NS-3学习之aodv.cc 变种

/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2009 IITP RAS
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation;
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * This is an example script for AODV manet routing protocol. 
 *
 * Authors: Pavel Boyko <boyko@iitp.ru>
 */

#include <iostream>
#include <cmath>
#include "ns3/aodv-module.h"
#include "ns3/core-module.h"
#include "ns3/network-module.h"
#include "ns3/internet-module.h"
#include "ns3/mobility-module.h"
#include "ns3/point-to-point-module.h"
#include "ns3/v4ping-helper.h"
#include "ns3/yans-wifi-helper.h"

using namespace ns3;

/**
 * \ingroup aodv-examples
 * \ingroup examples
 * \brief Test script.
 * 
 * This script creates 1-dimensional grid topology and then ping last node from the first one: 创建一维的网络拓扑，第一个节点ping最后一个节点
 * 
 * [10.0.0.1] <-- step --> [10.0.0.2] <-- step --> [10.0.0.3] <-- step --> [10.0.0.4]
 * 
 * ping 10.0.0.4
 *
 * When 1/3 of simulation time has elapsed, one of the nodes is moved out of
 * range, thereby breaking the topology.  By default, this will result in
 * only 34 of 100 pings being received.  If the step size is reduced
 * to cover the gap, then all pings can be received.
 * 当经过1/3的模拟时间后，其中一个节点被移出范围，从而破坏拓扑
 * 默认情况下，这将导致100个ping中只有34个被接收。
 * 如果减小步长以覆盖间隙，那么所有的ping都能被接收
 */
class AodvExample {
public:
	AodvExample();
	/**
	 * \brief Configure script parameters
	 * \param argc is the command line argument count
	 * \param argv is the command line arguments
	 * \return true on successful configuration
	 */
	bool Configure(int argc, char **argv);
	/// Run simulation
	void Run();
	/**
	 * Report results
	 * \param os the output stream
	 */
	void Report(std::ostream &os);

private:

	// parameters
	/// Number of nodes
	uint32_t size;
	/// Distance between nodes, meters 节点间隔，单位:米
	double step;
	/// Simulation time, seconds
	double totalTime;
	/// Write per-device PCAP traces if true 如果pcap 设置为true，则每个节点生成一个pcap 文件
	bool pcap;
	/// Print routes if true
	bool printRoutes;

	// network
	/// nodes used in the example
	NodeContainer nodes;
	/// devices used in the example
	NetDeviceContainer devices;
	/// interfaces used in the example
	Ipv4InterfaceContainer interfaces;

private:
	/// Create the nodes
	void CreateNodes();
	/// Create the devices
	void CreateDevices();
	/// Create the network
	void InstallInternetStack();
	/// Create the simulation applications
	void InstallApplications();
};

int main(int argc, char **argv) {
	AodvExample test;
	if (!test.Configure(argc, argv))
		NS_FATAL_ERROR("Configuration failed. Aborted.");

	test.Run();
	test.Report(std::cout);
	return 0;
}

//-----------------------------------------------------------------------------
AodvExample::AodvExample() :
		size(12), step(50), totalTime(10), pcap(true), printRoutes(true) {
}

bool AodvExample::Configure(int argc, char **argv) {
	// Enable AODV logs by default. Comment this if too noisy
	// LogComponentEnable("AodvRoutingProtocol", LOG_LEVEL_ALL);

	SeedManager::SetSeed(12345);
	CommandLine cmd(__FILE__);

	cmd.AddValue("pcap", "Write PCAP traces.", pcap);
	cmd.AddValue("printRoutes", "Print routing table dumps.", printRoutes);
	cmd.AddValue("size", "Number of nodes.", size);
	cmd.AddValue("time", "Simulation time, s.", totalTime);
	cmd.AddValue("step", "Grid step, m", step);

	cmd.Parse(argc, argv);
	return true;
}

void AodvExample::Run() {
//  Config::SetDefault ("ns3::WifiRemoteStationManager::RtsCtsThreshold", UintegerValue (1)); // enable rts cts all the time.
	CreateNodes();	//创建节点并为节点分配初始位置和移动模型
	CreateDevices();	//为节点安装wifi网络设备，包括设置信道，设置物理层协，设置Mac 层
	InstallInternetStack();	//为节点安装协议栈，为网络设备分配IP地址
	InstallApplications();	//为第一个节点安装ping 应用，ping 最后一个节点

	std::cout << "Starting simulation for " << totalTime << " s ...\n";

	Simulator::Stop(Seconds(totalTime));
	Simulator::Run();
	Simulator::Destroy();
}

void AodvExample::Report(std::ostream&) {
}

//Jerry:创建节点并为节点分配初始位置和移动模型
void AodvExample::CreateNodes() {
	std::cout << "Creating " << (unsigned) size << " nodes " << step
			<< " m apart.\n";
	nodes.Create(size);
	// Name nodes，命名节点
	for (uint32_t i = 0; i < size; ++i) {
		std::ostringstream os;
		os << "node-" << i;
		Names::Add(os.str(), nodes.Get(i));
	}
	// Create static grid
	/*
	 * (58条消息) ns-3 GridPositionAllocator 属性解释_ns-3网络模拟，ns3路由协议仿真-优快云博客
	 * https://blog.youkuaiyun.com/barcodegun/article/details/6981475
	 */
	MobilityHelper mobility;
	//设置位置分配器
	mobility.SetPositionAllocator("ns3::GridPositionAllocator", "MinX",
			DoubleValue(0.0), "MinY", DoubleValue(0.0), "DeltaX",
			DoubleValue(step), "DeltaY", DoubleValue(step), "GridWidth",
			UintegerValue(3), "LayoutType", StringValue("RowFirst"));
	//设置移动模型
//	mobility.SetMobilityModel("ns3::ConstantPositionMobilityModel");
	mobility.SetMobilityModel("ns3::RandomWalk2dMobilityModel", "Bounds",
			RectangleValue(Rectangle(-5000, 5000, -5000, 5000)));
	mobility.Install(nodes);
}

//为节点安装wifi网络设备，包括设置信道，设置物理层协，设置Mac 层
void AodvExample::CreateDevices() {
	//设置wifi 协议的mac 层
	WifiMacHelper wifiMac;
	wifiMac.SetType("ns3::AdhocWifiMac");

	YansWifiPhyHelper wifiPhy;	//Wifi 协议的物理层实现
	YansWifiChannelHelper wifiChannel = YansWifiChannelHelper::Default();//用来创建拥有默认PropagationLoss和PropagationDelay模型的WifiChannel
	wifiPhy.SetChannel(wifiChannel.Create());

	WifiHelper wifi;
	wifi.SetRemoteStationManager("ns3::ConstantRateWifiManager", "DataMode",
			StringValue("OfdmRate6Mbps"), "RtsCtsThreshold", UintegerValue(0));	//RemoteStationManager：速率控制（rate control），根据网络环境选择最佳数据速率（data rate）。
	devices = wifi.Install(wifiPhy, wifiMac, nodes);//将物理和Mac层设备安装到节点上并返回设备列表。

	if (pcap) {
		wifiPhy.EnablePcapAll(std::string("aodv"));	//设置前缀名。命名规则是“前缀名-<结点标号>-<网络设备标号>”
	}
}

//为节点安装协议栈，为网络设备分配IP地址
void AodvExample::InstallInternetStack() {
	AodvHelper aodv;
	// you can configure AODV attributes here using aodv.Set(name, value)
	InternetStackHelper stack;
	stack.SetRoutingHelper(aodv); // has effect on the next Install ()
	stack.Install(nodes);
	Ipv4AddressHelper address;
	address.SetBase("10.0.0.0", "255.0.0.0"); //起始主机号默认值为0.0.0.1,address.Assign()函数会按照索引次序为容器devices中的NetDevice对象依次分配地址
	interfaces = address.Assign(devices); //为设备分配网络地址，而不是为节点分配

	if (printRoutes) {
		Ptr<OutputStreamWrapper> routingStream = Create<OutputStreamWrapper>(
				"aodv.routes", std::ios::out);
		aodv.PrintRoutingTableAllAt(Seconds(8), routingStream);
	}
}

//为第一个节点安装ping 应用，ping 最后一个节点
void AodvExample::InstallApplications() {
	V4PingHelper ping(interfaces.GetAddress(size - 1)); //ping 最后一个节点
	ping.SetAttribute("Verbose", BooleanValue(true)); //verbose方式，它要ping命令除了打印ECHO-RESPONSE数据包之外，还打印其它所有返回的ICMP数据包。

	ApplicationContainer p = ping.Install(nodes.Get(0));
	p.Start(Seconds(0));
	p.Stop(Seconds(totalTime) - Seconds(0.001));

	// move node away 移开节点
	Ptr<Node> node = nodes.Get(size / 2);
	Ptr<MobilityModel> mob = node->GetObject<MobilityModel>();
	Simulator::Schedule(Seconds(totalTime / 3), &MobilityModel::SetPosition,
			mob, Vector(-80, -10, 0));
}

代码参考自NS-3 3.35 官方src/aodv/aodv.cc，原来的源码是产生10个节点，节点排成一行，节点位置固定，节点间距50米，运行1/3 总仿真时间后将排在中间的一个节点移开。

我修改之后的代码是12个节点，每行3个，排成4行，节点位置是随时间随机移动的，同样运行1/3总仿真时间后将节点号排在中间的节点移动到Vector（-80，-10，0）的位置上。修改的主要目的很简单，就是想看看下节点排成多排，随机移动，节点按坐标点移动等运行效果。