为了自己的MANET研究，最近一直做网络仿真。第一步就想做一个DSR路由协议的模拟。遗憾的是，例子中的代码实在是太简单了，根本没有实现多跳功能。网上找了不少版本，均有相应的问题，有的run起来数据通信太小，根本看不到多跳，有的压根就无法看到数据通信。
综合了一下网上的版本，修改了其中的错误，把NS2安装目录下的wireless-mitf.tcl做一下修正，分享一个可以看到多跳的基于DSR路由的模拟脚本。相信对于刚入门想做这个的人会有帮助。 脚本名字为multi-hop.tcl，生成的动画文件为multi_hop.nam。 #Copyright (c) 1997 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 Computer Systems # Engineering Group at Lawrence Berkeley Laboratory. # 4. Neither the name of the University nor of the Laboratory 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. # # $Header: /cvsroot/nsnam/ns-2/tcl/ex/wireless-mitf.tcl,v 1.2 2000/08/30 00:10:45 haoboy Exp $ # # Simple demo script for the new APIs to support multi-interface for # wireless node. # # Define options # Please note: # 1. you can still specify "channelType" in node-config right now: # set val(chan) Channel/WirelessChannel # $ns_ node-config ... # -channelType $val(chan) # ... # But we recommend you to use node-config in the way shown in this script # for your future simulations. # # 2. Because the ad-hoc routing agents do not support multiple interfaces # currently, this script can't generate anything interesting if you config # the interfaces of node 1 and 2 on different channels # # --Xuan Chen, USC/ISI, July 21, 2000 # set val(chan) Channel/WirelessChannel ;#Channel Type set val(prop) Propagation/TwoRayGround ;# radio-propagation model set val(netif) Phy/WirelessPhy ;# network interface type set val(mac) Mac/802_11 ;# MAC type # 如果用DSR，则需要用CMUPriQueue队列，否则用Queue/DropTail/PriQueue set val(ifq) CMUPriQueue ;#Queue/DropTail/PriQueue ;# interface queue type set val(ll) LL ;# link layer type set val(ant) Antenna/OmniAntenna ;# antenna model set val(ifqlen) 50 ;# max packet in ifq set val(nn) 3 ;# number of mobilenodes #set val(rp) DSDV ;# routing protocol set val(rp) DSR ;# routing protocol set val(x) 500 set val(y) 500 # Initialize Global Variables set ns_ [new Simulator] set tracefd [open multi_hop.tr w] $ns_ trace-all $tracefd set namtrace [open multi_hop.nam w] $ns_ namtrace-all-wireless $namtrace $val(x) $val(y) # set up topography object set topo [new Topography] $topo load_flatgrid $val(x) $val(y) # Create God # 这几句和下面的god set set-dist相关 # 我觉得不要手动设置最短路径也行的。 #set god [create-god $val(nn)] create-god $val(nn) # New API to config node: # 1. Create channel (or multiple-channels); # 2. Specify channel in node-config (instead of channelType); # 3. Create nodes for simulations. # Create channel #1 and #2 set chan_1_ [new $val(chan)] set chan_2_ [new $val(chan)] set chan_3_ [new $val(chan)] # Create node(0) "attached" to channel #1 # configure node, please note the change below. $ns_ node-config -adhocRouting $val(rp) / -llType $val(ll) / -macType $val(mac) / -ifqType $val(ifq) / -ifqLen $val(ifqlen) / -antType $val(ant) / -propType $val(prop) / -phyType $val(netif) / -topoInstance $topo / -agentTrace ON / -routerTrace ON / -macTrace ON / -movementTrace OFF / -channel $chan_1_ set node_(0) [$ns_ node] # node_(1) can also be created with the same configuration, or with a different # channel specified. # Uncomment below two lines will create node_(1) with a different channel. # $ns_ node-config / # -channel $chan_2_ set node_(1) [$ns_ node] set node_(2) [$ns_ node] $node_(0) random-motion 0 $node_(1) random-motion 0 $node_(2) random-motion 0 # # Provide initial (X,Y, for now Z=0) co-ordinates for mobilenodes # 设置节点的初始位置 # 注意设置节点位置的代码必须放到设置节点大小的代码前面 $node_(0) set X_ 0.0 $node_(0) set Y_ 0.0 $node_(0) set Z_ 0.0 $node_(1) set X_ 300.0 $node_(1) set Y_ 255.0 $node_(1) set Z_ 0.0 $node_(2) set X_ 100.0 $node_(2) set Y_ 100.0 $node_(2) set Z_ 0.0 # $god set set-dist 0 2 2 # $god set set-dist 0 1 1 # $god set set-dist 1 2 1 # 注意这点代码必须放到上述设置节点位置的后面 # 不然的话，初始的节点会混到一起，居然有这个bug for {set i 0} {$i < $val(nn)} {incr i} { # 设置节点的大小 $ns_ initial_node_pos $node_($i) 30 } # # Now produce some simple node movements # Node_(1) starts to move towards node_(0) # $ns_ at 3.0 "$node_(0) setdest 48.0 38.0 5.0" $ns_ at 3.0 "$node_(1) setdest 220.0 50.0 25.0" $ns_ at 3.0 "$node_(2) setdest 450.0 400.0 8.0" # Node_(1) then starts to move away from node_(0) $ns_ at 20.0 "$node_(2) setdest 490.0 480.0 30.0" # Setup traffic flow between nodes # TCP connections between node_(0) and node_(2) set tcp [new Agent/TCP] $tcp set class_ 2 set sink [new Agent/TCPSink] $ns_ attach-agent $node_(0) $tcp $ns_ attach-agent $node_(2) $sink $ns_ connect $tcp $sink set ftp [new Application/FTP] $ftp attach-agent $tcp $ns_ at 3.0 "$ftp start" # # Tell nodes when the simulation ends # for {set i 0} {$i < $val(nn) } {incr i} { $ns_ at 30.0 "$node_($i) reset"; } $ns_ at 30.0 "stop" $ns_ at 30.01 "puts /"NS EXITING.../" ; $ns_ halt" proc stop {} { global ns_ tracefd $ns_ flush-trace close $tracefd } puts "Starting Simulation..." $ns_ run 说明，上述脚本中，生成了3个无线网络节点，都处于运动状态。最后第三个节点node2跑出了node0和node1的范围。本脚本模拟了网络由一跳到二跳到最终分裂的过程。 但愿对相应需求的和我一样的初学者能少走弯路