File: rfc9004.html

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<!DOCTYPE html>
<html lang="en" class="RFC">
<head>
<meta charset="utf-8">
<meta content="Common,Latin" name="scripts">
<meta content="initial-scale=1.0" name="viewport">
<title>RFC 9004: Updates for the Back-to-Back Frame Benchmark in RFC 2544</title>
<meta content="Al Morton" name="author">
<meta content="
       Fundamental benchmarking methodologies for network interconnect
      devices of interest to the IETF are defined in RFC 2544. This memo
      updates the procedures of the test to measure the Back-to-Back Frames
      benchmark of RFC 2544, based on further experience. 
       This memo updates Section 26.4 of RFC 2544. 
    " name="description">
<meta content="xml2rfc 3.8.0" name="generator">
<meta content="Buffer size" name="keyword">
<meta content="Buffer delay" name="keyword">
<meta content="Correction Factor" name="keyword">
<meta content="9004" name="rfc.number">
<!-- Generator version information:
  xml2rfc 3.8.0
    Python 3.6.10
    appdirs 1.4.4
    ConfigArgParse 1.2.3
    google-i18n-address 2.3.5
    html5lib 1.0.1
    intervaltree 3.0.2
    Jinja2 2.11.2
    kitchen 1.2.6
    lxml 4.4.2
    pycairo 1.19.0
    pycountry 19.8.18
    pyflakes 2.1.1
    PyYAML 5.3.1
    requests 2.22.0
    setuptools 40.6.2
    six 1.14.0
    WeasyPrint 51
-->
<link href="rfc9004.xml" rel="alternate" type="application/rfc+xml">
<link href="#copyright" rel="license">
<style type="text/css">/*

  NOTE: Changes at the bottom of this file overrides some earlier settings.

  Once the style has stabilized and has been adopted as an official RFC style,
  this can be consolidated so that style settings occur only in one place, but
  for now the contents of this file consists first of the initial CSS work as
  provided to the RFC Formatter (xml2rfc) work, followed by itemized and
  commented changes found necssary during the development of the v3
  formatters.

*/

/* fonts */
@import url('https://fonts.googleapis.com/css?family=Noto+Sans'); /* Sans-serif */
@import url('https://fonts.googleapis.com/css?family=Noto+Serif'); /* Serif (print) */
@import url('https://fonts.googleapis.com/css?family=Roboto+Mono'); /* Monospace */

@viewport {
  zoom: 1.0;
  width: extend-to-zoom;
}
@-ms-viewport {
  width: extend-to-zoom;
  zoom: 1.0;
}
/* general and mobile first */
html {
}
body {
  max-width: 90%;
  margin: 1.5em auto;
  color: #222;
  background-color: #fff;
  font-size: 14px;
  font-family: 'Noto Sans', Arial, Helvetica, sans-serif;
  line-height: 1.6;
  scroll-behavior: smooth;
}
.ears {
  display: none;
}

/* headings */
#title, h1, h2, h3, h4, h5, h6 {
  margin: 1em 0 0.5em;
  font-weight: bold;
  line-height: 1.3;
}
#title {
  clear: both;
  border-bottom: 1px solid #ddd;
  margin: 0 0 0.5em 0;
  padding: 1em 0 0.5em;
}
.author {
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}
h1 {
  font-size: 26px;
  margin: 1em 0;
}
h2 {
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h3 {
  font-size: 18px;
  margin-top: -36px;  /* provide offset for in-page anchors */
  padding-top: 42px;
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h4 {
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  margin-top: -36px;  /* provide offset for in-page anchors */
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h5, h6 {
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}
#n-copyright-notice {
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  padding-bottom: 1em;
  margin-bottom: 1em;
}
/* general structure */
p {
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  margin: 0 0 1em 0;
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}
div, span {
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}
div {
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}
.alignRight.art-text {
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  padding: 1em 1em 0;
  margin-bottom: 1.5em;
}
.alignRight.art-text pre {
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}
.alignRight {
  margin: 1em 0;
}
.alignRight > *:first-child {
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  float: right;
  clear: both;
}
.alignRight > *:nth-child(2) {
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  display: block;
  border: none;
}
svg {
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}
.alignCenter.art-text {
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}
.alignCenter.art-text pre {
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}
.alignCenter {
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}
.alignCenter > *:first-child {
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     support flexbox yet.
  */
  display: table;
  margin: 0 auto;
}

/* lists */
ol, ul {
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  margin: 0 0 1em 2em;
}
ol ol, ul ul, ol ul, ul ol {
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}
li {
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}
.ulCompact li {
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}
ul.empty, .ulEmpty {
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}
ul.empty li, .ulEmpty li {
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}
ul.compact, .ulCompact,
ol.compact, .olCompact {
  line-height: 100%;
  margin: 0 0 0 2em;
}

/* definition lists */
dl {
}
dl > dt {
  float: left;
  margin-right: 1em;
}
/* 
dl.nohang > dt {
  float: none;
}
*/
dl > dd {
  margin-bottom: .8em;
  min-height: 1.3em;
}
dl.compact > dd, .dlCompact > dd {
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}
dl > dd > dl {
  margin-top: 0.5em;
  margin-bottom: 0em;
}

/* links */
a {
  text-decoration: none;
}
a[href] {
  color: #22e; /* Arlen: WCAG 2019 */
}
a[href]:hover {
  background-color: #f2f2f2;
}
figcaption a[href],
a[href].selfRef {
  color: #222;
}
/* XXX probably not this:
a.selfRef:hover {
  background-color: transparent;
  cursor: default;
} */

/* Figures */
tt, code, pre, code {
  background-color: #f9f9f9;
  font-family: 'Roboto Mono', monospace;
}
pre {
  border: 1px solid #eee;
  margin: 0;
  padding: 1em;
}
img {
  max-width: 100%;
}
figure {
  margin: 0;
}
figure blockquote {
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}
figcaption {
  font-style: italic;
  margin: 0 0 1em 0;
}
@media screen {
  pre {
    overflow-x: auto;
    max-width: 100%;
    max-width: calc(100% - 22px);
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}

/* aside, blockquote */
aside, blockquote {
  margin-left: 0;
  padding: 1.2em 2em;
}
blockquote {
  background-color: #f9f9f9;
  color: #111; /* Arlen: WCAG 2019 */
  border: 1px solid #ddd;
  border-radius: 3px;
  margin: 1em 0;
}
cite {
  display: block;
  text-align: right;
  font-style: italic;
}

/* tables */
table {
  width: 100%;
  margin: 0 0 1em;
  border-collapse: collapse;
  border: 1px solid #eee;
}
th, td {
  text-align: left;
  vertical-align: top;
  padding: 0.5em 0.75em;
}
th {
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}
tr:nth-child(2n+1) > td {
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}
table caption {
  font-style: italic;
  margin: 0;
  padding: 0;
  text-align: left;
}
table p {
  /* XXX to avoid bottom margin on table row signifiers. If paragraphs should
     be allowed within tables more generally, it would be far better to select on a class. */
  margin: 0;
}

/* pilcrow */
a.pilcrow {
  color: #666; /* Arlen: AHDJ 2019 */
  text-decoration: none;
  visibility: hidden;
  user-select: none;
  -ms-user-select: none;
  -o-user-select:none;
  -moz-user-select: none;
  -khtml-user-select: none;
  -webkit-user-select: none;
  -webkit-touch-callout: none;
}
@media screen {
  aside:hover > a.pilcrow,
  p:hover > a.pilcrow,
  blockquote:hover > a.pilcrow,
  div:hover > a.pilcrow,
  li:hover > a.pilcrow,
  pre:hover > a.pilcrow {
    visibility: visible;
  }
  a.pilcrow:hover {
    background-color: transparent;
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}

/* misc */
hr {
  border: 0;
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}
.bcp14 {
  font-variant: small-caps;
}

.role {
  font-variant: all-small-caps;
}

/* info block */
#identifiers {
  margin: 0;
  font-size: 0.9em;
}
#identifiers dt {
  width: 3em;
  clear: left;
}
#identifiers dd {
  float: left;
  margin-bottom: 0;
}
#identifiers .authors .author {
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}
#identifiers .authors .org {
  font-style: italic;
}

/* The prepared/rendered info at the very bottom of the page */
.docInfo {
  color: #666; /* Arlen: WCAG 2019 */
  font-size: 0.9em;
  font-style: italic;
  margin-top: 2em;
}
.docInfo .prepared {
  float: left;
}
.docInfo .prepared {
  float: right;
}

/* table of contents */
#toc  {
  padding: 0.75em 0 2em 0;
  margin-bottom: 1em;
}
nav.toc ul {
  margin: 0 0.5em 0 0;
  padding: 0;
  list-style: none;
}
nav.toc li {
  line-height: 1.3em;
  margin: 0.75em 0;
  padding-left: 1.2em;
  text-indent: -1.2em;
}
/* references */
.references dt {
  text-align: right;
  font-weight: bold;
  min-width: 7em;
}
.references dd {
  margin-left: 8em;
  overflow: auto;
}

.refInstance {
  margin-bottom: 1.25em;
}

.references .ascii {
  margin-bottom: 0.25em;
}

/* index */
.index ul {
  margin: 0 0 0 1em;
  padding: 0;
  list-style: none;
}
.index ul ul {
  margin: 0;
}
.index li {
  margin: 0;
  text-indent: -2em;
  padding-left: 2em;
  padding-bottom: 5px;
}
.indexIndex {
  margin: 0.5em 0 1em;
}
.index a {
  font-weight: 700;
}
/* make the index two-column on all but the smallest screens */
@media (min-width: 600px) {
  .index ul {
    -moz-column-count: 2;
    -moz-column-gap: 20px;
  }
  .index ul ul {
    -moz-column-count: 1;
    -moz-column-gap: 0;
  }
}

/* authors */
address.vcard {
  font-style: normal;
  margin: 1em 0;
}

address.vcard .nameRole {
  font-weight: 700;
  margin-left: 0;
}
address.vcard .label {
  font-family: "Noto Sans",Arial,Helvetica,sans-serif;
  margin: 0.5em 0;
}
address.vcard .type {
  display: none;
}
.alternative-contact {
  margin: 1.5em 0 1em;
}
hr.addr {
  border-top: 1px dashed;
  margin: 0;
  color: #ddd;
  max-width: calc(100% - 16px);
}

/* temporary notes */
.rfcEditorRemove::before {
  position: absolute;
  top: 0.2em;
  right: 0.2em;
  padding: 0.2em;
  content: "The RFC Editor will remove this note";
  color: #9e2a00; /* Arlen: WCAG 2019 */
  background-color: #ffd; /* Arlen: WCAG 2019 */
}
.rfcEditorRemove {
  position: relative;
  padding-top: 1.8em;
  background-color: #ffd; /* Arlen: WCAG 2019 */
  border-radius: 3px;
}
.cref {
  background-color: #ffd; /* Arlen: WCAG 2019 */
  padding: 2px 4px;
}
.crefSource {
  font-style: italic;
}
/* alternative layout for smaller screens */
@media screen and (max-width: 1023px) {
  body {
    padding-top: 2em;
  }
  #title {
    padding: 1em 0;
  }
  h1 {
    font-size: 24px;
  }
  h2 {
    font-size: 20px;
    margin-top: -18px;  /* provide offset for in-page anchors */
    padding-top: 38px;
  }
  #identifiers dd {
    max-width: 60%;
  }
  #toc {
    position: fixed;
    z-index: 2;
    top: 0;
    right: 0;
    padding: 0;
    margin: 0;
    background-color: inherit;
    border-bottom: 1px solid #ccc;
  }
  #toc h2 {
    margin: -1px 0 0 0;
    padding: 4px 0 4px 6px;
    padding-right: 1em;
    min-width: 190px;
    font-size: 1.1em;
    text-align: right;
    background-color: #444;
    color: white;
    cursor: pointer;
  }
  #toc h2::before { /* css hamburger */
    float: right;
    position: relative;
    width: 1em;
    height: 1px;
    left: -164px;
    margin: 6px 0 0 0;
    background: white none repeat scroll 0 0;
    box-shadow: 0 4px 0 0 white, 0 8px 0 0 white;
    content: "";
  }
  #toc nav {
    display: none;
    padding: 0.5em 1em 1em;
    overflow: auto;
    height: calc(100vh - 48px);
    border-left: 1px solid #ddd;
  }
}

/* alternative layout for wide screens */
@media screen and (min-width: 1024px) {
  body {
    max-width: 724px;
    margin: 42px auto;
    padding-left: 1.5em;
    padding-right: 29em;
  }
  #toc {
    position: fixed;
    top: 42px;
    right: 42px;
    width: 25%;
    margin: 0;
    padding: 0 1em;
    z-index: 1;
  }
  #toc h2 {
    border-top: none;
    border-bottom: 1px solid #ddd;
    font-size: 1em;
    font-weight: normal;
    margin: 0;
    padding: 0.25em 1em 1em 0;
  }
  #toc nav {
    display: block;
    height: calc(90vh - 84px);
    bottom: 0;
    padding: 0.5em 0 0;
    overflow: auto;
  }
  img { /* future proofing */
    max-width: 100%;
    height: auto;
  }
}

/* pagination */
@media print {
  body {

    width: 100%;
  }
  p {
    orphans: 3;
    widows: 3;
  }
  #n-copyright-notice {
    border-bottom: none;
  }
  #toc, #n-introduction {
    page-break-before: always;
  }
  #toc {
    border-top: none;
    padding-top: 0;
  }
  figure, pre {
    page-break-inside: avoid;
  }
  figure {
    overflow: scroll;
  }
  h1, h2, h3, h4, h5, h6 {
    page-break-after: avoid;
  }
  h2+*, h3+*, h4+*, h5+*, h6+* {
    page-break-before: avoid;
  }
  pre {
    white-space: pre-wrap;
    word-wrap: break-word;
    font-size: 10pt;
  }
  table {
    border: 1px solid #ddd;
  }
  td {
    border-top: 1px solid #ddd;
  }
}

/* This is commented out here, as the string-set: doesn't
   pass W3C validation currently */
/*
.ears thead .left {
  string-set: ears-top-left content();
}

.ears thead .center {
  string-set: ears-top-center content();
}

.ears thead .right {
  string-set: ears-top-right content();
}

.ears tfoot .left {
  string-set: ears-bottom-left content();
}

.ears tfoot .center {
  string-set: ears-bottom-center content();
}

.ears tfoot .right {
  string-set: ears-bottom-right content();
}
*/

@page :first {
  padding-top: 0;
  @top-left {
    content: normal;
    border: none;
  }
  @top-center {
    content: normal;
    border: none;
  }
  @top-right {
    content: normal;
    border: none;
  }
}

@page {
  size: A4;
  margin-bottom: 45mm;
  padding-top: 20px;
  /* The follwing is commented out here, but set appropriately by in code, as
     the content depends on the document */
  /*
  @top-left {
    content: 'Internet-Draft';
    vertical-align: bottom;
    border-bottom: solid 1px #ccc;
  }
  @top-left {
    content: string(ears-top-left);
    vertical-align: bottom;
    border-bottom: solid 1px #ccc;
  }
  @top-center {
    content: string(ears-top-center);
    vertical-align: bottom;
    border-bottom: solid 1px #ccc;
  }
  @top-right {
    content: string(ears-top-right);
    vertical-align: bottom;
    border-bottom: solid 1px #ccc;
  }
  @bottom-left {
    content: string(ears-bottom-left);
    vertical-align: top;
    border-top: solid 1px #ccc;
  }
  @bottom-center {
    content: string(ears-bottom-center);
    vertical-align: top;
    border-top: solid 1px #ccc;
  }
  @bottom-right {
      content: '[Page ' counter(page) ']';
      vertical-align: top;
      border-top: solid 1px #ccc;
  }
  */

}

/* Changes introduced to fix issues found during implementation */
/* Make sure links are clickable even if overlapped by following H* */
a {
  z-index: 2;
}
/* Separate body from document info even without intervening H1 */
section {
  clear: both;
}


/* Top align author divs, to avoid names without organization dropping level with org names */
.author {
  vertical-align: top;
}

/* Leave room in document info to show Internet-Draft on one line */
#identifiers dt {
  width: 8em;
}

/* Don't waste quite as much whitespace between label and value in doc info */
#identifiers dd {
  margin-left: 1em;
}

/* Give floating toc a background color (needed when it's a div inside section */
#toc {
  background-color: white;
}

/* Make the collapsed ToC header render white on gray also when it's a link */
@media screen and (max-width: 1023px) {
  #toc h2 a,
  #toc h2 a:link,
  #toc h2 a:focus,
  #toc h2 a:hover,
  #toc a.toplink,
  #toc a.toplink:hover {
    color: white;
    background-color: #444;
    text-decoration: none;
  }
}

/* Give the bottom of the ToC some whitespace */
@media screen and (min-width: 1024px) {
  #toc {
    padding: 0 0 1em 1em;
  }
}

/* Style section numbers with more space between number and title */
.section-number {
  padding-right: 0.5em;
}

/* prevent monospace from becoming overly large */
tt, code, pre, code {
  font-size: 95%;
}

/* Fix the height/width aspect for ascii art*/
pre.sourcecode,
.art-text pre {
  line-height: 1.12;
}


/* Add styling for a link in the ToC that points to the top of the document */
a.toplink {
  float: right;
  margin-right: 0.5em;
}

/* Fix the dl styling to match the RFC 7992 attributes */
dl > dt,
dl.dlParallel > dt {
  float: left;
  margin-right: 1em;
}
dl.dlNewline > dt {
  float: none;
}

/* Provide styling for table cell text alignment */
table td.text-left,
table th.text-left {
  text-align: left;
}
table td.text-center,
table th.text-center {
  text-align: center;
}
table td.text-right,
table th.text-right {
  text-align: right;
}

/* Make the alternative author contact informatio look less like just another
   author, and group it closer with the primary author contact information */
.alternative-contact {
  margin: 0.5em 0 0.25em 0;
}
address .non-ascii {
  margin: 0 0 0 2em;
}

/* With it being possible to set tables with alignment
  left, center, and right, { width: 100%; } does not make sense */
table {
  width: auto;
}

/* Avoid reference text that sits in a block with very wide left margin,
   because of a long floating dt label.*/
.references dd {
  overflow: visible;
}

/* Control caption placement */
caption {
  caption-side: bottom;
}

/* Limit the width of the author address vcard, so names in right-to-left
   script don't end up on the other side of the page. */

address.vcard {
  max-width: 30em;
  margin-right: auto;
}

/* For address alignment dependent on LTR or RTL scripts */
address div.left {
  text-align: left;
}
address div.right {
  text-align: right;
}

/* Provide table alignment support.  We can't use the alignX classes above
   since they do unwanted things with caption and other styling. */
table.right {
 margin-left: auto;
 margin-right: 0;
}
table.center {
 margin-left: auto;
 margin-right: auto;
}
table.left {
 margin-left: 0;
 margin-right: auto;
}

/* Give the table caption label the same styling as the figcaption */
caption a[href] {
  color: #222;
}

@media print {
  .toplink {
    display: none;
  }

  /* avoid overwriting the top border line with the ToC header */
  #toc {
    padding-top: 1px;
  }

  /* Avoid page breaks inside dl and author address entries */
  .vcard {
    page-break-inside: avoid;
  }

}
/* Tweak the bcp14 keyword presentation */
.bcp14 {
  font-variant: small-caps;
  font-weight: bold;
  font-size: 0.9em;
}
/* Tweak the invisible space above H* in order not to overlay links in text above */
 h2 {
  margin-top: -18px;  /* provide offset for in-page anchors */
  padding-top: 31px;
 }
 h3 {
  margin-top: -18px;  /* provide offset for in-page anchors */
  padding-top: 24px;
 }
 h4 {
  margin-top: -18px;  /* provide offset for in-page anchors */
  padding-top: 24px;
 }
/* Float artwork pilcrow to the right */
@media screen {
  .artwork a.pilcrow {
    display: block;
    line-height: 0.7;
    margin-top: 0.15em;
  }
}
/* Make pilcrows on dd visible */
@media screen {
  dd:hover > a.pilcrow {
    visibility: visible;
  }
}
/* Make the placement of figcaption match that of a table's caption
   by removing the figure's added bottom margin */
.alignLeft.art-text,
.alignCenter.art-text,
.alignRight.art-text {
   margin-bottom: 0;
}
.alignLeft,
.alignCenter,
.alignRight {
  margin: 1em 0 0 0;
}
/* In print, the pilcrow won't show on hover, so prevent it from taking up space,
   possibly even requiring a new line */
@media print {
  a.pilcrow {
    display: none;
  }
}
/* Styling for the external metadata */
div#external-metadata {
  background-color: #eee;
  padding: 0.5em;
  margin-bottom: 0.5em;
  display: none;
}
div#internal-metadata {
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<table class="ears">
<thead><tr>
<td class="left">RFC 9004</td>
<td class="center">B2B Frame Update</td>
<td class="right">May 2021</td>
</tr></thead>
<tfoot><tr>
<td class="left">Morton</td>
<td class="center">Informational</td>
<td class="right">[Page]</td>
</tr></tfoot>
</table>
<div id="external-metadata" class="document-information"></div>
<div id="internal-metadata" class="document-information">
<dl id="identifiers">
<dt class="label-stream">Stream:</dt>
<dd class="stream">Internet Engineering Task Force (IETF)</dd>
<dt class="label-rfc">RFC:</dt>
<dd class="rfc"><a href="https://www.rfc-editor.org/rfc/rfc9004" class="eref">9004</a></dd>
<dt class="label-updates">Updates:</dt>
<dd class="updates">
<a href="https://www.rfc-editor.org/rfc/rfc2544" class="eref">2544</a> </dd>
<dt class="label-category">Category:</dt>
<dd class="category">Informational</dd>
<dt class="label-published">Published:</dt>
<dd class="published">
<time datetime="2021-05" class="published">May 2021</time>
    </dd>
<dt class="label-issn">ISSN:</dt>
<dd class="issn">2070-1721</dd>
<dt class="label-authors">Author:</dt>
<dd class="authors">
<div class="author">
      <div class="author-name">A. Morton</div>
<div class="org">AT&amp;T Labs</div>
</div>
</dd>
</dl>
</div>
<h1 id="rfcnum">RFC 9004</h1>
<h1 id="title">Updates for the Back-to-Back Frame Benchmark in RFC 2544</h1>
<section id="section-abstract">
      <h2 id="abstract"><a href="#abstract" class="selfRef">Abstract</a></h2>
<p id="section-abstract-1">Fundamental benchmarking methodologies for network interconnect
      devices of interest to the IETF are defined in RFC 2544. This memo
      updates the procedures of the test to measure the Back-to-Back Frames
      benchmark of RFC 2544, based on further experience.<a href="#section-abstract-1" class="pilcrow">¶</a></p>
<p id="section-abstract-2">This memo updates Section 26.4 of RFC 2544.<a href="#section-abstract-2" class="pilcrow">¶</a></p>
</section>
<div id="status-of-memo">
<section id="section-boilerplate.1">
        <h2 id="name-status-of-this-memo">
<a href="#name-status-of-this-memo" class="section-name selfRef">Status of This Memo</a>
        </h2>
<p id="section-boilerplate.1-1">
            This document is not an Internet Standards Track specification; it is
            published for informational purposes.<a href="#section-boilerplate.1-1" class="pilcrow">¶</a></p>
<p id="section-boilerplate.1-2">
            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 candidates for any level of Internet
            Standard; see Section 2 of RFC 7841.<a href="#section-boilerplate.1-2" class="pilcrow">¶</a></p>
<p id="section-boilerplate.1-3">
            Information about the current status of this document, any
            errata, and how to provide feedback on it may be obtained at
            <span><a href="https://www.rfc-editor.org/info/rfc9004">https://www.rfc-editor.org/info/rfc9004</a></span>.<a href="#section-boilerplate.1-3" class="pilcrow">¶</a></p>
</section>
</div>
<div id="copyright">
<section id="section-boilerplate.2">
        <h2 id="name-copyright-notice">
<a href="#name-copyright-notice" class="section-name selfRef">Copyright Notice</a>
        </h2>
<p id="section-boilerplate.2-1">
            Copyright (c) 2021 IETF Trust and the persons identified as the
            document authors. All rights reserved.<a href="#section-boilerplate.2-1" class="pilcrow">¶</a></p>
<p id="section-boilerplate.2-2">
            This document is subject to BCP 78 and the IETF Trust's Legal
            Provisions Relating to IETF Documents
            (<span><a href="https://trustee.ietf.org/license-info">https://trustee.ietf.org/license-info</a></span>) 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.<a href="#section-boilerplate.2-2" class="pilcrow">¶</a></p>
</section>
</div>
<div id="toc">
<section id="section-toc.1">
        <a href="#" onclick="scroll(0,0)" class="toplink">▲</a><h2 id="name-table-of-contents">
<a href="#name-table-of-contents" class="section-name selfRef">Table of Contents</a>
        </h2>
<nav class="toc"><ul class="toc compact ulEmpty">
<li class="toc compact ulEmpty" id="section-toc.1-1.1">
            <p id="section-toc.1-1.1.1" class="keepWithNext"><a href="#section-1" class="xref">1</a>.  <a href="#name-introduction" class="xref">Introduction</a></p>
</li>
          <li class="toc compact ulEmpty" id="section-toc.1-1.2">
            <p id="section-toc.1-1.2.1" class="keepWithNext"><a href="#section-2" class="xref">2</a>.  <a href="#name-requirements-language" class="xref">Requirements Language</a></p>
</li>
          <li class="toc compact ulEmpty" id="section-toc.1-1.3">
            <p id="section-toc.1-1.3.1" class="keepWithNext"><a href="#section-3" class="xref">3</a>.  <a href="#name-scope-and-goals" class="xref">Scope and Goals</a></p>
</li>
          <li class="toc compact ulEmpty" id="section-toc.1-1.4">
            <p id="section-toc.1-1.4.1"><a href="#section-4" class="xref">4</a>.  <a href="#name-motivation" class="xref">Motivation</a></p>
</li>
          <li class="toc compact ulEmpty" id="section-toc.1-1.5">
            <p id="section-toc.1-1.5.1"><a href="#section-5" class="xref">5</a>.  <a href="#name-prerequisites" class="xref">Prerequisites</a></p>
</li>
          <li class="toc compact ulEmpty" id="section-toc.1-1.6">
            <p id="section-toc.1-1.6.1"><a href="#section-6" class="xref">6</a>.  <a href="#name-back-to-back-frames" class="xref">Back-to-Back Frames</a></p>
<ul class="toc compact ulEmpty">
<li class="toc compact ulEmpty" id="section-toc.1-1.6.2.1">
                <p id="section-toc.1-1.6.2.1.1"><a href="#section-6.1" class="xref">6.1</a>.  <a href="#name-preparing-the-list-of-frame" class="xref">Preparing the List of Frame Sizes</a></p>
</li>
              <li class="toc compact ulEmpty" id="section-toc.1-1.6.2.2">
                <p id="section-toc.1-1.6.2.2.1"><a href="#section-6.2" class="xref">6.2</a>.  <a href="#name-test-for-a-single-frame-siz" class="xref">Test for a Single Frame Size</a></p>
</li>
              <li class="toc compact ulEmpty" id="section-toc.1-1.6.2.3">
                <p id="section-toc.1-1.6.2.3.1"><a href="#section-6.3" class="xref">6.3</a>.  <a href="#name-test-repetition-and-benchma" class="xref">Test Repetition and Benchmark</a></p>
</li>
              <li class="toc compact ulEmpty" id="section-toc.1-1.6.2.4">
                <p id="section-toc.1-1.6.2.4.1"><a href="#section-6.4" class="xref">6.4</a>.  <a href="#name-benchmark-calculations" class="xref">Benchmark Calculations</a></p>
</li>
            </ul>
</li>
          <li class="toc compact ulEmpty" id="section-toc.1-1.7">
            <p id="section-toc.1-1.7.1"><a href="#section-7" class="xref">7</a>.  <a href="#name-reporting" class="xref">Reporting</a></p>
</li>
          <li class="toc compact ulEmpty" id="section-toc.1-1.8">
            <p id="section-toc.1-1.8.1"><a href="#section-8" class="xref">8</a>.  <a href="#name-security-considerations" class="xref">Security Considerations</a></p>
</li>
          <li class="toc compact ulEmpty" id="section-toc.1-1.9">
            <p id="section-toc.1-1.9.1"><a href="#section-9" class="xref">9</a>.  <a href="#name-iana-considerations" class="xref">IANA Considerations</a></p>
</li>
          <li class="toc compact ulEmpty" id="section-toc.1-1.10">
            <p id="section-toc.1-1.10.1"><a href="#section-10" class="xref">10</a>. <a href="#name-references" class="xref">References</a></p>
<ul class="toc compact ulEmpty">
<li class="toc compact ulEmpty" id="section-toc.1-1.10.2.1">
                <p id="section-toc.1-1.10.2.1.1"><a href="#section-10.1" class="xref">10.1</a>.  <a href="#name-normative-references" class="xref">Normative References</a></p>
</li>
              <li class="toc compact ulEmpty" id="section-toc.1-1.10.2.2">
                <p id="section-toc.1-1.10.2.2.1"><a href="#section-10.2" class="xref">10.2</a>.  <a href="#name-informative-references" class="xref">Informative References</a></p>
</li>
            </ul>
</li>
          <li class="toc compact ulEmpty" id="section-toc.1-1.11">
            <p id="section-toc.1-1.11.1"><a href="#section-appendix.a" class="xref"></a><a href="#name-acknowledgments" class="xref">Acknowledgments</a></p>
</li>
          <li class="toc compact ulEmpty" id="section-toc.1-1.12">
            <p id="section-toc.1-1.12.1"><a href="#section-appendix.b" class="xref"></a><a href="#name-authors-address" class="xref">Author's Address</a></p>
</li>
        </ul>
</nav>
</section>
</div>
<section id="section-1">
      <h2 id="name-introduction">
<a href="#section-1" class="section-number selfRef">1. </a><a href="#name-introduction" class="section-name selfRef">Introduction</a>
      </h2>
<p id="section-1-1">The IETF's fundamental benchmarking methodologies are defined in
      <span>[<a href="#RFC2544" class="xref">RFC2544</a>]</span>, supported by the terms and definitions
      in <span>[<a href="#RFC1242" class="xref">RFC1242</a>]</span>.  <span>[<a href="#RFC2544" class="xref">RFC2544</a>]</span> actually
      obsoletes an earlier specification, <span>[<a href="#RFC1944" class="xref">RFC1944</a>]</span>. Over time,
      the benchmarking community has updated <span>[<a href="#RFC2544" class="xref">RFC2544</a>]</span> several
      times, including the Device Reset benchmark <span>[<a href="#RFC6201" class="xref">RFC6201</a>]</span>
      and the important Applicability Statement <span>[<a href="#RFC6815" class="xref">RFC6815</a>]</span>
      concerning use outside the Isolated Test Environment (ITE) required for
      accurate benchmarking. Other specifications implicitly update <span>[<a href="#RFC2544" class="xref">RFC2544</a>]</span>, such as the IPv6 benchmarking methodologies in <span>[<a href="#RFC5180" class="xref">RFC5180</a>]</span>.<a href="#section-1-1" class="pilcrow">¶</a></p>
<p id="section-1-2">Recent testing experience with the Back-to-Back Frame test and
      benchmark in <span><a href="https://www.rfc-editor.org/rfc/rfc2544#section-26.4" class="relref">Section 26.4</a> of [<a href="#RFC2544" class="xref">RFC2544</a>]</span> indicates that an
      update is warranted <span>[<a href="#OPNFV-2017" class="xref">OPNFV-2017</a>]</span> <span>[<a href="#VSPERF-b2b" class="xref">VSPERF-b2b</a>]</span>. In particular, analysis of the results indicates
      that buffer size matters when compensating for interruptions of software-packet processing, and this finding increases the importance of the
      Back-to-Back Frame characterization described here. This memo provides
      additional rationale and the updated method.<a href="#section-1-2" class="pilcrow">¶</a></p>
<p id="section-1-3"><span>[<a href="#RFC2544" class="xref">RFC2544</a>]</span> 
      provides its own requirements language consistent with <span>[<a href="#RFC2119" class="xref">RFC2119</a>]</span>, since <span>[<a href="#RFC1944" class="xref">RFC1944</a>]</span> (which it obsoletes) predates <span>[<a href="#RFC2119" class="xref">RFC2119</a>]</span>.  All three memos share common authorship.
      Today, <span>[<a href="#RFC8174" class="xref">RFC8174</a>]</span> clarifies the usage of requirements
      language, so the requirements language presented in this memo are expressed in accordance with
      <span>[<a href="#RFC8174" class="xref">RFC8174</a>]</span>. They are intended for those
      performing/reporting laboratory tests to improve clarity and
      repeatability, and for those designing devices that facilitate these
      tests.<a href="#section-1-3" class="pilcrow">¶</a></p>
</section>
<section id="section-2">
      <h2 id="name-requirements-language">
<a href="#section-2" class="section-number selfRef">2. </a><a href="#name-requirements-language" class="section-name selfRef">Requirements Language</a>
      </h2>
<p id="section-2-1">
    The key words "<span class="bcp14">MUST</span>", "<span class="bcp14">MUST NOT</span>", "<span class="bcp14">REQUIRED</span>", "<span class="bcp14">SHALL</span>", "<span class="bcp14">SHALL NOT</span>", "<span class="bcp14">SHOULD</span>", "<span class="bcp14">SHOULD NOT</span>", "<span class="bcp14">RECOMMENDED</span>", "<span class="bcp14">NOT RECOMMENDED</span>",
    "<span class="bcp14">MAY</span>", and "<span class="bcp14">OPTIONAL</span>" in this document are to be interpreted as
    described in BCP 14 <span>[<a href="#RFC2119" class="xref">RFC2119</a>]</span> <span>[<a href="#RFC8174" class="xref">RFC8174</a>]</span> 
    when, and only when, they appear in all capitals, as shown here.<a href="#section-2-1" class="pilcrow">¶</a></p>
</section>
<section id="section-3">
      <h2 id="name-scope-and-goals">
<a href="#section-3" class="section-number selfRef">3. </a><a href="#name-scope-and-goals" class="section-name selfRef">Scope and Goals</a>
      </h2>
<p id="section-3-1">The scope of this memo is to define an updated method to
      unambiguously perform tests, measure the benchmark(s), and report the
      results for Back-to-Back Frames (as described in
      <span><a href="https://www.rfc-editor.org/rfc/rfc2544#section-26.4" class="relref">Section 26.4</a> of [<a href="#RFC2544" class="xref">RFC2544</a>]</span>).<a href="#section-3-1" class="pilcrow">¶</a></p>
<p id="section-3-2">The goal is to provide more efficient test procedures where possible
      and expand reporting with additional interpretation of the results.
      The tests described in this memo address the cases in which the maximum
      frame rate of a single ingress port cannot be transferred to
      an egress port without loss (for some frame sizes of interest).<a href="#section-3-2" class="pilcrow">¶</a></p>
<p id="section-3-3">Benchmarks as described in <span>[<a href="#RFC2544" class="xref">RFC2544</a>]</span> rely on test conditions with
      constant frame sizes, with the goal of understanding what network-device
      capability has been tested. Tests with the smallest size stress the
      header-processing capacity, and tests with the largest size stress the
      overall bit-processing capacity. Tests with sizes in between may
      determine the transition between these two capacities.
      However,
      conditions simultaneously sending a mixture of Internet (IMIX) frame sizes, such as those described in <span>[<a href="#RFC6985" class="xref">RFC6985</a>]</span>, <span class="bcp14">MUST NOT</span> be
      used in Back-to-Back Frame testing.<a href="#section-3-3" class="pilcrow">¶</a></p>
<p id="section-3-4"><span><a href="https://www.rfc-editor.org/rfc/rfc8239#section-3" class="relref">Section 3</a> of [<a href="#RFC8239" class="xref">RFC8239</a>]</span> describes buffer-size testing
      for physical networking devices in a data center. Those methods measure buffer latency directly with traffic
      on multiple ingress ports that overload an egress port on the Device
      Under Test (DUT) and are not subject to the revised calculations
      presented in this memo. Likewise, the methods of <span>[<a href="#RFC8239" class="xref">RFC8239</a>]</span> <span class="bcp14">SHOULD</span> be used for test cases where the egress-port
      buffer is the known point of overload.<a href="#section-3-4" class="pilcrow">¶</a></p>
</section>
<div id="motivation">
<section id="section-4">
      <h2 id="name-motivation">
<a href="#section-4" class="section-number selfRef">4. </a><a href="#name-motivation" class="section-name selfRef">Motivation</a>
      </h2>
<p id="section-4-1"><span><a href="https://www.rfc-editor.org/rfc/rfc1242#section-3.1" class="relref">Section 3.1</a> of [<a href="#RFC1242" class="xref">RFC1242</a>]</span> describes the rationale for
      the Back-to-Back Frames benchmark. To summarize, there are several
      reasons that devices on a network produce bursts of frames at the
      minimum allowed spacing; and it is, therefore, worthwhile to understand
      the DUT limit on the length of such bursts in
      practice. The same document also states:<a href="#section-4-1" class="pilcrow">¶</a></p>
<blockquote id="section-4-2">
 Tests of this parameter are intended to determine the extent 
      of data buffering in the device.<a href="#section-4-2" class="pilcrow">¶</a>
</blockquote>
<p id="section-4-3">Since this test was defined, there have been occasional discussions
      of the stability and repeatability of the results, both over time and
      across labs. Fortunately, the Open Platform for Network Function
      Virtualization (OPNFV) project on Virtual Switch Performance (VSPERF) Continuous Integration (CI)
      <span>[<a href="#VSPERF-CI" class="xref">VSPERF-CI</a>]</span> testing routinely repeats Back-to-Back Frame
      tests to verify that test functionality has been maintained through
      development of the test-control programs. These tests were used as a
      basis to evaluate stability and repeatability, even across lab setups
      when the test platform was migrated to new DUT hardware at the end of
      2016.<a href="#section-4-3" class="pilcrow">¶</a></p>
<p id="section-4-4">When the VSPERF CI results were examined <span>[<a href="#VSPERF-b2b" class="xref">VSPERF-b2b</a>]</span>,
      several aspects of the results were considered notable:<a href="#section-4-4" class="pilcrow">¶</a></p>
<ol start="1" type="1" class="normal type-1" id="section-4-5">
<li id="section-4-5.1">Back-to-Back Frame benchmark was very consistent for some fixed
          frame sizes, and somewhat variable for other frame sizes.<a href="#section-4-5.1" class="pilcrow">¶</a>
</li>
        <li id="section-4-5.2">The number of Back-to-Back Frames with zero loss reported for
          large frame sizes was unexpectedly long (translating to 30 seconds
          of buffer time), and no explanation or measurement limit condition
          was indicated. It was important that the buffering time calculations
          were part of the referenced testing and analysis <span>[<a href="#VSPERF-b2b" class="xref">VSPERF-b2b</a>]</span>, because the calculated buffer time of
          30 seconds for some frame sizes was clearly wrong or highly
          suspect. On the other hand, a result expressed only as a large
          number of Back-to-Back Frames does not permit such an easy
          comparison with reality.<a href="#section-4-5.2" class="pilcrow">¶</a>
</li>
        <li id="section-4-5.3">Calculation of the extent of buffer time in the DUT helped to
          explain the results observed with all frame sizes. For example,
          tests with some frame sizes cannot exceed the frame-header-processing rate of the DUT, thus, no buffering occurs.  Therefore,
          the results depended on the test equipment and not the DUT.<a href="#section-4-5.3" class="pilcrow">¶</a>
</li>
        <li id="section-4-5.4">It was found that a better estimate of the DUT buffer time could
          be calculated using measurements of both the longest burst in frames
          without loss and results from the Throughput tests conducted
          according to <span><a href="https://www.rfc-editor.org/rfc/rfc2544#section-26.1" class="relref">Section 26.1</a> of [<a href="#RFC2544" class="xref">RFC2544</a>]</span>. It is
          apparent that the DUT's frame-processing rate empties the buffer
          during a trial and tends to increase the "implied" buffer-size
          estimate (measured according to <span><a href="https://www.rfc-editor.org/rfc/rfc2544#section-26.4" class="relref">Section 26.4</a> of [<a href="#RFC2544" class="xref">RFC2544</a>]</span> because many frames have departed the buffer when
          the burst of frames ends). A calculation using the Throughput
          measurement can reveal a "corrected" buffer-size estimate.<a href="#section-4-5.4" class="pilcrow">¶</a>
</li>
      </ol>
<p id="section-4-6">Further, if the Throughput tests of <span><a href="https://www.rfc-editor.org/rfc/rfc2544#section-26.1" class="relref">Section 26.1</a> of [<a href="#RFC2544" class="xref">RFC2544</a>]</span> are conducted as a prerequisite, the number of
      frame sizes required for Back-to-Back Frame benchmarking can be reduced
      to one or more of the small frame sizes, or the results for large frame
      sizes can be noted as invalid in the results if tested anyway. These are
      the larger frame sizes for which the Back-to-Back Frame rate cannot
      exceed the frame-header-processing rate of the DUT and little or no
      buffering occurs.<a href="#section-4-6" class="pilcrow">¶</a></p>
<p id="section-4-7">The material below provides the details of the calculation to
      estimate the actual buffer storage available in the DUT, using results
      from the Throughput tests for each frame size and the Max
      Theoretical Frame Rate for the DUT links (which constrain the minimum
      frame spacing).<a href="#section-4-7" class="pilcrow">¶</a></p>
<p id="section-4-8">In reality, there are many buffers and packet-header-processing steps
      in a typical DUT. The simplified model used in these calculations for
      the DUT includes a packet-header-processing function with limited rate
      of operation, as shown in <a href="#simplified-model" class="xref">Figure 1</a>.<a href="#section-4-8" class="pilcrow">¶</a></p>
<span id="name-simplified-model-for-dut-te"></span><div id="simplified-model">
<figure id="figure-1">
        <div class="artwork art-text alignLeft" id="section-4-9.1">
<pre>
                     |------------ DUT --------|
Generator -&gt; Ingress -&gt; Buffer -&gt; HeaderProc -&gt; Egress -&gt; Receiver
</pre>
</div>
<figcaption><a href="#figure-1" class="selfRef">Figure 1</a>:
<a href="#name-simplified-model-for-dut-te" class="selfRef">Simplified Model for DUT Testing</a>
        </figcaption></figure>
</div>
<p id="section-4-10">So, in the Back-to-Back Frame testing:<a href="#section-4-10" class="pilcrow">¶</a></p>
<ol start="1" type="1" class="normal type-1" id="section-4-11">
<li id="section-4-11.1">The ingress burst arrives at Max Theoretical Frame Rate, and
          initially the frames are buffered.<a href="#section-4-11.1" class="pilcrow">¶</a>
</li>
        <li id="section-4-11.2">The packet-header-processing function (HeaderProc) operates at
          the "Measured Throughput" (<span><a href="https://www.rfc-editor.org/rfc/rfc2544#section-26.1" class="relref">Section 26.1</a> of [<a href="#RFC2544" class="xref">RFC2544</a>]</span>), removing frames from the buffer (this is the
          best approximation we have, another acceptable approximation is the received frame rate 
      during Back-to-back Frame testing, if Measured Throughput is
      not available).<a href="#section-4-11.2" class="pilcrow">¶</a>
</li>
        <li id="section-4-11.3">Frames that have been processed are clearly not in the buffer, so
          the Corrected DUT Buffer Time equation (<a href="#bench-calc" class="xref">Section 6.4</a>) estimates and
          removes the frames that the DUT forwarded on egress during the
          burst. We define buffer time as the number of frames occupying the
          buffer divided by the Max Theoretical Frame Rate (on ingress)
          for the frame size under test.<a href="#section-4-11.3" class="pilcrow">¶</a>
</li>
        <li id="section-4-11.4">A helpful concept is the buffer-filling rate, which is the
          difference between the Max Theoretical Frame Rate (ingress) and the
          Measured Throughput (HeaderProc on egress). If the actual buffer
          size in frames is known, the time to fill the buffer during a
          measurement can be calculated using the filling rate, as a check on
          measurements. However, the buffer in the model represents many
          buffers of different sizes in the DUT data path.<a href="#section-4-11.4" class="pilcrow">¶</a>
</li>
      </ol>
<p id="section-4-12">Knowledge of approximate buffer storage size (in time or bytes) may
      be useful in estimating whether frame losses will occur if DUT forwarding
      is temporarily suspended in a production deployment due to an
      unexpected interruption of frame processing (an interruption of duration
      greater than the estimated buffer would certainly cause lost frames). In
      <a href="#b2b" class="xref">Section 6</a>, the calculations for the correct buffer time use the
      combination of offered load at Max Theoretical Frame Rate and header-processing speed at 100% of Measured Throughput. Other combinations are
      possible, such as changing the percent of Measured Throughput to account
      for other processes reducing the header processing rate.<a href="#section-4-12" class="pilcrow">¶</a></p>
<p id="section-4-13">The presentation of OPNFV VSPERF evaluation and development of
      enhanced search algorithms <span>[<a href="#VSPERF-BSLV" class="xref">VSPERF-BSLV</a>]</span> was given and discussed at
      IETF 102.  The enhancements are intended to compensate for transient
      processor interrupts that may cause loss at near-Throughput levels of offered
      load. Subsequent analysis of the results indicates that buffers within
      the DUT can compensate for some interrupts, and this finding increases
      the importance of the Back-to-Back Frame characterization described
      here.<a href="#section-4-13" class="pilcrow">¶</a></p>
</section>
</div>
<section id="section-5">
      <h2 id="name-prerequisites">
<a href="#section-5" class="section-number selfRef">5. </a><a href="#name-prerequisites" class="section-name selfRef">Prerequisites</a>
      </h2>
<p id="section-5-1">The test setup <span class="bcp14">MUST</span> be consistent with Figure 1 of <span>[<a href="#RFC2544" class="xref">RFC2544</a>]</span>, or Figure 2 of that document when the tester's sender and receiver
      are different devices. Other mandatory testing aspects described in
      <span>[<a href="#RFC2544" class="xref">RFC2544</a>]</span> <span class="bcp14">MUST</span> be included, unless explicitly modified in
      the next section.<a href="#section-5-1" class="pilcrow">¶</a></p>
<p id="section-5-2">The ingress and egress link speeds and link-layer protocols <span class="bcp14">MUST</span> be
      specified and used to compute the Max Theoretical Frame Rate when
      respecting the minimum interframe gap.<a href="#section-5-2" class="pilcrow">¶</a></p>
<p id="section-5-3">The test results for the Throughput benchmark conducted according to
      <span><a href="https://www.rfc-editor.org/rfc/rfc2544#section-26.1" class="relref">Section 26.1</a> of [<a href="#RFC2544" class="xref">RFC2544</a>]</span> for all frame sizes <span class="bcp14">RECOMMENDED</span> by <span>[<a href="#RFC2544" class="xref">RFC2544</a>]</span> <span class="bcp14">MUST</span> be available to reduce
      the tested-frame-size list or to note invalid results for individual
      frame sizes (because the burst length may be essentially infinite for
      large frame sizes).<a href="#section-5-3" class="pilcrow">¶</a></p>
<p id="section-5-4">Note that:<a href="#section-5-4" class="pilcrow">¶</a></p>
<ul class="normal">
<li class="normal" id="section-5-5.1">the Throughput and the Back-to-Back Frame measurement-configuration traffic characteristics (unidirectional or
          bidirectional, and number of flows generated) <span class="bcp14">MUST</span> match.<a href="#section-5-5.1" class="pilcrow">¶</a>
</li>
        <li class="normal" id="section-5-5.2">the Throughput measurement <span class="bcp14">MUST</span> be taken under zero-loss conditions,
          according to <span><a href="https://www.rfc-editor.org/rfc/rfc2544#section-26.1" class="relref">Section 26.1</a> of [<a href="#RFC2544" class="xref">RFC2544</a>]</span>.<a href="#section-5-5.2" class="pilcrow">¶</a>
</li>
      </ul>
<p id="section-5-6">The Back-to-Back Benchmark described in <span><a href="https://www.rfc-editor.org/rfc/rfc1242#section-3.1" class="relref">Section 3.1</a> of [<a href="#RFC1242" class="xref">RFC1242</a>]</span> <span class="bcp14">MUST</span> be measured directly by the tester, where buffer
      size is inferred from Back-to-Back Frame bursts and associated packet-loss measurements. Therefore, sources of frame loss that are unrelated
      to consistent evaluation of buffer size <span class="bcp14">SHOULD</span> be identified and removed
      or mitigated. Example sources include:<a href="#section-5-6" class="pilcrow">¶</a></p>
<ul class="normal">
<li class="normal" id="section-5-7.1">On-path active components that are external to the DUT<a href="#section-5-7.1" class="pilcrow">¶</a>
</li>
        <li class="normal" id="section-5-7.2">Operating-system environment interrupting DUT operation<a href="#section-5-7.2" class="pilcrow">¶</a>
</li>
        <li class="normal" id="section-5-7.3">Shared-resource contention between the DUT and other off-path
          component(s) impacting DUT's behavior, sometimes called the "noisy
          neighbor" problem with virtualized network functions.<a href="#section-5-7.3" class="pilcrow">¶</a>
</li>
      </ul>
<p id="section-5-8">Mitigations applicable to some of the sources above are discussed in
      <a href="#frame-size" class="xref">Section 6.2</a>, with the other measurement requirements described below in
      <a href="#b2b" class="xref">Section 6</a>.<a href="#section-5-8" class="pilcrow">¶</a></p>
</section>
<div id="b2b">
<section id="section-6">
      <h2 id="name-back-to-back-frames">
<a href="#section-6" class="section-number selfRef">6. </a><a href="#name-back-to-back-frames" class="section-name selfRef">Back-to-Back Frames</a>
      </h2>
<p id="section-6-1">Objective: To characterize the ability of a DUT to process
      Back-to-Back Frames as defined in <span>[<a href="#RFC1242" class="xref">RFC1242</a>]</span>.<a href="#section-6-1" class="pilcrow">¶</a></p>
<p id="section-6-2">The procedure follows.<a href="#section-6-2" class="pilcrow">¶</a></p>
<section id="section-6.1">
        <h3 id="name-preparing-the-list-of-frame">
<a href="#section-6.1" class="section-number selfRef">6.1. </a><a href="#name-preparing-the-list-of-frame" class="section-name selfRef">Preparing the List of Frame Sizes</a>
        </h3>
<p id="section-6.1-1">From the list of <span class="bcp14">RECOMMENDED</span> frame sizes (<span><a href="https://www.rfc-editor.org/rfc/rfc2544#section-9" class="relref">Section 9</a> of [<a href="#RFC2544" class="xref">RFC2544</a>]</span>), select the subset of frame sizes whose Measured
        Throughput (during prerequisite testing) was less than the Max
        Theoretical Frame Rate of the DUT/test setup. These are the only
        frame sizes where it is possible to produce a burst of frames that
        cause the DUT buffers to fill and eventually overflow, producing one
        or more discarded frames.<a href="#section-6.1-1" class="pilcrow">¶</a></p>
</section>
<div id="frame-size">
<section id="section-6.2">
        <h3 id="name-test-for-a-single-frame-siz">
<a href="#section-6.2" class="section-number selfRef">6.2. </a><a href="#name-test-for-a-single-frame-siz" class="section-name selfRef">Test for a Single Frame Size</a>
        </h3>
<p id="section-6.2-1">Each trial in the test requires the tester to send a burst of
        frames (after idle time) with the minimum interframe gap and to
        count the corresponding frames forwarded by the DUT.<a href="#section-6.2-1" class="pilcrow">¶</a></p>
<p id="section-6.2-2">The duration of the trial includes three <span class="bcp14">REQUIRED</span> components:<a href="#section-6.2-2" class="pilcrow">¶</a></p>
<ol start="1" type="1" class="normal type-1" id="section-6.2-3">
<li id="section-6.2-3.1">The time to send the burst of frames (at the back-to-back
            rate), determined by the search algorithm.<a href="#section-6.2-3.1" class="pilcrow">¶</a>
</li>
          <li id="section-6.2-3.2">The time to receive the transferred burst of frames (at the
            <span>[<a href="#RFC2544" class="xref">RFC2544</a>]</span> Throughput rate), possibly truncated by
            buffer overflow, and certainly including the latency of the
            DUT.<a href="#section-6.2-3.2" class="pilcrow">¶</a>
</li>
          <li id="section-6.2-3.3">At least 2 seconds not overlapping the time to receive the
            burst (Component 2, above), to ensure that DUT buffers have depleted. Longer times
            <span class="bcp14">MUST</span> be used when conditions warrant, such as when buffer times
            &gt;2 seconds are measured or when burst sending times are &gt;2
            seconds, but care is needed, since this time component directly
            increases trial duration, and many trials and tests comprise a
            complete benchmarking study.<a href="#section-6.2-3.3" class="pilcrow">¶</a>
</li>
        </ol>
<p id="section-6.2-4">The upper search limit for the time to send each burst <span class="bcp14">MUST</span>
        be configurable to values as high as 30 seconds (buffer time results
        reported at or near the configured upper limit are likely invalid, and
        the test <span class="bcp14">MUST</span> be repeated with a higher search limit).<a href="#section-6.2-4" class="pilcrow">¶</a></p>
<p id="section-6.2-5">If all frames have been received, the tester increases the length
        of the burst according to the search algorithm and performs another
        trial.<a href="#section-6.2-5" class="pilcrow">¶</a></p>
<p id="section-6.2-6">If the received frame count is less than the number of frames in
        the burst, then the limit of DUT processing and buffering may have
        been exceeded, and the burst length for the next trial is determined by the search
        algorithm (the burst length is typically reduced,
        but see below).<a href="#section-6.2-6" class="pilcrow">¶</a></p>
<p id="section-6.2-7">Classic search algorithms have been adapted for use in
        benchmarking, where the search requires discovery of a pair of
        outcomes, one with no loss and another with loss, at load conditions
        within the acceptable tolerance or accuracy. Conditions encountered
        when benchmarking the infrastructure for network function
        virtualization require algorithm enhancement. Fortunately, the
        adaptation of Binary Search, and an enhanced Binary Search with Loss
        Verification, have been specified in Clause 12.3 of <span>[<a href="#TST009" class="xref">TST009</a>]</span>. These algorithms can easily be used for
        Back-to-Back Frame benchmarking by replacing the offered load level
        with burst length in frames. <span>[<a href="#TST009" class="xref">TST009</a>]</span>, Annex B describes
        the theory behind the enhanced Binary Search with Loss Verification
        algorithm.<a href="#section-6.2-7" class="pilcrow">¶</a></p>
<p id="section-6.2-8">There are also promising works in progress that may prove useful in
        Back-to-Back Frame benchmarking. <span>[<a href="#I-D.ietf-bmwg-mlrsearch" class="xref">BMWG-MLRSEARCH</a>]</span> and <span>[<a href="#I-D.vpolak-bmwg-plrsearch" class="xref">BMWG-PLRSEARCH</a>]</span> are two such examples.<a href="#section-6.2-8" class="pilcrow">¶</a></p>
<p id="section-6.2-9">Either the <span>[<a href="#TST009" class="xref">TST009</a>]</span> Binary Search or Binary Search
        with Loss Verification algorithms <span class="bcp14">MUST</span> be used, and input parameters
        to the algorithm(s) <span class="bcp14">MUST</span> be reported.<a href="#section-6.2-9" class="pilcrow">¶</a></p>
<p id="section-6.2-10">The tester usually imposes a (configurable) minimum step size for
        burst length, and the step size <span class="bcp14">MUST</span> be reported with the results (as
        this influences the accuracy and variation of test results).<a href="#section-6.2-10" class="pilcrow">¶</a></p>
<p id="section-6.2-11">The original <span><a href="https://www.rfc-editor.org/rfc/rfc2544#section-26.4" class="relref">Section 26.4</a> of [<a href="#RFC2544" class="xref">RFC2544</a>]</span> definition is
        stated below:<a href="#section-6.2-11" class="pilcrow">¶</a></p>
<blockquote id="section-6.2-12">
   The back-to-back value is the number of frames in the longest burst that the DUT will handle without the loss of any frames.<a href="#section-6.2-12" class="pilcrow">¶</a>
</blockquote>
</section>
</div>
<div id="test-rep">
<section id="section-6.3">
        <h3 id="name-test-repetition-and-benchma">
<a href="#section-6.3" class="section-number selfRef">6.3. </a><a href="#name-test-repetition-and-benchma" class="section-name selfRef">Test Repetition and Benchmark</a>
        </h3>
<p id="section-6.3-1">On this topic, <span><a href="https://www.rfc-editor.org/rfc/rfc2544#section-26.4" class="relref">Section 26.4</a> of [<a href="#RFC2544" class="xref">RFC2544</a>]</span>
        requires:<a href="#section-6.3-1" class="pilcrow">¶</a></p>
<blockquote id="section-6.3-2">
          The trial length <span class="bcp14">MUST</span> be at least 2 seconds and <span class="bcp14">SHOULD</span> be
            repeated at least 50 times with the average of the recorded values
            being reported.<a href="#section-6.3-2" class="pilcrow">¶</a>
</blockquote>
<p id="section-6.3-3">Therefore, the Back-to-Back Frame benchmark is the average of burst-length values over repeated tests to determine the longest burst of
        frames that the DUT can successfully process and buffer without frame
        loss. Each of the repeated tests completes an independent search
        process.<a href="#section-6.3-3" class="pilcrow">¶</a></p>
<p id="section-6.3-4">In this update, the test <span class="bcp14">MUST</span> be repeated N times (the number of
        repetitions is now a variable that must be reported) for each frame
        size in the subset list, and each Back-to-Back Frame value <span class="bcp14">MUST</span> be made
        available for further processing (below).<a href="#section-6.3-4" class="pilcrow">¶</a></p>
</section>
</div>
<div id="bench-calc">
<section id="section-6.4">
        <h3 id="name-benchmark-calculations">
<a href="#section-6.4" class="section-number selfRef">6.4. </a><a href="#name-benchmark-calculations" class="section-name selfRef">Benchmark Calculations</a>
        </h3>
<p id="section-6.4-1">For each frame size, calculate the following summary statistics for
        longest Back-to-Back Frame values over the N tests:<a href="#section-6.4-1" class="pilcrow">¶</a></p>
<ul class="normal">
<li class="normal" id="section-6.4-2.1">Average (Benchmark)<a href="#section-6.4-2.1" class="pilcrow">¶</a>
</li>
          <li class="normal" id="section-6.4-2.2">Minimum<a href="#section-6.4-2.2" class="pilcrow">¶</a>
</li>
          <li class="normal" id="section-6.4-2.3">Maximum<a href="#section-6.4-2.3" class="pilcrow">¶</a>
</li>
          <li class="normal" id="section-6.4-2.4">Standard Deviation<a href="#section-6.4-2.4" class="pilcrow">¶</a>
</li>
        </ul>
<p id="section-6.4-3">Further, calculate the Implied DUT Buffer Time and the Corrected
        DUT Buffer Time in seconds, as follows:<a href="#section-6.4-3" class="pilcrow">¶</a></p>
<div class="artwork art-text alignLeft" id="section-6.4-4">
<pre>
Implied DUT buffer time =

   Average num of Back-to-back Frames / Max Theoretical Frame Rate
</pre><a href="#section-6.4-4" class="pilcrow">¶</a>
</div>
<p id="section-6.4-5">The formula above is simply expressing the burst of frames
        in units of time.<a href="#section-6.4-5" class="pilcrow">¶</a></p>
<p id="section-6.4-6">The next step is to apply a correction factor that accounts for the
        DUT's frame forwarding operation during the test (assuming the simple
        model of the DUT composed of a buffer and a forwarding function,
        described in <a href="#motivation" class="xref">Section 4</a>).<a href="#section-6.4-6" class="pilcrow">¶</a></p>
<div class="artwork art-text alignLeft" id="section-6.4-7">
<pre>Corrected DUT Buffer Time =
                  /                                         \
   Implied DUT    |Implied DUT       Measured Throughput    |
=  Buffer Time -  |Buffer Time * -------------------------- |
                  |              Max Theoretical Frame Rate |
                  \                                         /</pre><a href="#section-6.4-7" class="pilcrow">¶</a>
</div>
<p id="section-6.4-8">where:<a href="#section-6.4-8" class="pilcrow">¶</a></p>
<ol start="1" type="1" class="normal type-1" id="section-6.4-9">
<li id="section-6.4-9.1">The "Measured Throughput" is the <span>[<a href="#RFC2544" class="xref">RFC2544</a>]</span> Throughput Benchmark for the frame size tested,
            as augmented by methods including the Binary Search with Loss
            Verification algorithm in <span>[<a href="#TST009" class="xref">TST009</a>]</span> where
            applicable and <span class="bcp14">MUST</span> be expressed in frames per second in this
            equation.<a href="#section-6.4-9.1" class="pilcrow">¶</a>
</li>
          <li id="section-6.4-9.2">The "Max Theoretical Frame Rate" is a calculated
            value for the interface speed and link-layer technology used, and it
            <span class="bcp14">MUST</span> be expressed in frames per second in this equation.<a href="#section-6.4-9.2" class="pilcrow">¶</a>
</li>
        </ol>
<p id="section-6.4-10">The term on the far right in the formula for Corrected DUT Buffer
        Time accounts for all the frames in the burst that were transmitted by
        the DUT <strong>while the burst of frames was sent in</strong>.  So, these frames are
        not in the buffer, and the buffer size is more accurately estimated by
        excluding them.  If Measured Throughput is not available,
  an acceptable approximation is the received frame rate (see Forwarding 
  Rate in <span>[<a href="#RFC2889" class="xref">RFC2889</a>]</span> measured during Back-to-back Frame testing).<a href="#section-6.4-10" class="pilcrow">¶</a></p>
</section>
</div>
</section>
</div>
<section id="section-7">
      <h2 id="name-reporting">
<a href="#section-7" class="section-number selfRef">7. </a><a href="#name-reporting" class="section-name selfRef">Reporting</a>
      </h2>
<p id="section-7-1">The Back-to-Back Frame results <span class="bcp14">SHOULD</span> be reported in the format of a
      table with a row for each of the tested frame sizes. There <span class="bcp14">SHOULD</span> be
      columns for the frame size and the resultant average frame count for
      each type of data stream tested.<a href="#section-7-1" class="pilcrow">¶</a></p>
<p id="section-7-2">The number of tests averaged for the benchmark, N, <span class="bcp14">MUST</span> be
      reported.<a href="#section-7-2" class="pilcrow">¶</a></p>
<p id="section-7-3">The minimum, maximum, and standard deviation across all complete
      tests <span class="bcp14">SHOULD</span> also be reported (they are referred to as "Min,Max,StdDev"
      in <a href="#frame-results" class="xref">Table 1</a>).<a href="#section-7-3" class="pilcrow">¶</a></p>
<p id="section-7-4">The Corrected DUT Buffer Time <span class="bcp14">SHOULD</span> also be reported.<a href="#section-7-4" class="pilcrow">¶</a></p>
<p id="section-7-5">If the tester operates using a limited maximum burst length in
      frames, then this maximum length <span class="bcp14">SHOULD</span> be reported.<a href="#section-7-5" class="pilcrow">¶</a></p>
<span id="name-back-to-back-frame-results"></span><div id="frame-results">
<table class="center" id="table-1">
        <caption>
<a href="#table-1" class="selfRef">Table 1</a>:
<a href="#name-back-to-back-frame-results" class="selfRef">Back-to-Back Frame Results</a>
        </caption>
<thead>
          <tr>
            <th class="text-left" rowspan="1" colspan="1">Frame Size, octets</th>
            <th class="text-left" rowspan="1" colspan="1">Ave B2B Length, frames</th>
            <th class="text-left" rowspan="1" colspan="1">Min,Max,StdDev</th>
            <th class="text-left" rowspan="1" colspan="1">Corrected Buff Time, Sec</th>
          </tr>
        </thead>
        <tbody>
          <tr>
            <td class="text-left" rowspan="1" colspan="1">64</td>
            <td class="text-left" rowspan="1" colspan="1">26000</td>
            <td class="text-left" rowspan="1" colspan="1">25500,27000,20</td>
            <td class="text-left" rowspan="1" colspan="1">0.00004</td>
          </tr>
        </tbody>
      </table>
</div>
<p id="section-7-7">Static and configuration parameters (reported with <a href="#frame-results" class="xref">Table 1</a>):<a href="#section-7-7" class="pilcrow">¶</a></p>
<ul class="normal">
<li class="normal" id="section-7-8.1">Number of test repetitions, N<a href="#section-7-8.1" class="pilcrow">¶</a>
</li>
        <li class="normal" id="section-7-8.2">Minimum Step Size (during searches), in frames.<a href="#section-7-8.2" class="pilcrow">¶</a>
</li>
      </ul>
<p id="section-7-9"></p>
<p id="section-7-10">If the tester has a specific (actual) frame rate of interest (less
      than the Throughput rate), it is useful to estimate the buffer time at
      that actual frame rate:<a href="#section-7-10" class="pilcrow">¶</a></p>
<div class="artwork art-text alignLeft" id="section-7-11">
<pre>Actual Buffer Time =
                                   Max Theoretical Frame Rate
     = Corrected DUT Buffer Time * --------------------------
                                       Actual Frame Rate
</pre><a href="#section-7-11" class="pilcrow">¶</a>
</div>
<p id="section-7-12">and report this value, properly labeled.<a href="#section-7-12" class="pilcrow">¶</a></p>
</section>
<section id="section-8">
      <h2 id="name-security-considerations">
<a href="#section-8" class="section-number selfRef">8. </a><a href="#name-security-considerations" class="section-name selfRef">Security Considerations</a>
      </h2>
<p id="section-8-1">Benchmarking activities as described in this memo are limited to
      technology characterization using controlled stimuli in a laboratory
      environment, with dedicated address space and the other constraints
      of <span>[<a href="#RFC2544" class="xref">RFC2544</a>]</span>.<a href="#section-8-1" class="pilcrow">¶</a></p>
<p id="section-8-2">The benchmarking network topology will be an independent test setup
      and <span class="bcp14">MUST NOT</span> be connected to devices that may forward the test traffic
      into a production network or misroute traffic to the test management
      network. See <span>[<a href="#RFC6815" class="xref">RFC6815</a>]</span>.<a href="#section-8-2" class="pilcrow">¶</a></p>
<p id="section-8-3">Further, benchmarking is performed on an "opaque-box" (a.k.a.
      "black-box") basis, relying solely on measurements observable external
      to the Device or System Under Test (SUT).<a href="#section-8-3" class="pilcrow">¶</a></p>
<p id="section-8-4">The DUT developers are commonly independent from the personnel and
      institutions conducting benchmarking studies. DUT developers might have
      incentives to alter the performance of the DUT if the test conditions
      can be detected. Special capabilities <span class="bcp14">SHOULD NOT</span> exist in the DUT/SUT
      specifically for benchmarking purposes. Procedures described in this
      document are not designed to detect such activity. Additional testing
      outside of the scope of this document would be needed and has been used
      successfully in the past to discover such malpractices.<a href="#section-8-4" class="pilcrow">¶</a></p>
<p id="section-8-5">Any implications for network security arising from the DUT/SUT <span class="bcp14">SHOULD</span>
      be identical in the lab and in production networks.<a href="#section-8-5" class="pilcrow">¶</a></p>
</section>
<div id="IANA">
<section id="section-9">
      <h2 id="name-iana-considerations">
<a href="#section-9" class="section-number selfRef">9. </a><a href="#name-iana-considerations" class="section-name selfRef">IANA Considerations</a>
      </h2>
<p id="section-9-1">This document has no IANA actions.<a href="#section-9-1" class="pilcrow">¶</a></p>
</section>
</div>
<section id="section-10">
      <h2 id="name-references">
<a href="#section-10" class="section-number selfRef">10. </a><a href="#name-references" class="section-name selfRef">References</a>
      </h2>
<section id="section-10.1">
        <h3 id="name-normative-references">
<a href="#section-10.1" class="section-number selfRef">10.1. </a><a href="#name-normative-references" class="section-name selfRef">Normative References</a>
        </h3>
<dl class="references">
<dt id="RFC1242">[RFC1242]</dt>
        <dd>
<span class="refAuthor">Bradner, S.</span>, <span class="refTitle">"Benchmarking Terminology for Network Interconnection Devices"</span>, <span class="seriesInfo">RFC 1242</span>, <span class="seriesInfo">DOI 10.17487/RFC1242</span>, <time datetime="1991-07" class="refDate">July 1991</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc1242">https://www.rfc-editor.org/info/rfc1242</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC2119">[RFC2119]</dt>
        <dd>
<span class="refAuthor">Bradner, S.</span>, <span class="refTitle">"Key words for use in RFCs to Indicate Requirement Levels"</span>, <span class="seriesInfo">BCP 14</span>, <span class="seriesInfo">RFC 2119</span>, <span class="seriesInfo">DOI 10.17487/RFC2119</span>, <time datetime="1997-03" class="refDate">March 1997</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc2119">https://www.rfc-editor.org/info/rfc2119</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC2544">[RFC2544]</dt>
        <dd>
<span class="refAuthor">Bradner, S.</span> and <span class="refAuthor">J. McQuaid</span>, <span class="refTitle">"Benchmarking Methodology for Network Interconnect Devices"</span>, <span class="seriesInfo">RFC 2544</span>, <span class="seriesInfo">DOI 10.17487/RFC2544</span>, <time datetime="1999-03" class="refDate">March 1999</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc2544">https://www.rfc-editor.org/info/rfc2544</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC6985">[RFC6985]</dt>
        <dd>
<span class="refAuthor">Morton, A.</span>, <span class="refTitle">"IMIX Genome: Specification of Variable Packet Sizes for Additional Testing"</span>, <span class="seriesInfo">RFC 6985</span>, <span class="seriesInfo">DOI 10.17487/RFC6985</span>, <time datetime="2013-07" class="refDate">July 2013</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc6985">https://www.rfc-editor.org/info/rfc6985</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC8174">[RFC8174]</dt>
        <dd>
<span class="refAuthor">Leiba, B.</span>, <span class="refTitle">"Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words"</span>, <span class="seriesInfo">BCP 14</span>, <span class="seriesInfo">RFC 8174</span>, <span class="seriesInfo">DOI 10.17487/RFC8174</span>, <time datetime="2017-05" class="refDate">May 2017</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8174">https://www.rfc-editor.org/info/rfc8174</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC8239">[RFC8239]</dt>
        <dd>
<span class="refAuthor">Avramov, L.</span> and <span class="refAuthor">J. Rapp</span>, <span class="refTitle">"Data Center Benchmarking Methodology"</span>, <span class="seriesInfo">RFC 8239</span>, <span class="seriesInfo">DOI 10.17487/RFC8239</span>, <time datetime="2017-08" class="refDate">August 2017</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc8239">https://www.rfc-editor.org/info/rfc8239</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="TST009">[TST009]</dt>
      <dd>
<span class="refAuthor">ETSI</span>, <span class="refTitle">"Network Functions Virtualisation (NFV) Release 3; Testing; Specification of Networking Benchmarks and Measurement Methods for NFVI"</span>, <span class="refContent">Rapporteur: A. Morton</span>, <span class="seriesInfo">ETSI GS NFV-TST 009 v3.4.1</span>, <time datetime="2020-12" class="refDate">December 2020</time>, <span>&lt;<a href="https://www.etsi.org/deliver/etsi_gs/NFV-TST/001_099/009/03.04.01_60/gs_NFV-TST009v030401p.pdf">https://www.etsi.org/deliver/etsi_gs/NFV-TST/001_099/009/03.04.01_60/gs_NFV-TST009v030401p.pdf</a>&gt;</span>. </dd>
<dd class="break"></dd>
</dl>
</section>
<section id="section-10.2">
        <h3 id="name-informative-references">
<a href="#section-10.2" class="section-number selfRef">10.2. </a><a href="#name-informative-references" class="section-name selfRef">Informative References</a>
        </h3>
<dl class="references">
<dt id="I-D.ietf-bmwg-mlrsearch">[BMWG-MLRSEARCH]</dt>
        <dd>
<span class="refAuthor">Konstantynowicz, M., Ed.</span> and <span class="refAuthor">V. Polák, Ed.</span>, <span class="refTitle">"Multiple Loss Ratio Search for Packet Throughput (MLRsearch)"</span>, <span class="refContent">Work in Progress</span>, <span class="seriesInfo">Internet-Draft, draft-ietf-bmwg-mlrsearch-00</span>, <time datetime="2021-02-09" class="refDate">9 February 2021</time>, <span>&lt;<a href="https://tools.ietf.org/html/draft-ietf-bmwg-mlrsearch-00">https://tools.ietf.org/html/draft-ietf-bmwg-mlrsearch-00</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="I-D.vpolak-bmwg-plrsearch">[BMWG-PLRSEARCH]</dt>
        <dd>
<span class="refAuthor">Konstantynowicz, M., Ed.</span> and <span class="refAuthor">V. Polák, Ed.</span>, <span class="refTitle">"Probabilistic Loss Ratio Search for Packet Throughput (PLRsearch)"</span>, <span class="refContent">Work in Progress</span>, <span class="seriesInfo">Internet-Draft, draft-vpolak-bmwg-plrsearch-03</span>, <time datetime="2020-03-06" class="refDate">6 March 2020</time>, <span>&lt;<a href="https://tools.ietf.org/html/draft-vpolak-bmwg-plrsearch-03">https://tools.ietf.org/html/draft-vpolak-bmwg-plrsearch-03</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="OPNFV-2017">[OPNFV-2017]</dt>
        <dd>
<span class="refAuthor">Cooper, T.</span>, <span class="refAuthor">Rao, S.</span>, and <span class="refAuthor">A. Morton</span>, <span class="refTitle">"Dataplane Performance, Capacity, and Benchmarking in OPNFV"</span>, <time datetime="2017-06-15" class="refDate">15 June 2017</time>, <span>&lt;<a href="https://wiki.anuket.io/download/attachments/4404001/VSPERF-Dataplane-Perf-Cap-Bench.pdf?version=1&amp;modificationDate=1621191833500&amp;api=v2">https://wiki.anuket.io/download/attachments/4404001/VSPERF-Dataplane-Perf-Cap-Bench.pdf?version=1&amp;modificationDate=1621191833500&amp;api=v2</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC1944">[RFC1944]</dt>
        <dd>
<span class="refAuthor">Bradner, S.</span> and <span class="refAuthor">J. McQuaid</span>, <span class="refTitle">"Benchmarking Methodology for Network Interconnect Devices"</span>, <span class="seriesInfo">RFC 1944</span>, <span class="seriesInfo">DOI 10.17487/RFC1944</span>, <time datetime="1996-05" class="refDate">May 1996</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc1944">https://www.rfc-editor.org/info/rfc1944</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC2889">[RFC2889]</dt>
        <dd>
<span class="refAuthor">Mandeville, R.</span> and <span class="refAuthor">J. Perser</span>, <span class="refTitle">"Benchmarking Methodology for LAN Switching Devices"</span>, <span class="seriesInfo">RFC 2889</span>, <span class="seriesInfo">DOI 10.17487/RFC2889</span>, <time datetime="2000-08" class="refDate">August 2000</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc2889">https://www.rfc-editor.org/info/rfc2889</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC5180">[RFC5180]</dt>
        <dd>
<span class="refAuthor">Popoviciu, C.</span>, <span class="refAuthor">Hamza, A.</span>, <span class="refAuthor">Van de Velde, G.</span>, and <span class="refAuthor">D. Dugatkin</span>, <span class="refTitle">"IPv6 Benchmarking Methodology for Network Interconnect Devices"</span>, <span class="seriesInfo">RFC 5180</span>, <span class="seriesInfo">DOI 10.17487/RFC5180</span>, <time datetime="2008-05" class="refDate">May 2008</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc5180">https://www.rfc-editor.org/info/rfc5180</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC6201">[RFC6201]</dt>
        <dd>
<span class="refAuthor">Asati, R.</span>, <span class="refAuthor">Pignataro, C.</span>, <span class="refAuthor">Calabria, F.</span>, and <span class="refAuthor">C. Olvera</span>, <span class="refTitle">"Device Reset Characterization"</span>, <span class="seriesInfo">RFC 6201</span>, <span class="seriesInfo">DOI 10.17487/RFC6201</span>, <time datetime="2011-03" class="refDate">March 2011</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc6201">https://www.rfc-editor.org/info/rfc6201</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="RFC6815">[RFC6815]</dt>
        <dd>
<span class="refAuthor">Bradner, S.</span>, <span class="refAuthor">Dubray, K.</span>, <span class="refAuthor">McQuaid, J.</span>, and <span class="refAuthor">A. Morton</span>, <span class="refTitle">"Applicability Statement for RFC 2544: Use on Production Networks Considered Harmful"</span>, <span class="seriesInfo">RFC 6815</span>, <span class="seriesInfo">DOI 10.17487/RFC6815</span>, <time datetime="2012-11" class="refDate">November 2012</time>, <span>&lt;<a href="https://www.rfc-editor.org/info/rfc6815">https://www.rfc-editor.org/info/rfc6815</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="VSPERF-b2b">[VSPERF-b2b]</dt>
        <dd>
<span class="refAuthor">Morton, A.</span>, <span class="refTitle">"Back2Back Testing Time Series (from CI)"</span>, <time datetime="2021-05" class="refDate">May 2021</time>, <span>&lt;<a href="https://wiki.anuket.io/display/HOME/Traffic+Generator+Testing#TrafficGeneratorTesting-AppendixB:Back2BackTestingTimeSeries(fromCI)">https://wiki.anuket.io/display/HOME/Traffic+Generator+Testing#TrafficGeneratorTesting-AppendixB:Back2BackTestingTimeSeries(fromCI)</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="VSPERF-BSLV">[VSPERF-BSLV]</dt>
        <dd>
<span class="refAuthor">Rao, S.</span> and <span class="refAuthor">A. Morton</span>, <span class="refTitle">"Evolution of Repeatability in Benchmarking: Fraser Plugfest (Summary for IETF BMWG)"</span>, <time datetime="2018-07" class="refDate">July 2018</time>, <span>&lt;<a href="https://datatracker.ietf.org/meeting/102/materials/slides-102-bmwg-evolution-of-repeatability-in-benchmarking-fraser-plugfest-summary-for-ietf-bmwg-00">https://datatracker.ietf.org/meeting/102/materials/slides-102-bmwg-evolution-of-repeatability-in-benchmarking-fraser-plugfest-summary-for-ietf-bmwg-00</a>&gt;</span>. </dd>
<dd class="break"></dd>
<dt id="VSPERF-CI">[VSPERF-CI]</dt>
      <dd>
<span class="refAuthor">Tahhan, M.</span>, <span class="refTitle">"OPNFV VSPERF CI"</span>, <time datetime="2019-09" class="refDate">September 2019</time>, <span>&lt;<a href="https://wiki.anuket.io/display/HOME/VSPERF+CI">https://wiki.anuket.io/display/HOME/VSPERF+CI</a>&gt;</span>. </dd>
<dd class="break"></dd>
</dl>
</section>
</section>
<section id="section-appendix.a">
      <h2 id="name-acknowledgments">
<a href="#name-acknowledgments" class="section-name selfRef">Acknowledgments</a>
      </h2>
<p id="section-appendix.a-1">Thanks to <span class="contact-name">Trevor Cooper</span>, <span class="contact-name">Sridhar Rao</span>, and <span class="contact-name">Martin Klozik</span> of the VSPERF
      project for many contributions to the early testing <span>[<a href="#VSPERF-b2b" class="xref">VSPERF-b2b</a>]</span>. <span class="contact-name">Yoshiaki Itou</span> has also investigated the topic
      and made useful suggestions. <span class="contact-name">Maciek Konstantyowicz</span> and <span class="contact-name">Vratko Polák</span> also
      provided many comments and suggestions based on extensive integration
      testing and resulting search-algorithm proposals -- the most up-to-date
      feedback possible. <span class="contact-name">Tim Carlin</span> also provided comments and support for the
      document. <span class="contact-name">Warren Kumari</span>'s review improved readability in several key
      passages. <span class="contact-name">David Black</span>, <span class="contact-name">Martin Duke</span>, and <span class="contact-name">Scott Bradner</span>'s comments
      improved the clarity and configuration advice on trial duration. <span class="contact-name">Mališa Vučinić</span> suggested additional text on DUT design cautions in the Security
      Considerations section.<a href="#section-appendix.a-1" class="pilcrow">¶</a></p>
</section>
<div id="authors-addresses">
<section id="section-appendix.b">
      <h2 id="name-authors-address">
<a href="#name-authors-address" class="section-name selfRef">Author's Address</a>
      </h2>
<address class="vcard">
        <div dir="auto" class="left"><span class="fn nameRole">Al Morton</span></div>
<div dir="auto" class="left"><span class="org">AT&amp;T Labs</span></div>
<div dir="auto" class="left"><span class="street-address">200 Laurel Avenue South</span></div>
<div dir="auto" class="left">
<span class="locality">Middletown</span>, <span class="region">NJ</span> <span class="postal-code">07748</span>
</div>
<div dir="auto" class="left"><span class="country-name">United States of America</span></div>
<div class="tel">
<span>Phone:</span>
<a href="tel:+1%20732%20420%201571" class="tel">+1 732 420 1571</a>
</div>
<div class="email">
<span>Email:</span>
<a href="mailto:acmorton@att.com" class="email">acmorton@att.com</a>
</div>
</address>
</section>
</div>
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