ns3学习笔记（三）：静态路由配置

在研究路由问题的时候遇到了这个问题，小结一下            

一、路由协议栈修改

参考ns3之使用Ipv4ListRouting在一个节点上插入不同的路由协议_ipv4listroutinghelper-优快云博客
PS.
1.记得添加头文件
2.这一段代码在创建nodes、channels之后，分配ip地址之前
3. 数字越大，优先级越高

#include "ns3/ipv4-static-routing-helper.h"
#include "ns3/ipv4-list-routing-helper.h"

//   InternetStackHelper internet;
//   internet.Install (nodes);
  //安装协议栈
  Ipv4GlobalRoutingHelper globalRouting;
  Ipv4StaticRoutingHelper staticRouting;

  Ipv4ListRoutingHelper list;
  list.Add (staticRouting, 20);//设置路由优先级,优先使用静态路由协议
  list.Add (globalRouting, 10);

  InternetStackHelper internet;
  internet.SetRoutingHelper (list); 
  internet.Install (nodes);

二、分配IP地址

给静态路由涉及到的链路增加Ipv4InterfaceContainer，这样方便之后单独设置路由节点，这一段也可以省略

    //分配IP地址
  NS_LOG_INFO ("Assign IP Addresses.");
  Ipv4AddressHelper ipv4;
  ipv4.SetBase("10.1.1.0","255.255.255.0");
  ipv4.Assign(d0d1);
  Ipv4InterfaceContainer i0i1 = ipv4.Assign(d0d1);

三、 配置具体的静态路由路径

需要为每个涉及到的节点制定转发流量的方向
参考NS3 的 ipv4-static-routing-test-suite 源码分析_ns3源码-优快云博客
参数解析：AddHostRouteTo(Ipv4Address (目的节点IP地址："10.1.1.2"), Ipv4Address (下一跳节点IP地址："10.1.10.3"), 当前节点到下一跳节点的接口：1)
PS.
①节点的IP地址可以根据分配时候的参数确定，比如是"10.1.1.0"子网下的节点，就按照10.1.1.1、10.1.1.2这样按照节点次序依次分配，接口同理，可以再通过可视化模块验证下IP地址
②目的节点IP地址是默认的最小地址，就是最先分配的地址，在这里被卡了好久
③还需要给别的节点用全局路由填充路由表，不然只有这一条流会运行

  // 获取每个节点的Ipv4实例和静态路由协议实例
  // 8-5-2-3-0-1

    Ptr<Ipv4> ipv4_8 = nodes.Get(8)->GetObject<Ipv4>();
    Ptr<Ipv4StaticRouting> staticRouting_8 = staticRouting.GetStaticRouting(ipv4_8);

    // // path1:8-5-2-3-0-1
    staticRouting_8->AddHostRouteTo(Ipv4Address ("10.1.1.2"), Ipv4Address ("10.1.10.3"), 1);
    staticRouting_5->AddHostRouteTo(Ipv4Address ("10.1.1.2"), Ipv4Address ("10.1.5.1"), 1);
    staticRouting_2->AddHostRouteTo(Ipv4Address ("10.1.1.2"), Ipv4Address ("10.1.4.2"), 1);
    staticRouting_3->AddHostRouteTo(Ipv4Address ("10.1.1.2"), Ipv4Address ("10.1.2.1"), 1);
    staticRouting_0->AddHostRouteTo(Ipv4Address ("10.1.1.2"), Ipv4Address ("10.1.1.2"), 1);

    // 其余节点的路由表也要填充
    Ipv4GlobalRoutingHelper::PopulateRoutingTables ();

四、设置流量模型

这里采用的是on\off流量模型，主要参数OnTime、OffTime、DataRate、PacketSize
PS.注意发送方、接收方的定义，和UdpEchoClientHelper不太一样
1.定义监听端口port相关的是接收方
2.install流量模型的是发送方

  NS_LOG_INFO ("Create Applications.");
  uint16_t port = 9;   // Discard port (RFC 863)
  UdpEchoServerHelper echoServer (9);

  //业务1：onoff,8-1
  //接收方：InetSocketAddress
  OnOffHelper onoff ("ns3::UdpSocketFactory",
                      InetSocketAddress (i0i1.GetAddress (1), port));
  onoff.SetAttribute ("OnTime", StringValue ("ns3::ConstantRandomVariable[Constant=1]"));
  onoff.SetAttribute ("OffTime", StringValue ("ns3::ConstantRandomVariable[Constant=0]"));
  onoff.SetAttribute ("DataRate", StringValue ("1Mbps"));
  onoff.SetAttribute ("PacketSize", UintegerValue (1024));
  
  // 发送方：onoff.install\sink.install
  ApplicationContainer clientapps = onoff.Install (nodes.Get (8));
  clientapps.Start (Seconds (1.0));
  clientapps.Stop (Seconds (10.0));

  PacketSinkHelper sink ("ns3::UdpSocketFactory",
                         Address (InetSocketAddress (Ipv4Address::GetAny (), port)));
  ApplicationContainer serverapps = sink.Install (nodes.Get (8));
  serverapps.Start (Seconds (1.0));
  serverapps.Stop (Seconds (10.0));

五、输出性能指标

这里使用的是Flowmonitor，参考ns3利用FlowMonitor进行网络性能分析 - 代码先锋网
PS.
1.注意添加头文件
2.flowmonitor生成的xml和可视化的xml不一样，注意打开方式，否则NetAnim会闪退

#include "ns3/flow-monitor-module.h"
#include "ns3/flow-monitor-helper.h"

FlowMonitorHelper flowmon; 
  Ptr<FlowMonitor> monitor = flowmon.InstallAll();
  NS_LOG_INFO ("Run Simulation.");
  Simulator::Stop(Seconds(10.0));
  Simulator::Run();
  
  monitor->CheckForLostPackets();
  Ptr<Ipv4FlowClassifier> classifier = DynamicCast<Ipv4FlowClassifier>(flowmon.GetClassifier());
  FlowMonitor::FlowStatsContainer stats = monitor->GetFlowStats();
  for (auto it = stats.begin(); it != stats.end(); ++it) {
    Ipv4FlowClassifier::FiveTuple t = classifier->FindFlow(it->first);
    std::cout << "Flow ID: " << it->first << " Source IP: " << t.sourceAddress << " Destination IP: " << t.destinationAddress << std::endl;
    std::cout << "  Tx Packets: " << it->second.txPackets << " Rx Packets: " << it->second.rxPackets << std::endl;
    // std::cout << "  Lost Packets: " << it->second.lostPackets << std::endl;
    std::cout << "  Lost Packets: " << it->second.txPackets-it->second.rxPackets << std::endl;
    std::cout << "  Delay (s): " << it->second.delaySum.GetSeconds() << std::endl;
    std::cout << "  Jitter (s): " << it->second.jitterSum.GetSeconds() << std::endl;
    std::cout << "  Throughput (bps): " << it->second.rxBytes * 8.0 / 10.0 << std::endl;  // 除以仿真时长得到平均吞吐量
    }

  //flowmonitor生成的xml和可视化的不一样，注意打开方式
  monitor->SerializeToXmlFile("demo6.xml", true, true);

   可视化仿真结果如下：

  Flow-monitor读取xml结果如下：