運用ns-3模擬數據中心〔datacenter〕試驗報告一.試驗工具Ubuntu、Vmware虛擬機、ns-3仿真器、Wireshark抓包工具二.試驗步驟1.編寫程序模擬網絡拓撲及網絡消息傳輸狀態〔多對一和多對多〕2.Wireshark抓包工具對輸出的.pcap文件進展分析3.試驗總結三.網絡拓撲圖〔1〕四.重要代碼解釋//備注：以下是實現主機間多對一通信的代碼，其中多指的為主機h2—h8，一為主機//h1.//庫函數調用#include“ns3/core-module.h“#include“ns3/network-module.h“#include“ns3/csma-module.h“#include“ns3/internet-module.h“#include“ns3/applications-module.h“#include“ns3/ipv4-global-routing-helper.h“usingnamespacens3;NS_LOG_COMPONENT_DEFINE(“SecondScriptExample“);intmain(intargc,char*argv[]){boolverbose=true;uint32_tnCsma=3;uint32_tnFlows=7;uint16_tport=5000;CommandLinecmd;//cmd.AddValue(“nCsma“,“Numberof\“extra\“CSMAnodes/devices“,nCsma);cmd.AddValue(“verbose“,“Tellechoapplicationstologiftrue“,verbose);cmd.Parse(argc,argv);if(verbose)//為真{////LOG模塊,LOG消息LogComponentEnable(“PacketSink“,LOG_LEVEL_INFO);LogComponentEnable(“OnOffApplication“,LOG_LEVEL_INFO);}nCsma=nCsma==0?1:nCsma;4csma網絡NodeContainercsmaNodes1;csmaNodes1.Create(3);NodeContainercsmaNodes2;csmaNodes2.Create(3);NodeContainercsmaNodes3;csmaNodes3.Create(3);NodeContainercsmaNodes4;csmaNodes4.Create(3);csma中左側網絡NodeContainercsmaNodes5;csmaNodes5.Create(1);csmaNodes5.Add(csmaNodes1.Get(0));csmaNodes5.Add(csmaNodes2.Get(0));csma中右側網絡NodeContainercsmaNodes6;csmaNodes6.Create(1);csmaNodes6.Add(csmaNodes3.Get(0));csmaNodes6.Add(csmaNodes4.Get(0));//csmacsma網絡NodeContainercsmaNodes7;csmaNodes7.Create(1);csmaNodes7.Add(csmaNodes5.Get(0));csmaNodes7.Add(csmaNodes6.Get(0));//CMSA1網絡拓撲CsmaHelpercsma1;csma1.SetChannelAttribute(“DataRate“,StringValue(“1.0Mbps“));csma1.SetChannelAttribute(“Delay“,TimeValue(NanoSeconds(500)));NetDeviceContainercsmaDevices1;csmaDevices1=csma1.Install(csmaNodes1);//CMSA2網絡拓撲CsmaHelpercsma2;csma2.SetChannelAttribute(“DataRate“,StringValue(“1.0Mbps“));csma2.SetChannelAttribute(“Delay“,TimeValue(NanoSeconds(500)));NetDeviceContainercsmaDevices2;csmaDevices2=csma2.Install(csmaNodes2);//CMSA3網絡拓撲CsmaHelpercsma3;csma3.SetChannelAttribute(“DataRate“,StringValue(“1.0Mbps“));csma3.SetChannelAttribute(“Delay“,TimeValue(NanoSeconds(500)));NetDeviceContainercsmaDevices3;csmaDevices3=csma3.Install(csmaNodes3);//CMSA4網絡拓撲CsmaHelpercsma4;csma4.SetChannelAttribute(“DataRate“,StringValue(“1.0Mbps“));csma4.SetChannelAttribute(“Delay“,TimeValue(NanoSeconds(500)));NetDeviceContainercsmaDevices4;csmaDevices4=csma4.Install(csmaNodes4);//CMSA5網絡拓撲CsmaHelpercsma5;csma5.SetChannelAttribute(“DataRate“,StringValue(“1.0Mbps“));csma5.SetChannelAttribute(“Delay“,TimeValue(NanoSeconds(500)));NetDeviceContainercsmaDevices5;csmaDevices5=csma5.Install(csmaNodes5);//CMSA6網絡拓撲CsmaHelpercsma6;csma6.SetChannelAttribute(“DataRate“,StringValue(“1.0Mbps“));csma6.SetChannelAttribute(“Delay“,TimeValue(NanoSeconds(500)));NetDeviceContainercsmaDevices6;csmaDevices6=csma6.Install(csmaNodes6);//CMSA7網絡拓撲CsmaHelpercsma7;csma7.SetChannelAttribute(“DataRate“,StringValue(“1.5Mbps“));csma7.SetChannelAttribute(“Delay“,TimeValue(NanoSeconds(500)));NetDeviceContainercsmaDevices7;csmaDevices7=csma7.Install(csmaNodes7);//安裝協議棧〔node只有一個stack〕InternetStackHelperstack;stack.Install(csmaNodes1);stack.Install(csmaNodes2);stack.Install(csmaNodes3);stack.Install(csmaNodes4);stack.Install(csmaNodes5.Get(0));stack.Install(csmaNodes6.Get(0));stack.Install(csmaNodes7.Get(0));node0：10.1.1.1；node1：10.1.1.2Ipv4AddressHelperaddress;//CSMA1t1IP10.0.1.1n1IP為10.0.1.2IP10.0.1.3address.SetBase(“10.0.1.0“,“255.255.255.0“);Ipv4InterfaceContainercsmaInterfaces1;csmaInterfaces1=address.Assign(csmaDevices1);//CSMA2CSMA1IP安排address.SetBase(“10.0.2.0““255.255.255.0“);Ipv4InterfaceContainercsmaInterfaces2;csmaInterfaces2=address.Assign(csmaDevices2);//CSMA3CSMA1IP安排address.SetBase(“10.0.3.0““255.255.255.0“);Ipv4InterfaceContainercsmaInterfaces3;csmaInterfaces3=address.Assign(csmaDevices3);//CSMA4CSMA1IP安排address.SetBase(“10.0.4.0““255.255.255.0“);Ipv4InterfaceContainercsmaInterfaces4;csmaInterfaces4=address.Assign(csmaDevices4);//CSMA5a1IP10.1.1.1t1上端口IP10.1.1.2//t2IP10.1.1.3address.SetBase(“10.1.1.0“,“255.255.255.0“);Ipv4InterfaceContainercsmaInterfaces5;csmaInterfaces5=address.Assign(csmaDevices5);//CSMA6CSMA5IP安排address.SetBase(“10.2.1.0““255.255.255.0“);Ipv4InterfaceContainercsmaInterfaces6;csmaInterfaces6=address.Assign(csmaDevices6);//CSMA7c1IP192.168.1.1a1上端口IP192.168.1.2IP192.168.1.3address.SetBase(“192.168.1.0“,“255.255.255.0“);Ipv4InterfaceContainercsmaInterfaces7;csmaInterfaces7=address.Assign(csmaDevices7);//h27個不同的端口，5000-5006ApplicationContainersinkApp[nFlows];for(unsignedinti=0;i<nFlows;i++){PacketSinkHelperpacketSinkHelper(“ns3::TcpSocketFactory“,InetSocketAddress(csmaInterfaces1.GetAddress(1),port+i));sinkApp[nFlows]=packetSinkHelper1.Install(csmaNodes1.Get(1));sinkApp[nFlows].Start(Seconds(1.0));sinkApp[nFlows].Stop(Seconds(60.0));}h2作為clienth3-h8client的代碼類似：ApplicationContainerclientApp2;OnOffHelperclient2(“ns3::TcpSocketFactory“,InetSocketAddress(csmaInterfaces1.GetAddress(1),5000));client2.SetAttribute(“OnTime“,StringValue(“ns3::ConstantRandomVariable[Constant=50]“));client2.SetAttribute(“OffTime“,StringValue(“ns3::ConstantRandomVariable[Constant=0]“));client2.SetAttribute(“DataRate“,DataRateValue(DataRate(“1.5Mbps“)));client2.SetAttribute(“PacketSize“,UintegerValue(2000));clientApp2=client2.Install(csmaNodes1.Get(2));clientApp2.Start(Seconds(2));clientApp2.Stop(Seconds(50));Ipv4GlobalRoutingHelper::PopulateRoutingTables;//tracing消息，執行仿真csma1.EnablePcap(“dc1“,csmaDevices1.Get(1),true);Simulator::Run;Simulator::Destroy;return0;}五.多對一試驗仿真結果Wireshark對試驗輸出的.pcaph1的端口。上述程序輸出的文件名為：dc1-1-0.pcap。TCP回話，如圖〔2〕所示：圖〔2〕圖〔2〕1tcpflowFilter中輸入字符串tcp.srcport==5000||tcp.dstport==5000，條件篩選如圖〔3〕所示：圖〔3〕5000throughputh2h1的通信。如圖〔4〕所示：圖〔圖〔4〕5000rtth2h1的通信。如圖〔5〕所示：5001throughputh3h1的通信。如圖〔6〕所示：圖〔5〕5001rtth3h1的通信。如圖〔7〕所示：5002throughputh4h1的通信。如圖〔8〕所示：50035003throughputh5h1的通信。如圖〔10〕所示：圖〔6〕第三個端口5002的rtt，即h4與h1的通信。如圖〔9〕所示：5003rtth5h1的通信。如圖〔10〕所示：5004throughputh6h1的通信。如圖〔11〕所示：50055005throughputh7h1的通信。如圖〔13〕所示：第五個端口5004的rtt，即h6與h1的通信。如圖〔12〕所示：5005rtth7h1的通信。如圖〔14〕所示：5006throughputh8h1的通信。如圖〔15〕所示：5006rtth8h1的通信。如圖〔16〕所示：試驗結果分析：從圖〔4〕—圖〔10〕可以看出，當多個主機向一個主機發送數據包時〔在試驗中是其h1發送數據包〕。CSMAh1h2rtt也趨于h2h1rtt有一個峰值，這是說明在t1rtt有峰值。h3h4h1的通信過程。由于h3h4t2進展數據包的轉發，所以，h3吞吐量的峰值h4吞吐量的低谷，h3h4吞吐量的峰值。h5，h6，h7h8h1進展通信時，在時間<40s時，吞吐量很低。造成這一現象的緣由有兩種：①這些主機需要多跳才能傳給目的主機②通信前半時間，這些主機的數據包處于路由排隊的對尾。六.多對多重點試驗代碼解釋由于多數代碼與多對一一樣，在這里僅解釋不同之處。//zhujih1--->h5ApplicationContainerclientApp1;OnOffHelperclient1(“ns3::TcpSocketFactory“,InetSocketAddress(csmaInterfaces3.GetAddress(1),5000));client1.SetAttribute(“OnTime“,StringValue(“ns3::ConstantRandomVariable[Constant=50]“));client1.SetAttribute(“OffTime“,StringValue(“ns3::ConstantRandomVariable[Constant=0]“));client1.SetAttribute(“DataRate“,DataRateValue(DataRate(“1.5Mbps“)));client1.SetAttribute(“PacketSize“,UintegerValue(2000));clientApp1=client1.Install(csmaNodes1.Get(1));clientApp1.Start(Seconds(2));clientApp1.Stop(Seconds(50));h1h5h6h