NS初学-first.cc

在ubuntu上安装了ns3后开始使用样例学习使用ns3，ns3使用c++编程还是让我学起来比较爽的

/* NS3关键的抽象概念
 节点、应用程序、信道、网络设备、拓扑生成器
*/
/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
// 表明NS3代码风格
/*

* 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

*/

#include "ns3/core-module.h"

#include "ns3/network-module.h"

#include "ns3/internet-module.h"

#include "ns3/point-to-point-module.h"

#include "ns3/applications-module.h"//C++标准格式 这些模块头文件里更加详细的头文件

using namespace ns3;//ns3命名空间 类似于std

NS_LOG_COMPONENT_DEFINE ("FirstScriptExample");//声明了一个叫FirstScriptExample的日志构件

int

main (int argc, char *argv[])

{

Time::SetResolution (Time::NS);//设置仿真时间分辨率

LogComponentEnable ("UdpEchoClientApplication", LOG_LEVEL_INFO);

LogComponentEnable ("UdpEchoServerApplication", LOG_LEVEL_INFO);//设置这两个组件生效并设置回显clients和server的日志级别为”INFO”级

//使用生成器对象来帮助配置和管理潜在的对象
NodeContainer nodes;

nodes.Create (2);//创建两个节点

PointToPointHelper pointToPoint;//建立一个点对点的拓扑助手帮助生成点对点的连接

pointToPoint.SetDeviceAttribute ("DataRate", StringValue ("5Mbps"));

pointToPoint.SetChannelAttribute ("Delay", StringValue ("2ms"));//设置pointToPoint属性

NetDeviceContainer devices;//创建一个NetDeviceContainer来容纳连接的设备（网卡）列表

devices = pointToPoint.Install (nodes);//依据上面属性pointToPoint给设备安装网卡并创建信道连接 具体描述可以去api文档中阅读

InternetStackHelper stack;//网络协议栈

stack.Install (nodes);//Aggregate implementations of the [ns3::Ipv4], [ns3::Ipv6], ns3::Udp, and ns3::Tcp classes onto the provided node.

Ipv4AddressHelper address;//声明了一个地址生成器对象，设置起始地址和掩码

address.SetBase ("10.1.1.0", "255.255.255.0");

Ipv4InterfaceContainer interfaces = address.Assign (devices);//把地址分配给node上的device 将ip地址和Interface联合封装好放入Ipv4InterfaceContainer 

UdpEchoServerHelper echoServer (9);//创建一个服务器程序，9是端口号

ApplicationContainer serverApps = echoServer.Install (nodes.Get (1));//在1节点上创建UdpEchoServer这个应用程序然后返回return ApplicationContainer (InstallPriv (node));
//InstallPriv (node) 给node安装了udp回显服务程序并返回了指向安装程序的指针
serverApps.Start (Seconds (1.0));

serverApps.Stop (Seconds (10.0));

UdpEchoClientHelper echoClient (interfaces.GetAddress (1), 9);//创建一个客户端程序，利用刚才追踪ip的 Ipv4InterfaceContainer得到1接口的ip地址，即刚才安装服务器的节点，设定远程访问服务器端口号为9

echoClient.SetAttribute ("MaxPackets", UintegerValue (1));//最大数据包个数

echoClient.SetAttribute ("Interval", TimeValue (Seconds (1.0)));//发送间隔

echoClient.SetAttribute ("PacketSize", UintegerValue (1024));

ApplicationContainer clientApps = echoClient.Install (nodes.Get (0));//客户端程序安装

clientApps.Start (Seconds (2.0));

clientApps.Stop (Seconds (10.0));

Simulator::Run ();

Simulator::Destroy ();

return 0;

}