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网络ns2仿真实验分析(RED、丢包率、端到端延迟、吞吐量)附源码分组的端口号。(10) dst addr:目的地址,格式为 node port,其中node代表分组发送节点的id,pot表示发送分组的端口号。(11) seg num:分组的序列号。(12) okt id:分组的唯标识符。3n2与n3之间的RED队列的半均队列长度与当前队列长度随时间的变化如下图所示:torrent and ave"吧 e PED CueL旧300era已n15000ANA图2平均队列长度与当前队列长度随时问变化的曲线图4运行结果中显示CBR流量总共发包550,丢失16,丢包率为:0.029。丢包率随时间的变化如下图所示:packets of lost rate。045graph自04,03500自020.015图3丢包率随时间变化的关系图5CBR流量的吋延随时间的变化如下图所示:1u彐r10.14心01Q。0图4端到端时延随时间变化的关系图6.节点n2的平均吞吐量随时间的变化如下图所示100T图5节点n2的吞吐量随时间变化的关系头7.结果分析:从RED的图示中,可以看出队列的大小波动变化不是很大,在处理突发的包时冇一定的优势。从丟包率、时延和吞吐量的变化图中,可以看出当丟包率增加时,端到端之问的时延也在增加,而吞吐量则下降,丟包率、时延和吞吐量在表示网络性能的好坏时有一定的关系、相关代码1.络拓扑仿真脚木 simulator:tcl:#Create a simulator objectset ns [new Simulator]#Define different colors for data flows for NAM)Sns color 1 BlueSns color 2#Open the nam trace fileset nt lopen out. nam wSns namtrace-all Snfset nd [open out. tr wISns trace-all Snd#Define a finish procedureproc finish仆}{global ns nf ndSns flush-traceclose Snfclose sndexec nam out. namkit o#Create four nodesset no [Sns node]et n1 [Sns nodelset n2 [Sns nodeset n3 [ns node]#Create links between the nodesSns duplex-link Sn0 Sn2 2Mb 10ms DropTailSns duplex-link Sn1 Sn2 2Mb 10ms DropTailSns duplex- link Sn2 Sn3 1.7Mb 20ms RED#Set queue Size of link (n2-n3 to 100Sns queue-limit Sn2 Sn 3 100#Give node position(for NAm)Sns duplex-link-op SnO Sn2 orient right-downSns duplex-link-op Sn1 Sn2 orient right-upSns duplex-link-op $n2 Sn3 orient right#Monitor the queue for link(n2-n3 .( for NAM)Sns duplex-link-op Sn2 Sn 3 queuePos 0.5#Setup a TCP connectionset tcp new Agent/TCPISns attach-agent Sno Stcpset sink [new Agent/TCPSinkSns attach-agent sn3 SinkSns connect stcp SinkStcp set fid 1#Setup a FTP over TCP connectionset ftp [new Application/FTPlSftp attach-agent StcpSftp set type FTPfsetup a UdP connectionset udp [new Agent/UDP]Sns attach-agent Sn1 udpset null [new Agent/Nul]Sns attach-agent Sn3 SnullSns connect Udp SnullUdp set fid_ 2#Setup a CBr over UDP connectionset cbr [new application/Traffic/ CBRIScbr attach-agent UdpScbr set type CBrScbr set packet size 1000Scbr set rate 1mbScbr set random false#Schedule events for the cbr and ftp agentsSns at0.1 Scbr startSns at 1.0"Sftp start"Sns at 40.0"Sftp stop"Sns at 4.5"Scbr stop"#Detach tcp and sink agentsSns at 50 Sns detach-agent $no stcp; Sns detach-agent sn3 Sink"Sns at 50.0 finish#monitor n2 and n3 queueset redg [[sns link Sn2 Sn3] queueset traceq lopen redQueue tr wSredg trace curgSredg trace aveSredg attach Strace#Run the simulationns rur2.RED的数据处理脚本:SgreparedQueue. tr>averagetrStrep“Q" reqUeuetr> current tr(中 reqUeue tr为跟踪n2和n3队列产生的文件)然后使用 gnuplot工具使用 average tr和 current, tr绘制队列随时间变化的曲线3.丢包率数据awk处理脚本 graph rostRate,awvk#count the packet lost rate of cBri=0;vente=S2;from Node =$3toNode=s4:pitT$7srcAddr=$9dstAddr=$10gNum = $11if (fromNode ==1 & toNode ==2&& event==+i totalNum++timeArr[i=timesrate[i]= float)(drop Num/tif(fid==2&& event==d")dropNum++ENDprintf("#number of packet sent: %od, lost: %d"totalNum, dropNum)printf( #lost rate of packets: %f",dropNum/totalNumfor(j=0; j