NS3网络仿真
- NS3安装与配置
- 点对点通信
- 交换机（ARP协议）
- 其他分析文件
1. 安装与配置
参考网址：维基百科NS3配置
1.1预先安装环境
- apt-get install gcc g++ python
- apt-get install gcc g++ python python-dev
- apt-get install mercurial python-setuptools git
- apt-get install qt4-dev-tools libqt4-dev
- apt-get install cmake libc6-dev libc6-dev-i386 g++-multilib
- apt-get install gdb valgrind
- apt-get install gsl-bin libgsl2 libgsl-dev
- apt-get install flex bison libfl-dev
- apt-get install tcpdump
- apt-get install sqlite sqlite3 libsqlite3-dev
- apt-get install libxml2 libxml2-dev
- apt-get install libgtk2.0-0 libgtk2.0-dev
- apt-get install vtun lxc
- apt-get install uncrustify
- apt-get install doxygen graphviz imagemagick
- apt-get install texlive texlive-extra-utils texlive-latex-extra texlive-font-utils texlive-lang-portuguese dvipng
- apt-get install python-sphinx dia
- apt-get install python-pygraphviz python-kiwi python-pygoocanvas libgoocanvas-dev ipython
- apt-get install libboost-signals-dev libboost-filesystem-dev
- apt-get install openmpi-bin openmpi-common openmpi-doc libopenmpi-dev
1.2下载ns-3
cd
mkdir repos
cd repos
hg clone http://code.nsnam.org/ns-3-allinone
当执行完以上命令后，你会看到如下内容
destination directory: ns-3-allinone
requesting all changes
adding changesets
adding manifests
adding file changes
added 26 changesets with 40 changes to 7 files
7 files updated, 0 files merged, 0 files removed, 0 files unresolved执行结束后可以在repos目录下看到ns-3-allinone目录，该目录下包含下面文件：
build.py* constants.py dist.py* download.py* README util.py进入该目录，执行如下命令：
- ./download.py -n ns-3-dev
执行结束后，可以看到目录下多了一些文件：
build.py* constants.pyc download.py* nsc/ README util.pyc constants.py dist.py* ns-3-dev/ pybindgen/ util.py进入ns-3-dev目录，准备build ns-3。
1.3编译ns-3
- cd ns-3-dev
- ./build.py
执行期间会有大量编译信息，最后提示build finished successfully.
进入ns-3-dev目录使用waf构建
- ./waf -d optimized configure
- ./waf -d debug configure
- ./waf
- ./waf -d debug –enable-sudo configure
1.4.测试用例
首先在ns-3-dev/examples/tutorial/下找到 myfirst.cc文件，将他拷贝到到scratch目录下。
然后再返回ns-3-dev目录，执行如下命令：
- ./waf –run myfirst
1.5安装netanim
- cd netanim
- make clean
- qmake NetAnim.pro
- make
1.6测试
在myfirst.cc文件中添加头文件
#include “ns3/netanim-module.h”并在Simulartor::run()这句代码之前添加如下语句：
AnimationInterface anim(“myfirst.xml”); 保存后运行，
- ./waf – run myfirst
可以发现有myfirst.xml文件生成。
接下来进入netanim文件夹下，运行netanim
- ./NetAnim
然后选择刚才生成的myfirst.xml文件，点击运行即可。
2. 点对点通信
2.1网络拓扑
2.2源程序分析
int main (int argc, char *argv[])
{
//设置时间单位
Time::SetResolution (Time::NS);
//两个日志组件生效，并且日志级别设置为INFO
LogComponentEnable ("UdpEchoClientApplication", LOG_LEVEL_INFO);
LogComponentEnable ("UdpEchoServerApplication", LOG_LEVEL_INFO);
//声明一个结电容器并创建两个节点
NodeContainer nodes;
nodes.Create (2);
//设置点到点协议的延迟和数据速率
PointToPointHelper pointToPoint;
pointToPoint.SetDeviceAttribute ("DataRate", StringValue ("500bps"));
pointToPoint.SetChannelAttribute ("Delay", StringValue ("2ms"));
//安装点到点网络设备
NetDeviceContainer devices;
devices = pointToPoint.Install (nodes);
//安装协议栈
InternetStackHelper stack;
stack.Install (nodes);
//设置IP地址
Ipv4AddressHelper address;
address.SetBase ("10.1.1.0", "255.255.255.0");
Ipv4InterfaceContainer interfaces = address.Assign (devices);
//应用程序部分，设置udp回显服务应用
UdpEchoServerHelper echoServer (9);
//服务器端应用开始
ApplicationContainer serverApps = echoServer.Install (nodes.Get (1));
//设置服务开始和结束时间
serverApps.Start (Seconds (1.0));
serverApps.Stop (Seconds (10.0));
UdpEchoClientHelper echoClient (interfaces.GetAddress (1), 9);
echoClient.SetAttribute ("MaxPackets", UintegerValue (1));
echoClient.SetAttribute ("Interval", TimeValue (Seconds (1.0)));
echoClient.SetAttribute ("PacketSize", UintegerValue (1024));
//客户端应用开始
ApplicationContainer clientApps = echoClient.Install (nodes.Get (0));
clientApps.Start (Seconds (2.0));
clientApps.Stop (Seconds (10.0));
//产生动画
AnimationInterface anim("myFirst.xml");
//开始模拟
Simulator::Run ();
//模拟结束
Simulator::Destroy ();
return 0;
}
2.3执行结果
3.交换机（ARP协议仿真）
3.1网络拓扑
3.2实验解释
发送数据，从n0到n1。
3.3源代码分析
int main (int argc, char *argv[])
{
// 创建四个节点
NodeContainer terminals;
terminals.Create (4);
//创建网桥
NodeContainer csmaSwitch;
csmaSwitch.Create (1);
//建立拓扑结构
//设置延迟和比特率
CsmaHelper csma;
csma.SetChannelAttribute ("DataRate", DataRateValue (5000000));
csma.SetChannelAttribute ("Delay", TimeValue (MilliSeconds (2)));
// 设置链路，将各节点连接到网桥
NetDeviceContainer terminalDevices;
NetDeviceContainer switchDevices;
for (int i = 0; i < 4; i++)
{
NetDeviceContainer link = csma.Install (NodeContainer (terminals.Get (i), csmaSwitch));
terminalDevices.Add (link.Get (0));
switchDevices.Add (link.Get (1));
}
//创建网桥设备
Ptr switchNode = csmaSwitch.Get (0);
BridgeHelper bridge;
bridge.Install (switchNode, switchDevices);
// 安装协议栈
InternetStackHelper internet;
internet.Install (terminals);
// 设置IP地址
//
NS_LOG_INFO ("Assign IP Addresses.");
Ipv4AddressHelper ipv4;
ipv4.SetBase ("10.1.1.0", "255.255.255.0");
ipv4.Assign (terminalDevices);
//
// 创建ONoff应用基于udp
//
NS_LOG_INFO ("Create Applications.");
uint16_t port = 9; // Discard port (RFC 863)
OnOffHelper onoff ("ns3::UdpSocketFactory",
Address (InetSocketAddress (Ipv4Address ("10.1.1.2"), port)));
onoff.SetConstantRate (DataRate ("500kb/s"));
ApplicationContainer app = onoff.Install (terminals.Get (0));
// 设置开始应用的时间
app.Start (Seconds (1.0));
app.Stop (Seconds (10.0));
// 设置接收的节点
PacketSinkHelper sink ("ns3::UdpSocketFactory",
Address (InetSocketAddress (Ipv4Address::GetAny (), port)));
app = sink.Install (terminals.Get (1));
app.Start (Seconds (0.0));
// 记录日志
AsciiTraceHelper ascii;
csma.EnableAsciiAll (ascii.CreateFileStream ("csma-bridge.tr"));
// 创建每个节点的端口发送接收包的情况
csma.EnablePcapAll ("csma-bridge", false);
// 产生动画，用于NetAnim
AnimationInterface anim("csma-bridge.xml");
//开始模拟
Simulator::Run ();
Simulator::Destroy ();
}
3.4实验结果
第一次发送时，网桥不知道发送给哪个端口，所以进行广播；
之后地址表建立，便不再进行广播。
4.其他分析文件
4.1Pcap文件
Wireshark:可以看到每个结点接收发送数据的信息：
4.2 tr 跟踪文件
每一笔记录的开始字段都是封包事件发生的原因：
r表示这个封包被某个节点接受，+表示进入队列，-表示离开队列，d表示封包被队列丢弃；