NS网络模拟和协议仿真源代码VIP专享

第 4 章例 1＃建立一个模拟set ns ［new Simulator］＃定义不同数据流的颜色（NAM显示时用到)$ns color 1 Blue$ns color 2 Red＃开启Trace跟踪和NAM跟踪set tracefd [open wired.tr w］＄ns trace-all $tracefdset nf [open wired。nam w]＄ns namtrace—all ＄nf#定义结束进程proc finish ｛} {global ns tracefd nf$ns flush-traceclose $tracefdclose ＄nfexit 0}＃定义节点set n0 ［$ns node]set n1 ［＄ns node]set n2 [$ns node］set n3 ［$ns node］set n4 ［＄ns node］set n5 ［＄ns node]＃＄n5 color black＄n5 color red#定义节点间的链路$ns duplex-link $n0 $n1 2Mb 10ms DropTail$ns duplex-link $n1 ＄n2 2Mb 10ms DropTail$ns duplex-link $n1 ＄n4 2Mb 20ms DropTail$ns duplex-link ＄n3 ＄n4 2Mb 10ms DropTail$ns duplex—link $n4 $n5 2Mb 10ms DropTail＃定义链路的队列长度$ns queue-limit $n1 ＄n4 10#指定节点间的相互位置（NAM显示用到)$ns duplex-link-op ＄n0 ＄n1 orient right—down＄ns duplex-link-op $n2 ＄n1 orient right-up＄ns duplex—link-op $n1 $n4 orient right＄ns duplex-link-op $n3 ＄n4 orient left-down＄ns duplex-link-op ＄n5 ＄n4 orient left—up＃监视链路的队列＄ns duplex—link-op $n1 $n4 queuePos 0。5＃建立一个TCP连接set tcp [new Agent/TCP］ ＄tcp set class_ 2$ns attach-agent $n0 $tcpset sink [new Agent/TCPSink]$ns attach-agent $n5 ＄sink＄ns connect ＄tcp ＄sink$tcp set fid_ 1＃在TCP连接上建立FTP流set ftp ［new Application/FTP］$ftp attach—agent $tcp＄ftp set type_ FTP＃建立一个UDP代理set udp ［new Agent/UDP] ;＃建立一个数据发送代理＄ns attach—agent $n2 ＄udp ;#将数据发送代理绑定到发送节点set null ［new Agent/Null] ;#建立一个数据接收代理$ns attach-agent ＄n3 ＄null ；#将数据接收代理绑定到接收节点$ns connect $udp ＄null ；＃连接两个代理(也就决定了数据包的发送和接收节点）＄udp set fid_ 2#在UDP代理上建立CBR流set cbr ［new Application/Traffic/CBR］$cbr attach—agent ＄udp＄cbr set type_ CBR$cbr set packet_size_ 1000$...