</operation>
<ccmp:userRequest>
<userInfo entity="xcon-userid:Bob@example.com">
<info:endpoint entity="sip:bob83@example.com">
<info:media id="1">
<info:label>123</info:label>
<info:status>recvonly</info:status>
</info:media>
</info:endpoint>
<span class="grey">Barnes, et al. Informational [Page 37]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-38" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
</userInfo>
</ccmp:userRequest>
</ccmpRequest>
</ccmp:ccmpRequest>
<span class="h2"><a class="selflink" id="section-2" href="#section-2">2</a>. userResponse/update message (Bob has been muted)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-user-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8977878@example.com</confObjID>
<operation>update</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<version>7</version>
<ccmp:userResponse/>
</ccmpResponse>
</ccmp:ccmpResponse>
Figure 14: Mute Message Details
<span class="h3"><a class="selflink" id="section-6.3" href="#section-6.3">6.3</a>. Conference Announcements and Recordings</span>
This section deals with features that are typically required in a
conferencing system, such as public announcements (e.g., to notify
vocally that a new user joined a conference) and name recording.
While this is not strictly CCMP-related (the CCMP signaling is
actually the same as the one seen in <a href="#section-6.1">Section 6.1</a>), it is an
interesting scenario to address to see how several components of an
XCON-compliant architecture interact with each other to make it
happen.
In this example, as shown in Figure 15, Alice is joining Bob's
conference that requires that she first enter a passcode. After
successfully entering the passcode, an announcement prompts Alice to
speak her name so it can be recorded. When Alice is added to the
active conference, the recording is played back to all the existing
participants. A very similar example is presented in Figure 33 of
[<a href="#ref-CALL-FLOWS">CALL-FLOWS</a>].
<span class="grey">Barnes, et al. Informational [Page 38]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-39" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
CMCC Alice ConfS MS
| | |
|(1)userRequest(confObjID, | |
| create,userInfo) | |
|--------------------------->| |
| |--+ Alice is |
| | | new in the |
| |<-+ system (create |
| | confUserID) |
| ConfS handles +--| |
| SIP signaling | | |
| (Alice<->ConfS<->MS) +->| |
| | |
| |--+ A password is |
| | | required for |
| |<-+ that conference |
| | |
| | Request IVR menu (PIN) |
| |--------------------------->|
| | |
|<========= MS gets PIN from Alice through DTMF =========>|
| | |
| | Provided PIN is... |
| |<---------------------------|
| Check +--| |
| PIN | | |
| +->| |
| |--+ Alice must |
| | | record her |
| |<-+ name |
| | |
| | Request name recording |
| |--------------------------->|
| | |
|<========= MS records Alice's audio RTP (name) =========>|
| | |
| | Audio recording |
| |<---------------------------|
| Complete +--| |
| creation | | |
| of Alice +->| |
<span class="grey">Barnes, et al. Informational [Page 39]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-40" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
| | |
| | |
| (2)userResponse(confUserID,| |
| confObjID,create,200,| |
| success,version) | |
|<---------------------------| |
| | |
' ' '
Figure 15: Recording and Announcements
1. Upon receipt of the userRequest message from Alice to be added to
Bob's conference, the conference server determines that a
password is required for this specific conference. Thus, an
announcement asking Alice to enter the password is sent back.
This may be achieved by means of typical IVR functionality. Once
Alice enters the password, it is validated against the policies
associated with Bob's active conference. The conference server
then connects to a server that prompts and records Alice's name.
The conference server must also determine whether Alice is
already a user of this conferencing system or whether she is a
new user. In this case, Alice is a new user for this
conferencing system, so a new XCON-USERID is created for Alice.
Based upon the contact information provided by Alice, the call
signaling to add Alice to the conference is instigated through
the focus.
2. The conference server sends Alice a userResponse message that
includes in the <confUserID> the XCON-USERID assigned by the
conferencing system to her. This would allow Alice to later
perform operations on the conference (if she were to have the
appropriate policies), including registering for event
notifications associated with the conference. Once the call
signaling indicates that Alice has been successfully added to the
specific conference, per updates to the state, and depending upon
the policies, other participants (e.g., Bob) are notified of the
addition of Alice to the conference via the conference
notification service and an announcement is provided to all the
participants indicating that Alice has joined the conference.
1. userRequest/create message (a new conferencing system client,
Alice, enters Bob's conference)
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<span class="grey">Barnes, et al. Informational [Page 40]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-41" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-user-request-message-type">
<confObjID>xcon:bobConf@example.com</confObjID>
<operation>create</operation>
<ccmp:userRequest>
<userInfo entity="xcon-userid:AUTO_GENERATE_1@example.com">
<info:associated-aors>
<info:entry>
<info:uri>
mailto:Alice83@example.com
</info:uri>
<info:display-text>email</info:display-text>
</info:entry>
</info:associated-aors>
<info:endpoint entity="sip:alice_789@example.com"/>
</userInfo>
</ccmp:userRequest>
</ccmpRequest>
</ccmp:ccmpRequest>
2. userResponse/create message (Alice provided with a new XCON-USERID
and added to the conference)
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-user-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:bobConf@example.com</confObjID>
<operation>create</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<version>5</version>
<ccmp:userResponse/>
</ccmpResponse>
</ccmp:ccmpResponse>
Figure 16: Announcement Messaging Details
<span class="h3"><a class="selflink" id="section-6.4" href="#section-6.4">6.4</a>. Monitoring for DTMF</span>
Conferencing systems also often need the capability to monitor for
dual-tone multi-frequency (DTMF) from each individual participant.
This would typically be used to enter the identifier and/or access
code for joining a specific conference. This feature is also often
<span class="grey">Barnes, et al. Informational [Page 41]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-42" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
exploited to achieve interaction between participants and the
conferencing system for non-XCON-aware user agents (e.g., using DTMF
tones to get muted/unmuted).
An example of DTMF monitoring, within the context of the framework
elements, is shown in Figure 15. The media control architecture and
protocols [<a href="./rfc5567" title=""An Architectural Framework for Media Server Control"">RFC5567</a>] can be used by the conference server for all the
DTMF interactions. Examples for DTMF interception in conference
instances are presented in [<a href="#ref-CALL-FLOWS">CALL-FLOWS</a>].
<span class="h3"><a class="selflink" id="section-6.5" href="#section-6.5">6.5</a>. Entering a Password-Protected Conference</span>
Some conferences may require a password to be provided by a user who
wants to manipulate the conference objects (e.g., join, update,
delete) via CCMP. In this case, a password would be included in the
<conference-password> element in the appropriate <conference-uris>
entry of the conference data model. Such password must be then
included in the <conference-password> field in the CCMP request
addressed to that conference.
In the following example, Alice, a conferencing system client,
attempts to join a password-protected conference.
1. Alice sends a userRequest message with a "create" <operation> to
add herself in the conference with XCON-URI
"xcon:8977777@example.com" (written in the <confObjID>
parameter). Alice provides her XCON-USERID via the <confUserID>
field of the userRequest message and leaves out the <userInfo>
one (first-party join). In this first attempt, she doesn't
insert any password parameter.
2. Upon receipt the userRequest/create message, the conference
server detects that the indicated conference is not joinable
without providing the appropriate passcode. A userResponse
message with a "423" <response-code> ("conference password
required") is returned to Alice to indicate that her join has
been refused and that she has to resend her request including the
appropriate conference password in order to participate.
3. After getting the passcode through out-of-band mechanisms, Alice
provides it in the proper <conference-password> request field of
a new userRequest/create message and sends the updated request
back to the server.
4. The conference server checks the provided password and then adds
Alice to the protected conference. After that, a userResponse
message with a "200" <response-code> ("success") is sent to
Alice.
<span class="grey">Barnes, et al. Informational [Page 42]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-43" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
1. userRequest/create message (Alice tries to enter the conference
without providing the password)
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-user-request-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8977794@example.com</confObjID>
<operation>create</operation>
<ccmp:userRequest/>
</ccmpRequest>
</ccmp:ccmpRequest>
2. userResponse/create message ("423", "conference password required")
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-user-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8977794@example.com</confObjID>
<operation>create</operation>
<response-code>423</response-code>
<response-string>conference password required</response-string>
<ccmp:userResponse/>
</ccmpResponse>
</ccmp:ccmpResponse>
3. userRequest/create message (Alice provides the password)
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-user-request-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8977794@example.com</confObjID>
<operation>create</operation>
<conference-password>8601</conference-password>
<span class="grey">Barnes, et al. Informational [Page 43]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-44" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<ccmp:userRequest/>
</ccmpRequest>
</ccmp:ccmpRequest>
4. userResponse/create message
(Alice has been added to the conference)
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-user-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8977794@example.com</confObjID>
<operation>create</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<version>10</version>
<ccmp:userResponse/>
</ccmpResponse>
</ccmp:ccmpResponse>
Figure 17: Password-Protected Conference Join Messages Details
<span class="h2"><a class="selflink" id="section-7" href="#section-7">7</a>. Sidebars Scenarios and Examples</span>
While creating conferences and manipulating users and their media are
sufficient for many scenarios, there may be cases when more complex
management is needed.
In fact, a feature typically required in conferencing systems is the
ability to create sidebars. A sidebar is basically a child
conference that usually includes a subset of the participants of the
parent conference and a subset of its media as well. Sidebars are
typically required whenever some of the participants in a conference
want a private discussion, without interfering with the main
conference.
This section deals with some typical scenarios using a sidebar, like
whispering, private messaging, and coaching scenarios. The first
subsections present some examples of how a generic sidebar can be
created, configured, and managed.
<span class="grey">Barnes, et al. Informational [Page 44]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-45" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<span class="h3"><a class="selflink" id="section-7.1" href="#section-7.1">7.1</a>. Internal Sidebar</span>
Figure 18 provides an example of one client, Alice, involved in an
active conference with Bob and Carol. Alice wants to create a
sidebar to have a side discussion with Bob while still viewing the
video associated with the main conference. Alternatively, the audio
from the main conference could be maintained at a reduced volume.
Alice initiates the sidebar by sending a request to the ConfS to
create a conference reservation based upon the active conference
object. Alice and Bob would remain on the roster of the main
conference, such that other participants could be aware of their
participation in the main conference, while an internal-sidebar
conference is occurring. Besides, Bob decides that he is not
interested in still receiving the conference audio in background (not
even at a lower volume as Alice configured) and so modifies the
sidebar in order to make that stream inactive for him.
Alice Bob ConfS
| | |
|(1) sidebarByValRequest(confUserID, |
| confObjID,create) |
|--------------------------------------------->|
| | |
| | (a) Create +---|
| | sidebar-by-val | |
| | (new conf obj | |
| | cloned from +-->|
| | confObjID) | Sidebar now has
| | | id confObjID*
|(2) sidebarByValResponse(confUserID, | (parent mapping
| (confObjID*,create,200,success, | conf<->sidebar)
| version,sidebarByValInfo) |
|<---------------------------------------------|
| | |
|(3) sidebarByValRequest |
| (confUserID, confObjID*, |
| update,sidebarByValInfo) |
|--------------------------------------------->|
| | |
<span class="grey">Barnes, et al. Informational [Page 45]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-46" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
| | (b) Update +---|
| | sidebar-by-val | |
| | (media, users | |
| | etc.) +-->|
| | | Sidebar is
| | | modified
|(4) sidebarByValResponse(confUserID, |
| confObjID*, update, |
| 200, success, version) |
|<---------------------------------------------|
| | |
| |(5) userRequest |
| | (confUserID', |
| | confObjID*, |
| | update,userInfo)|
| |---------------------->|
| | |
| | (c) Update +---|
| | user settings | |
| | (Bob's media) | |
| | +-->|
| | | Sidebar is modified
| | | (original audio
| | | inactive for Bob)
| |(6) userResponse |
| | (confUserID', |
| | confObjID*, |
| | update, 200, |
| | success,version) |
| |<----------------------|
| | |
' ' '
' ' '
' ' '
Figure 18: Client Creation of a Sidebar Conference
1. Upon receipt of CCMP sidebarByValRequest message to create a new
sidebar based upon the conference whose XCON-URI is in the
<confObjID> received in the request, the conference server uses
such XCON-URI to clone a conference reservation for the sidebar.
The sidebar reservation is NOT independent of the active main
conference (i.e., parent). The conference server also allocates
a new XCON-URI ("confObjID*" in Figure 18) for that sidebar to be
used for any subsequent protocol requests from any of the members
of the conference. The new XCON-URI is returned in the response
message <confObjID> parameter.
<span class="grey">Barnes, et al. Informational [Page 46]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-47" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
2. The relationship information is provided in the
sidebarByValResponse message, specifically in the <sidebar-
parent> element. A dump of the complete representation of the
main/parent conference is provided below as well to show how the
cloning process for the creation of the sidebar could take place.
3. Upon receipt of the sidebarByValResponse message to reserve the
conference, Alice can now create an active conference using that
reservation or create additional reservations based upon the
existing reservations. In this example, Alice wants only Bob to
be involved in the sidebar; thus, she manipulates the membership
so that only the two of them appear in the <allowed-users-list>
section. Alice also wants both audio and video from the original
conference to be available in the sidebar. For what concerns the
media belonging to the sidebar itself, Alice wants the audio to
be restricted to the participants in the sidebar (that is, Bob
and herself). Additionally, Alice manipulates the media values
to receive the audio from the main conference at a reduced
volume, so that the communication between her and Bob isn't
affected. Alice sends a sidebarByValRequest message with an
operation of "update" along with the <sidebarByValInfo>
containing the aforementioned sidebar modifications.
4. Upon receipt of the sidebarByValRequest message to update the
sidebar reservation, the conference server ensures that Alice has
the appropriate authority based on the policies associated with
that specific conference object to perform the operation. The
conference server must also validate the updated information in
the reservation, ensuring that a member like Bob is already a
user of this conference server. Once the data for the conference
identified by the <confObjID> is updated, the conference server
sends a sidebarByValResponse message to Alice. Depending upon
the policies, the initiator of the request (i.e., Alice) and the
participants in the sidebar (i.e., Bob) may be notified of his
addition to the sidebar via the conference notification service.
5. At this point, Bob sends a userRequest message to the conference
server with an operation of "update" to completely disable the
background audio from the parent conference, since it prevents
him from understanding what Alice says in the sidebar.
6. Notice that Bob's request only changes the media perspective for
Bob. Alice keeps on receiving both the audio from Bob and the
background from the parent conference. This request may be
relayed by the conference server to the media server handling the
mixing, if present. Upon completion of the change, the
<span class="grey">Barnes, et al. Informational [Page 47]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-48" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
conference server sends a userResponse message to Bob. Depending
upon the policies, the initiator of the request (i.e., Bob) and
the participants in the sidebar (i.e., Alice) may be notified of
this change via the conference notification service.
The following conference object represents the conference in which
the sidebar is to be created. It will be used by the conference
server to create the new conference object associated with the
sidebar.
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<info:conference-info
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
entity="xcon:8977878@example.com">
<info:conference-description>
<info:display-text>MAIN CONFERENCE</info:display-text>
<info:conf-uris>
<info:entry>
<info:uri>sip:8977878@example.com</info:uri>
<info:display-text>conference sip uri</info:display-text>
</info:entry>
</info:conf-uris>
<info:available-media>
<info:entry label="123">
<info:display-text>main conference audio</info:display-text>
<info:type>audio</info:type>
<info:status>sendrecv</info:status>
</info:entry>
<info:entry label="456">
<info:display-text>main conference video</info:display-text>
<info:type>video</info:type>
<info:status>sendrecv</info:status>
<xcon:controls>
<xcon:video-layout>single-view</xcon:video-layout>
</xcon:controls>
</info:entry>
</info:available-media>
</info:conference-description>
<info:conference-state>
<info:active>true</info:active>
</info:conference-state>
<info:users>
<info:user entity="xcon-userid:Alice@example.com">
<info:display-text>Alice</info:display-text>
<info:endpoint entity="sip:Alice@example.com">
<info:media id="1">
<span class="grey">Barnes, et al. Informational [Page 48]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-49" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<info:label>123</info:label>
<info:status>sendrecv</info:status>
</info:media>
<info:media id="2">
<info:label>456</info:label>
<info:status>sendrecv</info:status>
</info:media>
</info:endpoint>
</info:user>
<info:user entity="xcon-userid:Bob@example.com">
<info:display-text>Bob</info:display-text>
<info:endpoint entity="sip:bob83@example.com">
<info:media id="1">
<info:label>123</info:label>
<info:status>sendrecv</info:status>
</info:media>
<info:media id="2">
<info:label>456</info:label>
<info:status>sendrecv</info:status>
</info:media>
</info:endpoint>
</info:user>
<info:user entity="xcon-userid:Carol@example.com">
<info:display-text>Carol</info:display-text>
<info:endpoint entity="sip:carol@example.com">
<info:media id="1">
<info:label>123</info:label>
<info:status>sendrecv</info:status>
</info:media>
<info:media id="2">
<info:label>456</info:label>
<info:status>sendrecv</info:status>
</info:media>
</info:endpoint>
</info:user>
</info:users>
</info:conference-info>
Figure 19: Conference with Alice, Bob, and Carol
The sidebar creation happens through a cloning of the parent
conference. Once the sidebar is created, an update request makes
sure that the sidebar is customized as needed. The following
protocol dump makes the process clearer.
<span class="grey">Barnes, et al. Informational [Page 49]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-50" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<span class="h2"><a class="selflink" id="section-1" href="#section-1">1</a>. sidebarByValRequest/create message (Alice creates an</span>
<span class="h2"> internal sidebar)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-sidebarByVal-request-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8977878@example.com</confObjID>
<operation>create</operation>
<ccmp:sidebarByValRequest/>
</ccmpRequest>
</ccmp:ccmpRequest>
<span class="h2"><a class="selflink" id="section-2" href="#section-2">2</a>. sidebarByValResponse/create message (sidebar returned)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-sidebarByVal-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8974545@example.com</confObjID>
<operation>create</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<version>1</version>
<ccmp:sidebarByValResponse>
<sidebarByValInfo entity="xcon:8974545@example.com">
<info:conference-description>
<info:display-text>
SIDEBAR CONFERENCE registered by Alice
</info:display-text>
<info:available-media>
<info:entry label="123">
<info:display-text>
main conference audio
</info:display-text>
<info:type>audio</info:type>
<info:status>sendrecv</info:status>
</info:entry>
<info:entry label="456">
<info:display-text>
main conference video
<span class="grey">Barnes, et al. Informational [Page 50]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-51" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
</info:display-text>
<info:type>video</info:type>
<info:status>sendrecv</info:status>
</info:entry>
</info:available-media>
</info:conference-description>
<info:conference-state>
<info:active>false</info:active>
</info:conference-state>
<info:users>
<xcon:allowed-users-list>
<xcon:target method="dial-in"
uri="xcon-userid:Alice@example.com"/>
<xcon:target method="dial-in"
uri="xcon-userid:Bob@example.com"/>
<xcon:target method="dial-in"
uri="xcon-userid:Carol@example.com"/>
</xcon:allowed-users-list>
<xcon:sidebar-parent>
xcon:8977878@example.com
</xcon:sidebar-parent>
</info:users>
</sidebarByValInfo>
</ccmp:sidebarByValResponse>
</ccmpResponse>
</ccmp:ccmpResponse>
<span class="h2"><a class="selflink" id="section-3" href="#section-3">3</a>. sidebarByValRequest/update message (Alice updates the</span>
<span class="h2"> created sidebar)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-sidebarByVal-request-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8974545@example.com</confObjID>
<operation>update</operation>
<ccmp:sidebarByValRequest>
<sidebarByValInfo entity="xcon:8974545@example.com">
<info:conference-description>
<info:display-text>
private sidebar Alice - Bob
</info:display-text>
<info:available-media>
<info:entry label="123">
<span class="grey">Barnes, et al. Informational [Page 51]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-52" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<info:display-text>
main conference audio
</info:display-text>
<info:type>audio</info:type>
<info:status>recvonly</info:status>
<xcon:controls>
<xcon:gain>-60</xcon:gain>
</xcon:controls>
</info:entry>
<info:entry label="456">
<info:display-text>
main conference video
</info:display-text>
<info:type>video</info:type>
<info:status>recvonly</info:status>
</info:entry>
<info:entry label="AUTO_GENERATE_1">
<info:display-text>
sidebar audio
</info:display-text>
<info:type>audio</info:type>
<info:status>sendrecv</info:status>
</info:entry>
<info:entry label="AUTO_GENERATE_2">
<info:display-text>
sidebar video
</info:display-text>
<info:type>video</info:type>
<info:status>sendrecv</info:status>
</info:entry>
</info:available-media>
</info:conference-description>
<info:users>
<xcon:allowed-users-list>
<xcon:target method="dial-out"
uri="xcon-userid:Alice@example.com"/>
<xcon:target method="dial-out"
uri="xcon-userid:Bob@example.com"/>
</xcon:allowed-users-list>
</info:users>
</sidebarByValInfo>
</ccmp:sidebarByValRequest>
</ccmpRequest>
</ccmp:ccmpRequest>
<span class="grey">Barnes, et al. Informational [Page 52]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-53" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<span class="h2"><a class="selflink" id="section-4" href="#section-4">4</a>. sidebarByValResponse/update message (sidebar's</span>
<span class="h2"> updates accepted)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-sidebarByVal-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8974545@example.com</confObjID>
<operation>update</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<version>2</version>
<ccmp:sidebarByValResponse/>
</ccmpResponse>
</ccmp:ccmpResponse>
<span class="h2"><a class="selflink" id="section-5" href="#section-5">5</a>. userRequest/update message (Bob updates his media)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-user-request-message-type">
<confUserID>xcon-userid:Bob@example.com</confUserID>
<confObjID>xcon:8974545@example.com</confObjID>
<operation>update</operation>
<ccmp:userRequest>
<userInfo entity="xcon-userid:Bob@example.com">
<info:endpoint entity="sip:bob83@example.com">
<info:media id="1">
<info:display-text>
main conference audio
</info:display-text>
<info:label>123</info:label>
<info:status>inactive</info:status>
</info:media>
</info:endpoint>
</userInfo>
</ccmp:userRequest>
</ccmpRequest>
</ccmp:ccmpRequest>
<span class="grey">Barnes, et al. Informational [Page 53]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-54" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<span class="h2"><a class="selflink" id="section-6" href="#section-6">6</a>. userResponse/update message (Bob's preferences are set)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-user-response-message-type">
<confUserID>xcon-userid:Bob@example.com</confUserID>
<confObjID>xcon:8974545@example.com</confObjID>
<operation>update</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<version>3</version>
<ccmp:userResponse/>
</ccmpResponse>
</ccmp:ccmpResponse>
Figure 20: Internal Sidebar Messaging Details
<span class="h3"><a class="selflink" id="section-7.2" href="#section-7.2">7.2</a>. External Sidebar</span>
Figure 21 provides an example of a different approach towards
sidebars. In this scenario, one client, Alice, is involved in an
active conference with Bob, Carol, David, and Ethel. Alice gets an
important text message via a whisper from Bob that a critical
customer needs to talk to Alice, Bob, and Ethel. Alice creates a
sidebar to have a side discussion with the customer Fred including
the participants in the current conference with the exception of
Carol and David, who remain in the active conference. The difference
from the previous scenario is that Fred is not part of the parent
conference: this means that different policies might be involved,
considering that Fred may access information coming from the parent
conference, in case the sidebar was configured accordingly. For this
reason, in this scenario, we assume that Alice disables all the media
from the original (parent) conference within the sidebar. This means
that, while in the previous example Alice and Bob still heard the
audio from the main conference in background, this time no background
is made available. Alice initiates the sidebar by sending a request
to the conference server to create a conference reservation based
upon the active conference object. Alice, Bob and Ethel would remain
on the roster of the main conference in a hold state. Whether or not
the hold state of these participants is visible to other participants
depends upon the individual and local policy. However, providing the
hold state allows the participants in the main conference to see that
others in the conference are busy. Note, that a separate conference
could have been created by Alice to allow Bob and Ethel to talk to
Fred. However, creating a sidebar has somewhat of an advantage by
<span class="grey">Barnes, et al. Informational [Page 54]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-55" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
allowing the conference to be created using some of the same settings
(e.g., role, floor control, etc.) that Bob and Ethel had in the main
conference and it would allow for updates such that the media could
be updated, for example, to provide audio from the main conference.
Alice Bob ConfS
| | |
|(1) sidebarByRefRequest(confUserID, |
| confObjID, create) |
|--------------------------------------------->|
| | |
| | (a) Create +---|
| | sidebar-by-ref | |
| | (new conf obj | |
| | cloned from +-->|
| | confObjID) | Sidebar now has
| | | id confObjID*
|(2) sidebarByRefResponse(confUserID, | (parent mapping
| confObjID*,create,200,success, | conf<->sidebar)
| version,sidebarByRefInfo) |
|<---------------------------------------------|
| | |
|(3) sidebarByRefRequest(confUserID, |
| confObjID*,update,sidebarByRefInfo) |
|--------------------------------------------->|
| | |
| | (b) Create +---|
| | new user for | |
| | Fred | |
| | +-->|
| | |
| | (c) Update +---|
| | sidebar-by-ref | |
| | (media, users | |
| | policy, etc.) +-->|
| | | Sidebar is modified:
| | | media from the
| | | parent conference is
| | | not available to
|(4) sidebarByRefResponse(confUserID, | anyone
| confObjID*, update, |
| 200, success, version) |
|<---------------------------------------------|
| | |
<span class="grey">Barnes, et al. Informational [Page 55]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-56" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
| | Notify (Fred |
| | added to |
| | sidebar users) |
| |<----------------------|
| | |
' ' '
' ' '
' ' '
Figure 21: Client Creation of an External Sidebar
1. Upon receipt of the sidebarByRefRequest message to create a new
sidebar conference, based upon the active conference specified by
<confObjID> in the request, the conference server uses that
active conference to clone a conference reservation for the
sidebar. The sidebar reservation is NOT independent of the
active conference (i.e., parent). The conference server, as
before, allocates a new XCON-URI ("confObjID*" in Figure 21) to
be used for any subsequent protocol requests toward the sidebar
reservation. The mapping between the sidebar XCON-URI and the
one associated with the main conference is maintained by the
conference server and it is gathered from the <sidebar-parent>
element in the sidebar conference object.
2. Upon receipt of the sidebarByRefResponse message, which
acknowledges the successful creation of the sidebar object, Alice
decides that only Bob and Ethel, along with the new participant
Fred are to be involved in the sidebar. Thus, she manipulates
the membership accordingly. Alice also sets the media in the
<conference-info> such that the participants in the sidebar don't
receive any media from the main conference. All these settings
are provided to the conferencing server by means of a new
sidebarByRefRequest message, with an "update" <operation>.
3. Alice sends the aforementioned sidebarByRefRequest message to
update the information in the reservation and to create an active
conference. Upon receipt of the sidebarByRefRequest/update
message, the conference server ensures that Alice has the
appropriate authority based on the policies associated with that
specific conference object to perform the operation. The
conference server also validates the updated information in the
reservation. Since Fred is a new user for this conferencing
system, a conference user identifier (XCON-USERID) is created for
Fred. Specifically, Fred is added to the conference by only
providing his SIP URI. Based upon the contact information
provided for Fred by Alice, the call signaling to add Fred to the
conference may be instigated through the focus (e.g., if Fred had
<span class="grey">Barnes, et al. Informational [Page 56]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-57" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
a "dial-out" value for the 'method' attribute in his <target>
field under <allowed-users-list>) at the actual activation of the
sidebar.
4. The conference server sends a sidebarByRefResponse message and,
depending upon the policies, the initiator of the request (i.e.,
Alice) and the participants in the sidebar (i.e., Bob and Ethel)
may be notified of his addition to the sidebar via the conference
notification service.
<span class="h2"><a class="selflink" id="section-1" href="#section-1">1</a>. sidebarByRefRequest/create message (Alice creates an</span>
<span class="h2"> external sidebar)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-sidebarByRef-request-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8977878@example.com</confObjID>
<operation>create</operation>
<ccmp:sidebarByRefRequest/>
</ccmpRequest>
</ccmp:ccmpRequest>
<span class="h2"><a class="selflink" id="section-2" href="#section-2">2</a>. sidebarByRefResponse/create message (created</span>
<span class="h2"> sidebar returned)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-sidebarByRef-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8971212@example.com</confObjID>
<operation>create</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<version>1</version>
<ccmp:sidebarByRefResponse>
<sidebarByRefInfo entity="xcon:8971212@example.com">
<info:conference-description>
<info:display-text>
SIDEBAR CONFERENCE registered by Alice
</info:display-text>
<span class="grey">Barnes, et al. Informational [Page 57]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-58" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<info:available-media>
<info:entry label="123">
<info:display-text>
main conference audio
</info:display-text>
<info:type>audio</info:type>
<info:status>sendrecv</info:status>
</info:entry>
<info:entry label="456">
<info:display-text>
main conference video
</info:display-text>
<info:type>video</info:type>
<info:status>sendrecv</info:status>
</info:entry>
</info:available-media>
</info:conference-description>
<info:conference-state>
<info:active>false</info:active>
</info:conference-state>
<info:users>
<xcon:allowed-users-list>
<xcon:target method="dial-in"
uri="xcon-userid:Alice@example.com"/>
<xcon:target method="dial-in"
uri="xcon-userid:Bob@example.com"/>
<xcon:target method="dial-in"
uri="xcon-userid:Carol@example.com"/>
<xcon:target method="dial-in"
uri="xcon-userid:David@example.com"/>
<xcon:target method="dial-in"
uri="xcon-userid:Ethel@example.com"/>
</xcon:allowed-users-list>
<xcon:sidebar-parent>
xcon:8977878@example.com
</xcon:sidebar-parent>
</info:users>
</sidebarByRefInfo>
</ccmp:sidebarByRefResponse>
</ccmpResponse>
</ccmp:ccmpResponse>
<span class="h2"><a class="selflink" id="section-3" href="#section-3">3</a>. sidebarByRefRequest/update message (Alice updates the sidebar)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
<span class="grey">Barnes, et al. Informational [Page 58]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-59" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-sidebarByRef-request-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8971212@example.com</confObjID>
<operation>update</operation>
<ccmp:sidebarByRefRequest>
<sidebarByRefInfo entity="xcon:8971212@example.com">
<info:conference-description>
<info:display-text>
sidebar with Alice, Bob, Ethel and Fred
</info:display-text>
<info:available-media>
<info:entry label="123">
<info:display-text>
main conference audio
</info:display-text>
<info:type>audio</info:type>
<info:status>inactive</info:status>
</info:entry>
<info:entry label="456">
<info:display-text>
main conference video
</info:display-text>
<info:type>video</info:type>
<info:status>inactive</info:status>
</info:entry>
<info:entry label="AUTO_GENERATE_1">
<info:display-text>
sidebar audio
</info:display-text>
<info:type>audio</info:type>
<info:status>sendrecv</info:status>
</info:entry>
<info:entry label="AUTO_GENERATE_2">
<info:display-text>
sidebar video
</info:display-text>
<info:type>video</info:type>
<info:status>sendrecv</info:status>
<xcon:controls>
<xcon:video-layout>
single-view
</xcon:video-layout>
</xcon:controls>
</info:entry>
</info:available-media>
</info:conference-description>
<span class="grey">Barnes, et al. Informational [Page 59]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-60" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<info:conference-state>
<info:active>false</info:active>
</info:conference-state>
<info:users>
<xcon:allowed-users-list>
<xcon:target method="dial-out"
uri="xcon-userid:Alice@example.com"/>
<xcon:target method="dial-out"
uri="xcon-userid:Bob@example.com"/>
<xcon:target method="dial-out"
uri="sip:fred@example.com"/>
</xcon:allowed-users-list>
</info:users>
</sidebarByRefInfo>
</ccmp:sidebarByRefRequest>
</ccmpRequest>
</ccmp:ccmpRequest>
<span class="h2"><a class="selflink" id="section-4" href="#section-4">4</a>. sidebarByRefResponse/update message (sidebar updated)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-sidebarByRef-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8971212@example.com</confObjID>
<operation>update</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<version>2</version>
<ccmp:sidebarByRefResponse/>
</ccmpResponse>
</ccmp:ccmpResponse>
Figure 22: External Sidebar Messaging Details
<span class="h3"><a class="selflink" id="section-7.3" href="#section-7.3">7.3</a>. Private Messages</span>
The case of private messages can be handled as a sidebar with just
two participants, similar to the example in <a href="#section-7.1">Section 7.1</a>. Unlike the
previous example, rather than using audio within the sidebar, Alice
could just add an additional text-based media stream to the sidebar
in order to convey her textual messages to Bob, while still viewing
and listening to the main conference.
<span class="grey">Barnes, et al. Informational [Page 60]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-61" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
In this scenario, Alice requests to the conference server the
creation of a private chat room within the main conference context
(presented in Figure 19) in which the involved participants are just
Bob and herself. This can be achieved through the following CCMP
transaction (Figure 23).
1. Alice forwards a sidebarByValRequest/create message to the
conference server with the main conference XCON-URI in the
<confObjID> parameter and the desired sidebar conference object
in the <sidebarByValInfo> field. In this way, a sidebar creation
using user-provided conference information is requested from the
conference server. Please note that, unlike the previous sidebar
examples, in this case, a completely new conference object to
describe the sidebar is provided: there is no cloning involved,
while the <confObjID> still enforces the parent-child
relationship between the main conference and the to-be-created
sidebar.
2. The conference server, after checking Alice's rights and
validating the conference object carried in the request, creates
the required sidebar-by-val conference and a new XCON-URI for it.
Instead of cloning the main conference object, as shown in
Sections <a href="#section-7.1">7.1</a> and <a href="#section-7.2">7.2</a>, the sidebar is created on the basis of the
user-provided conference information. However, the parent
relationship between the main conference and the newly created
sidebar is still maintained by the conference server (as a
consequence of the chosen CCMP request message type -- the
sidebarByVal one) and it is reflected by the <sidebar-parent>
element in the <sidebarByValInfo> element returned in the
sidebarByValResponse message. Please notice that, according to
the CCMP specification, the return of the created sidebar data in
this kind of "success" response is not mandatory.
<span class="h2"><a class="selflink" id="section-1" href="#section-1">1</a>. sidebarByValRequest/create message (Alice creates a private</span>
<span class="h2"> chat room between Bob and herself)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-sidebarByVal-request-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8977878@example.com</confObjID>
<operation>create</operation>
<ccmp:sidebarByValRequest>
<sidebarByValInfo entity="xcon:AUTO_GENERATE_1@example.com">
<span class="grey">Barnes, et al. Informational [Page 61]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-62" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<info:conference-description>
<info:display-text>
private textual sidebar alice - bob
</info:display-text>
<info:available-media>
<info:entry label="123">
<info:display-text>
main conference audio
</info:display-text>
<info:type>audio</info:type>
<info:status>recvonly</info:status>
</info:entry>
<info:entry label="456">
<info:display-text>
main conference video
</info:display-text>
<info:type>video</info:type>
<info:status>recvonly</info:status>
</info:entry>
<info:entry label="AUTO_GENERATE_2">
<info:display-text>
sidebar text
</info:display-text>
<info:type>text</info:type>
<info:status>sendrecv</info:status>
</info:entry>
</info:available-media>
</info:conference-description>
<info:users>
<xcon:allowed-users-list>
<xcon:target method="dial-out"
uri="xcon-userid:Alice@example.com"/>
<xcon:target method="dial-out"
uri="xcon-userid:Bob@example.com"/>
</xcon:allowed-users-list>
</info:users>
</sidebarByValInfo>
</ccmp:sidebarByValRequest>
</ccmpRequest>
</ccmp:ccmpRequest>
<span class="h2"><a class="selflink" id="section-2" href="#section-2">2</a>. sidebarByValResponse/create message (sidebar returned)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<span class="grey">Barnes, et al. Informational [Page 62]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-63" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-sidebarByVal-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8974545@example.com</confObjID>
<operation>create</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<version>1</version>
<ccmp:sidebarByValResponse>
<sidebarByValInfo entity="xcon:8974545@example.com">
<info:conference-description>
<info:display-text>
private textual sidebar alice - bob
</info:display-text>
<info:available-media>
<info:entry label="123">
<info:display-text>
main conference audio
</info:display-text>
<info:type>audio</info:type>
<info:status>recvonly</info:status>
</info:entry>
<info:entry label="456">
<info:display-text>
main conference video
</info:display-text>
<info:type>video</info:type>
<info:status>recvonly</info:status>
</info:entry>
<info:entry label="789">
<info:display-text>
sidebar text
</info:display-text>
<info:type>text</info:type>
<info:status>sendrecv</info:status>
</info:entry>
</info:available-media>
<xcon:sidebar-parent>
xcon:8977878@example.com
</xcon:sidebar-parent>
</info:conference-description>
<info:users>
<xcon:allowed-users-list>
<xcon:target method="dial-out"
uri="xcon-userid:Alice@example.com"/>
<xcon:target method="dial-out"
uri="xcon-userid:Bob@example.com"/>
</xcon:allowed-users-list>
<span class="grey">Barnes, et al. Informational [Page 63]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-64" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
</info:users>
</sidebarByValInfo>
</ccmp:sidebarByValResponse>
</ccmpResponse>
</ccmp:ccmpResponse>
Figure 23: Sidebar for Private Messages Scenario
<span class="h3"><a class="selflink" id="section-7.4" href="#section-7.4">7.4</a>. Observing and Coaching</span>
"Observing and Coaching" is one of the most interesting sidebar-
related scenarios. In fact, it highlights two different interactions
that have to be properly coordinated.
An example of observing and coaching is shown in Figure 25. In this
example, call center agent Bob is involved in a conference with
customer Carol. Since Bob is a new agent and Alice sees that he has
been on the call with Carol for longer than normal, she decides to
observe the call and coach Bob as necessary. Of course, the
conferencing system must make sure that the customer Carol is not
aware of the presence of the coach Alice. This makes the use of a
sidebar necessary for the success of the scenario.
Consider the following as the conference document associated with the
video conference involving Bob (the call agent) and Carol (the
customer) (Figure 24):
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<info:conference-info
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
entity="xcon:8978383@example.com">
<info:conference-description>
<info:display-text>
CUSTOMER SERVICE conference
</info:display-text>
<info:conf-uris>
<info:entry>
<info:uri>sip:8978383@example.com</info:uri>
<info:display-text>conference sip uri</info:display-text>
</info:entry>
</info:conf-uris>
<info:available-media>
<info:entry label="123">
<info:display-text>service audio</info:display-text>
<info:type>audio</info:type>
<info:status>sendrecv</info:status>
<span class="grey">Barnes, et al. Informational [Page 64]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-65" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
</info:entry>
<info:entry label="456">
<info:display-text>service video</info:display-text>
<info:type>video</info:type>
<info:status>sendrecv</info:status>
<xcon:controls>
<xcon:video-layout>single-view</xcon:video-layout>
</xcon:controls>
</info:entry>
</info:available-media>
</info:conference-description>
<info:conference-state>
<info:active>true</info:active>
</info:conference-state>
<info:users>
<info:user entity="xcon-userid:bob@example.com">
<info:display-text>Bob - call agent</info:display-text>
<info:endpoint entity="sip:bob@example.com">
<info:media id="1">
<info:label>123</info:label>
<info:status>sendrecv</info:status>
</info:media>
<info:media id="2">
<info:label>456</info:label>
<info:status>sendrecv</info:status>
</info:media>
</info:endpoint>
</info:user>
<info:user entity="xcon-userid:carol@example.com">
<info:display-text>Carol - customer</info:display-text>
<info:endpoint entity="sip:carol@example.com">
<info:media id="1">
<info:label>123</info:label>
<info:status>sendrecv</info:status>
</info:media>
<info:media id="2">
<info:label>456</info:label>
<info:status>sendrecv</info:status>
</info:media>
</info:endpoint>
</info:user>
</info:users>
</info:conference-info>
Figure 24: A Call-Center Conference Object Example
<span class="grey">Barnes, et al. Informational [Page 65]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-66" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
Alice Bob ConfS
| | |
|(1) sidebarByRefRequest(confUserID, |
| confObjID, create) |
|--------------------------------------------->|
| | |
| | (a) Create +---|
| | sidebar-by-ref | |
| | (new conf obj | |
| | cloned from +-->|
| | confObjID) | Sidebar now has
| | | id confObjID*
|(2) sidebarByRefResponse(confUserID, | (parent mapping
| confObjID*,create,200,success, | conf<->sidebar)
| version,sidebarByRefInfo) |
|<---------------------------------------------|
| | |
|(3) sidebarByRefRequest(confUserID, |
| confObjID*,update,sidebarByRefInfo) |
|--------------------------------------------->|
| | |
| | (b) Update +---|
| | sidebar-by-val | |
| | (media, users | |
| | policy, etc.) +-->|
| | | Sidebar is modified:
| | | unilateral sidebar
| | | audio, Carol excluded
| | | from the sidebar
|(4) sidebarByRefResponse(confUserID, |
| confObjID*, update, |
| 200, success, version) |
|<---------------------------------------------|
| | |
| | Notify (Bob |
| | he's been added to |
| | sidebar users) |
| |<----------------------|
| | |
' ' '
' ' '
' ' '
Figure 25: Supervisor Creating a Sidebar for Observing/Coaching
<span class="grey">Barnes, et al. Informational [Page 66]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-67" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
1. Upon receipt of the sidbarByRefRequest/create message from Alice
to create a new sidebar conference from the <confObjID> received
in the request, the conference server uses the received active
conference to clone a conference reservation for the sidebar.
The conference server also allocates a new XCON-URI to be used
for any subsequent protocol requests directed to the new sidebar.
The conference server maintains the mapping between this sidebar
conference ID and the one associated with the main conference
instance. The conference server sends a sidebarByRefResponse
message with the new XCON-URI in the <confObjID> field and other
relevant information in the <sidebarByRefInfo>.
2. Upon receipt of the sidebarByRefResponse message, Alice
manipulates the data received in the <sidebarByRefInfo> in the
response. Alice wants only Bob to be involved in the sidebar;
thus, she updates the <allowed-users-list> to include only Bob
and herself. Alice also wants the audio to be received by
herself and Bob from the original conference, but wants any
outgoing audio from herself to be restricted to the participants
in the sidebar, whereas Bob's outgoing audio should go to the
main conference, so that both Alice and the customer Carol hear
the same audio from Bob. Alice sends a sidebarByRefRequest
message with an "update" <operation> including the updated
sidebar information in the <sidebarByRefInfo> element.
3. Upon receipt of the sidebarByRefRequest/update message, the
conference server ensures that Alice has the appropriate
authority based on the policies associated with that specific
conference object to perform the operation. In order to request
the insertion of a further media stream in the sidebar (i.e., in
this example an audio stream from Alice to Bob), the requester
has to provide a new <entry> element in the <available-media>
field of the <sidebarByRefInfo>. The mandatory 'label' attribute
of that new <entry> is filled with a dummy value
"AUTO_GENERATE_1", but it will contain the real server-generated
media stream identifier when the media stream is effectively
allocated on the server side. Similarly, the mandatory 'id'
attribute in the <media> element referring to the new sidebar
audio stream under both Alice's and Bob's <endpoint> contains a
wildcard value, respectively, "AUTO_GENERATE_2" and
"AUTO_GENERATE_3": those values will be replaced with the
appropriated server-generated identifiers upon the creation of
the referred media stream. We are assuming the conference server
is able to recognize those dummy values as placeholders.
4. After validating the data, the conference server sends a
sidebarByRefResponse message. Based upon the contact information
provided for Bob by Alice, the call signaling to add Bob to the
<span class="grey">Barnes, et al. Informational [Page 67]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-68" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
sidebar with the appropriate media characteristics is instigated
through the focus. Bob is notified of his addition to the
sidebar via the conference notification service; thus, he is
aware that Alice, the supervisor, is available for coaching him
through this call.
<span class="h2"><a class="selflink" id="section-1" href="#section-1">1</a>. sidebarByRefRequest/create message (Alice as coach creates a sidebar)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-sidebarByRef-request-message-type">
<confUserID>xcon-userid:alice@example.com</confUserID>
<confObjID>xcon:8978383@example.com</confObjID>
<operation>create</operation>
<ccmp:sidebarByRefRequest/>
</ccmpRequest>
</ccmp:ccmpRequest>
<span class="h2"><a class="selflink" id="section-2" href="#section-2">2</a>. sidebarByRefResponse/create message (sidebar created)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-sidebarByRef-response-message-type">
<confUserID>xcon-userid:alice@example.com</confUserID>
<confObjID>xcon:8971313@example.com</confObjID>
<operation>create</operation>
<response-code>200</response-code>
<response-string>Success</response-string>
<version>1</version>
<ccmp:sidebarByRefResponse>
<sidebarByRefInfo entity="xcon:8971313@example.com">
<info:conference-description>
<info:display-text>
SIDEBAR CONFERENCE registered by alice
</info:display-text>
<info:available-media>
<info:entry label="123">
<info:display-text>
main conference audio
</info:display-text>
<info:type>audio</info:type>
<span class="grey">Barnes, et al. Informational [Page 68]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-69" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<info:status>sendrecv</info:status>
</info:entry>
<info:entry label="456">
<info:display-text>
main conference video
</info:display-text>
<info:type>video</info:type>
<info:status>sendrecv</info:status>
</info:entry>
</info:available-media>
<xcon:sidebar-parent>
xcon:8971313@example.com
</xcon:sidebar-parent>
</info:conference-description>
<info:conference-state>
<info:active>false</info:active>
</info:conference-state>
<info:users>
<xcon:allowed-users-list>
<xcon:target method="dial-in"
uri="xcon-userid:alice@example.com"/>
<xcon:target method="dial-in"
uri="xcon-userid:bob@example.com"/>
<xcon:target method="dial-in"
uri="xcon-userid:carol@example.com"/>
</xcon:allowed-users-list>
</info:users>
</sidebarByRefInfo>
</ccmp:sidebarByRefResponse>
</ccmpResponse>
</ccmp:ccmpResponse>
3. sidebarByRefRequest/update message (Alice introduces unilateral
sidebar audio and excludes Carol from the sidebar)
<ccmp:ccmpRequest
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-sidebarByRef-request-message-type">
<confUserID>xcon-userid:alice@example.com</confUserID>
<confObjID>xcon:8971313@example.com</confObjID>
<operation>update</operation>
<ccmp:sidebarByRefRequest>
<sidebarByRefInfo entity="xcon:8971313@example.com">
<span class="grey">Barnes, et al. Informational [Page 69]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-70" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<info:conference-description>
<info:display-text>
Coaching sidebar Alice and Bob
</info:display-text>
<info:available-media>
<info:entry label="AUTO_GENERATE_1">
<info:display-text>
Alice-to-Bob audio
</info:display-text>
<info:type>audio</info:type>
<info:status>sendrecv</info:status>
</info:entry>
</info:available-media>
</info:conference-description>
<info:conference-state>
<info:active>false</info:active>
</info:conference-state>
<info:users>
<info:user entity="xcon-userid:alice@example.com">
<info:endpoint entity="sip:alice@example.com">
<info:media id="AUTO_GENERATE_2">
<info:label>AUTO_GENERATE_1</info:label>
<info:status>sendonly</info:status>
</info:media>
</info:endpoint>
</info:user>
<info:user entity="xcon-userid:bob@example.com">
<info:endpoint entity="sip:bob@example.com">
<info:media id="AUTO_GENERATE_3">
<info:label>AUTO_GENERATE_1</info:label>
<info:status>recvonly</info:status>
</info:media>
</info:endpoint>
</info:user>
<xcon:allowed-users-list>
<xcon:target method="dial-in"
uri="xcon-userid:alice@example.com"/>
<xcon:target method="dial-out"
uri="xcon-userid:bob@example.com"/>
</xcon:allowed-users-list>
</info:users>
</sidebarByRefInfo>
</ccmp:sidebarByRefRequest>
</ccmpRequest>
</ccmp:ccmpRequest>
<span class="grey">Barnes, et al. Informational [Page 70]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-71" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<span class="h2"><a class="selflink" id="section-4" href="#section-4">4</a>. sidebarByRefRequest/update message (updates accepted)</span>
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info"
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp">
<ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-sidebarByRef-response-message-type">
<confUserID>xcon-userid:alice@example.com</confUserID>
<confObjID>xcon:8971313@example.com</confObjID>
<operation>update</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<version>2</version>
<ccmp:sidebarByRefResponse/>
</ccmpResponse>
</ccmp:ccmpResponse>
Figure 26: Coaching and Observing Messaging Details
<span class="h2"><a class="selflink" id="section-8" href="#section-8">8</a>. Removing Participants and Deleting Conferences</span>
The following scenarios detail the basic operations associated with
removing participants from conferences and entirely deleting
conferences. The examples assume that a conference has already been
correctly established, with media, if applicable, per one of the
examples in <a href="#section-5">Section 5</a>.
<span class="h3"><a class="selflink" id="section-8.1" href="#section-8.1">8.1</a>. Removing a Party</span>
Figure 27 provides an example of a client, Alice, removing another
participant, Bob, from a conference. This example assumes an
established conference with Alice, Bob, Claire, and Duck. In this
example, Alice wants to remove Bob from the conference so that the
group can continue in the same conference without Bob's
participation.
<span class="grey">Barnes, et al. Informational [Page 71]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-72" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
Alice Bob Claire ConfS
| | | |
|(1) userRequest(confUserID,| |
| confObjID, delete,| |
| userInfo) | |
|-------------------------------------->|
| | | |
| | | (a) Focus |
| | | tears down|
| | | signaling |
| | | to Bob |
| |<----------------------|
| | |
| | (b)Deletes+---|
| | | Bob | |
| | | as a | |
| | | user +-->|
| | | in |
| | | confObj |
| | | |
|(2) userResponse(confUserID,confObjID, |
| delete,200,success,version) |
|<--------------------------------------|
| | | |
| | | |
| | | (c) Notify|
| | | ("Bob just|
| | | left") |
| | |<----------|
| | | |
' ' ' '
' ' ' '
' ' ' '
Figure 27: Client Manipulation of Conference - Remove a Party
1. Alice sends a userRequest message with a "delete" <operation>.
The conference server ensures that Alice has the appropriate
authority based on the policies associated with that specific
conference object to perform the operation.
2. Based upon the contact and media information in the conference
object for Bob in the <userInfo> element, the conferencing system
starts the process to remove Bob (e.g., the call signaling to
remove Bob from the conference is instigated through the focus).
The conference server updates the data in the conference object,
thus, removing Bob from the <users> list. After updating the
data, the conference server sends a userResponse message to
<span class="grey">Barnes, et al. Informational [Page 72]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-73" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
Alice. Depending upon the policies, other participants (e.g.,
Claire) may be notified of the removal of Bob from the conference
via the conference notification service.
1. userRequest/delete message (Alice deletes Bob)
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-user-request-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8977794@example.com</confObjID>
<operation>delete</operation>
<ccmp:userRequest>
<userInfo entity="xcon-userid:Bob@example.com"/>
</ccmp:userRequest>
</ccmpRequest>
</ccmp:ccmpRequest>
2. userResponse/delete message (Bob has been deleted)
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-user-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8977794@example.com</confObjID>
<operation>delete</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<version>17</version>
<ccmp:userResponse/>
</ccmpResponse>
</ccmp:ccmpResponse>
Figure 28: Removing a Participant Messaging Details
<span class="grey">Barnes, et al. Informational [Page 73]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-74" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<span class="h3"><a class="selflink" id="section-8.2" href="#section-8.2">8.2</a>. Deleting a Conference</span>
In this section, an example of a successful conference deletion is
provided (Figure 29).
Alice ConfS
| |
|(1)confRequest(confUserID, |
| confObjID, delete) |
|------------------------------>|
| (a)Delete +---|
| Conf | |
| Object | |
| +-->|
| |--+ (b) MS
| | | removes related
| | | mixer instances and
| |<-+ their participants
| | (SIP signaling as well)
| |
|(2)confResponse(confUserID, |
| confObjID,delete,200, |
| success) |
| |
|<------------------------------|
| |
' '
Figure 29: Deleting a Conference
1. The conferencing system client Alice sends a confRequest message
with a "delete" operation to be performed on the conference
identified by the XCON-URI carried in the <confObjID> parameter.
The conference server, on the basis of the <confUserID> included
in the receipt request, ensures that Alice has the appropriate
authority to fulfill the operation.
2. After validating Alice's rights, the conference server instigates
the process to delete the conference object, disconnecting
participants and removing associated resources such as mixer
instances. Then, the conference server returns a confResponse
message to Alice with "200" as <response-code> and the deleted
conference XCON-URI in the <confObjID> field.
<span class="grey">Barnes, et al. Informational [Page 74]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-75" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
1. confRequest/delete message (Alice deletes a conference)
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpRequest
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-conf-request-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8977794@example.com</confObjID>
<operation>delete</operation>
<ccmp:confRequest/>
</ccmpRequest>
</ccmp:ccmpRequest>
2. confResponse/delete message ("200", "success")
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ccmp:ccmpResponse
xmlns:info="urn:ietf:params:xml:ns:conference-info"
xmlns:ccmp="urn:ietf:params:xml:ns:xcon:ccmp"
xmlns:xcon="urn:ietf:params:xml:ns:xcon-conference-info">
<ccmpResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:type="ccmp:ccmp-conf-response-message-type">
<confUserID>xcon-userid:Alice@example.com</confUserID>
<confObjID>xcon:8977794@example.com</confObjID>
<operation>delete</operation>
<response-code>200</response-code>
<response-string>success</response-string>
<ccmp:confResponse/>
</ccmpResponse>
</ccmp:ccmpResponse>
Figure 30: Deleting a Conference Messaging Details
<span class="h2"><a class="selflink" id="section-9" href="#section-9">9</a>. Security Considerations</span>
The security considerations applicable to the implementation of these
call flows are documented in the XCON framework, with additional
security considerations documented in the CCMP document. Statements
with regard to the necessary security are discussed in particular
flows; however, this is for informational purposes only. The
implementer is encouraged to carefully consider the security
requirements in the normative documents.
<span class="grey">Barnes, et al. Informational [Page 75]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-76" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
<span class="h2"><a class="selflink" id="section-10" href="#section-10">10</a>. Acknowledgements</span>
The detailed content for this document is derived from the prototype
work of Lorenzo Miniero, Simon Pietro Romano, Tobia Castaldi, and
their colleagues at the University of Napoli.
<span class="h2"><a class="selflink" id="section-11" href="#section-11">11</a>. References</span>
<span class="h3"><a class="selflink" id="section-11.1" href="#section-11.1">11.1</a>. Normative References</span>
[<a id="ref-RFC5239">RFC5239</a>] Barnes, M., Boulton, C., and O. Levin, "A Framework for
Centralized Conferencing", <a href="./rfc5239">RFC 5239</a>, June 2008.
[<a id="ref-RFC6501">RFC6501</a>] Novo, O., Camarillo, G., Morgan, D., and J. Urpalainen,
"Conference Information Data Model for Centralized
Conferencing (XCON)", <a href="./rfc6501">RFC 6501</a>, March 2012.
[<a id="ref-RFC6502">RFC6502</a>] Camarillo, G., Srinivasan, S., Even, R., and J.
Urpalainen, "Conference Event Package Data Format
Extension for Centralized Conferencing (XCON)", <a href="./rfc6502">RFC 6502</a>,
March 2012.
[<a id="ref-RFC6503">RFC6503</a>] Barnes, M., Boulton, C., Romano, S., and H. Schulzrinne,
"Centralized Conferencing Manipulation Protocol",
<a href="./rfc6503">RFC 6503</a>, March 2012.
[<a id="ref-W3C.REC-xml-20081126">W3C.REC-xml-20081126</a>]
Bray, T., Paoli, J., Sperberg-McQueen, C., Maler, E., and
F. Yergeau, "Extensible Markup Language (XML) 1.0 (Fifth
Edition)", World Wide Web Consortium Recommendation REC-
xml-20081126, November 2008,
<<a href="http://www.w3.org/TR/2008/REC-xml-20081126">http://www.w3.org/TR/2008/REC-xml-20081126</a>>.
<span class="h3"><a class="selflink" id="section-11.2" href="#section-11.2">11.2</a>. Informative References</span>
[<a id="ref-CALL-FLOWS">CALL-FLOWS</a>]
Amirante, A., Castaldi, T., Miniero, L., and S. Romano,
"Media Control Channel Framework (CFW) Call Flow
Examples", Work in Progress, July 2011.
[<a id="ref-RFC3261">RFC3261</a>] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston,
A., Peterson, J., Sparks, R., Handley, M., and E.
Schooler, "SIP: Session Initiation Protocol", <a href="./rfc3261">RFC 3261</a>,
June 2002.
[<a id="ref-RFC4575">RFC4575</a>] Rosenberg, J., Schulzrinne, H., and O. Levin, "A Session
Initiation Protocol (SIP) Event Package for Conference
State", <a href="./rfc4575">RFC 4575</a>, August 2006.
<span class="grey">Barnes, et al. Informational [Page 76]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-77" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
[<a id="ref-RFC4579">RFC4579</a>] Johnston, A. and O. Levin, "Session Initiation Protocol
(SIP) Call Control - Conferencing for User Agents",
<a href="https://www.rfc-editor.org/bcp/bcp119">BCP 119</a>, <a href="./rfc4579">RFC 4579</a>, August 2006.
[<a id="ref-RFC4582">RFC4582</a>] Camarillo, G., Ott, J., and K. Drage, "The Binary Floor
Control Protocol (BFCP)", <a href="./rfc4582">RFC 4582</a>, November 2006.
[<a id="ref-RFC4597">RFC4597</a>] Even, R. and N. Ismail, "Conferencing Scenarios",
<a href="./rfc4597">RFC 4597</a>, August 2006.
[<a id="ref-RFC5567">RFC5567</a>] Melanchuk, T., "An Architectural Framework for Media
Server Control", <a href="./rfc5567">RFC 5567</a>, June 2009.
[<a id="ref-RFC6505">RFC6505</a>] McGlashan, S., Melanchuk, T., and C. Boulton, "A Mixer
Control Package for the Media Control Channel Framework",
<a href="./rfc6505">RFC 6505</a>, March 2012.
<span class="grey">Barnes, et al. Informational [Page 77]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-78" ></span>
<span class="grey"><a href="./rfc6504">RFC 6504</a> CCMP Call Flow Examples March 2012</span>
Authors' Addresses
Mary Barnes
Polycom
TX
USA
EMail: mary.ietf.barnes@gmail.com
Lorenzo Miniero
Meetecho
Via Carlo Poerio 89/a
Napoli 80121
Italy
EMail: lorenzo@meetecho.com
Roberta Presta
University of Napoli
Via Claudio 21
Napoli 80125
Italy
EMail: roberta.presta@unina.it
Simon Pietro Romano
University of Napoli
Via Claudio 21
Napoli 80125
Italy
EMail: spromano@unina.it
Barnes, et al. Informational [Page 78]
</pre>
|