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#
# Copyright (c) 1999 Regents of the University of California.
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
# 3. All advertising materials mentioning features or use of this software
# must display the following acknowledgement:
# This product includes software developed by the MASH Research
# Group at the University of California Berkeley.
# 4. Neither the name of the University nor of the Research Group may be
# used to endorse or promote products derived from this software without
# specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
#
# Contributed by Tom Henderson, UCB Daedalus Research Group, June 1999
#
# $Header: /cvsroot/nsnam/ns-2/tcl/ex/sat-aloha.tcl,v 1.5 2001/11/06 06:20:11 tomh Exp $
#
# Simple script with a geostationary bent-pipe (repeater) satellite and
# one hundred terminals using unslotted (pure) Aloha random access. The
# traffic sources consist of exponential on-off traffic generators unless
# indicated below. With the traffic rates configured below, approximately
# one tenth of the packets collide and must be retransmitted.
#
# Tests:
# 1. basic: Mac operates in stop-and-wait mode (one outstanding packet
# at a time). Collisions and drops are not traced. This test
# should provide similar results to the satellite test suite.
# 2. basic_tracing: Same as "basic", but drops ("d") and collisions ("c")
# are instead explicitly traced. Again, similar to test suite
# 3. poisson: Packets arrive according to Poisson process. Each source
# still operates in stop-and-wait mode, and collisions and
# drops are traced. rtx_limit_ == 0 (no persistence).
# This can be used to try to approximate theoretical
# unslotted Aloha results, if the number of terminals is large
# compared to the arrival rate (so that no packets are queued)
# 4. [FOR FUTURE WORK]. (larger than one packet rxmit buffer, different
# traffic generator?)
#
if { $argc != 1 } {
puts stderr {usage: ns sat-aloha.tcl [basic basic_tracing poisson]}
exit 1
}
set test_ $argv
puts "Running test $test_ ..."
global ns
set ns [new Simulator]
# Global configuration parameters for Aloha (also settable in ns-sat.tcl)
Mac/Sat/UnslottedAloha set mean_backoff_ 1s ; # mean exponential backoff time(s)
Mac/Sat/UnslottedAloha set rtx_limit_ 3; # max number of retrans. attempted
Mac/Sat/UnslottedAloha set send_timeout_ 270ms; # resend if send times out
if { $test_ == "basic"} {
Mac/Sat set trace_collisions_ false
Mac/Sat set trace_drops_ false
}
global opt
set opt(chan) Channel/Sat
set opt(bw_up) 2Mb
set opt(bw_down) 2Mb
set opt(phy) Phy/Sat
set opt(mac) Mac/Sat/UnslottedAloha
set opt(ifq) Queue/DropTail
set opt(qlim) 50
set opt(ll) LL/Sat
set opt(wiredRouting) OFF
# XXX This tracing enabling must precede link and node creation
set outfile [open out.tr w]
$ns trace-all $outfile
# Set up satellite and terrestrial nodes
# GEO satellite at 0 degrees longitude
$ns node-config -satNodeType geo-repeater \
-llType $opt(ll) \
-ifqType $opt(ifq) \
-ifqLen $opt(qlim) \
-macType $opt(mac) \
-phyType $opt(phy) \
-channelType $opt(chan) \
-downlinkBW $opt(bw_down) \
-wiredRouting $opt(wiredRouting)
set n1 [$ns node]
$n1 set-position 0
# Place 50 terminals at 100 different locations
$ns node-config -satNodeType terminal
set num_nodes 100
for {set a 1} {$a <= $num_nodes} {incr a} {
set n($a) [$ns node]
$n($a) set-position [expr -15 + $a * 0.3] [expr 15 - $a * 0.3]
$n($a) add-gsl geo $opt(ll) $opt(ifq) $opt(qlim) $opt(mac) $opt(bw_up) \
$opt(phy) [$n1 set downlink_] [$n1 set uplink_]
}
for {set a 1} {$a <= $num_nodes} {incr a} {
set b [expr int($a + (0.5 * $num_nodes))]
if {$b > $num_nodes} {
incr b [expr -1 * $num_nodes]
}
set udp($a) [new Agent/UDP]
$ns attach-agent $n($a) $udp($a)
set exp($a) [new Application/Traffic/Exponential]
$exp($a) attach-agent $udp($a)
$exp($a) set rate_ 1Kb
if {$test_ == "poisson"} {
$exp($a) set rate_ 10000Mb
$exp($a) set burst_time_ 0
$exp($a) set idle_time_ 5
}
set null($a) [new Agent/Null]
$ns attach-agent $n($b) $null($a)
$ns connect $udp($a) $null($a)
$ns at 1.0 "$exp($a) start"
}
$ns trace-all-satlinks $outfile
# We use centralized routing
set satrouteobject_ [new SatRouteObject]
$satrouteobject_ compute_routes
$ns at 100.0 "finish"
proc finish {} {
global ns outfile
$ns flush-trace
close $outfile
exit 0
}
$ns run
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