滑动窗口协议仿真（2024）

1.题目描述

滑动窗口协议以基于分组的数据传输协议为特征，该协议适用于在数据链路层以及传输层中对按 顺序传送分组的可靠性要求较高的环境。在长管道传输过程（特别是无线环境）中，相应的滑动窗口 协议可实现高效的重传恢复。附录 3 给出了一个选择性重传的滑动窗口协议的简单实现，以此为参考， 设计并实现一个滑动窗口协议的仿真，显示数据传送过程中的各项具体数据，双方帧的个数变化，帧 序号，发送和接受速度，重传提示等。

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2.程序演示

 这里我们使用Socket来模拟滑动窗口协议，实现了双方帧的个数变化，帧序号，发送和接受速度控制，重传显示。

控制帧发送速度

双方帧的个数变化

丢失包

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3.参考代码

接收端代码

#include <winsock2.h>
#include <iostream>
#include <list>
#include <time.h>
#include <unistd.h>
#pragma comment(lib, "ws2_32.lib")
using namespace std;//函数说明------------------------------
DWORD WINAPI ThreadFun(LPVOID lpThreadParameter);void init_app();//---------------------------------------
WSADATA wd;
SOCKET Socket;
sockaddr_in addrClient;
int len = sizeof(sockaddr_in);//变量------------------------------
struct Data {//消息类型定义int Type_ACK = 0;int Type_Msg = 1;int Type_Requst = 2;int Type_Retransmission=3;//消息内容int Msg_Code = 0;//消息序号int Msg_Type = 1;//消息类型int Msg_ACK=0;//是否已经ACK了char *Msg_Content[128];//消息内容int Send_WinSize = 4;//发送窗口大小
};Data Send_Msg_Data;
Data *Get_Msg_Data;
char Get_buf[1024] = {0}, send_buf[1024] = {0};int main() {//提示=======================================================================cout << "滑动窗口协议仿真(Socket模拟)_接收方" << endl;//初始化=======================================================================init_app();//==========================================================================
}DWORD WINAPI ThreadFun(LPVOID lpThreadParameter) {// 接受数据SOCKET This_Socket = (SOCKET) lpThreadParameter;cout << "*连接成功" << endl;// 循环接收客户端数据int ret = 0;do {//接收ret = recv(This_Socket, Get_buf, sizeof(Get_buf), 0);Get_Msg_Data = (Data *) Get_buf;cout << "\n收到消息:" << endl;cout << "类型:" << Get_Msg_Data->Msg_Type << " 序号: " << Get_Msg_Data->Msg_Code << endl;//发送if (Get_Msg_Data->Msg_Type==3){Send_Msg_Data.Msg_Type =3;} else{Send_Msg_Data.Msg_Type = 0;}Send_Msg_Data.Msg_Code = Get_Msg_Data->Msg_Code;memcpy(send_buf, &Send_Msg_Data, sizeof(Data));sleep(1);if (send(This_Socket, send_buf, sizeof(send_buf), 0) > 0) {cout << "\n回复帧:" << Send_Msg_Data.Msg_Code << " ACK" << endl;} else {cout << "\n失败回复:" << Send_Msg_Data.Msg_Code << " ACK" << endl;}} while (ret != SOCKET_ERROR && ret != 0);return 0;
}void init_app() {if (WSAStartup(MAKEWORD(2, 2), &wd) != 0) {cout << "WSAStartup Error:" << WSAGetLastError() << endl;return;}// 创建流式套接字Socket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);if (Socket == INVALID_SOCKET) {cout << "socket error:" << WSAGetLastError() << endl;return;}//绑定端口和ipsockaddr_in addr;memset(&addr, 0, sizeof(sockaddr_in));addr.sin_family = AF_INET;addr.sin_port = htons(8000);addr.sin_addr.s_addr = inet_addr("127.0.0.1");//服务端bind绑定if (bind(Socket, (SOCKADDR *) &addr, len) == SOCKET_ERROR) {cout << "bind Error:" << WSAGetLastError() << endl;return;}// 监听listen(Socket, 5);//主线程循环接收客户端的连接while (true) {cout << "*等待连接..." << endl;// 接受成功返回与client通讯的SocketSOCKET Client = accept(Socket, (SOCKADDR *) &addrClient, &len);if (Client != INVALID_SOCKET) {// 创建线程，并且传入与client通讯的套接字HANDLE hThread = CreateThread(NULL, 0, ThreadFun, (LPVOID) Client, 0, NULL);CloseHandle(hThread); // 关闭对线程的引用}}
}

发送端代码

#include<winsock2.h>//winsock2的头文件
#include<iostream>
#include <list>
#include <ctime>#pragma comment(lib, "ws2_32.lib")using namespace std;//定义========================
void Init_Socket();void *SendMsg(void *pVoid);int getRand(int min, int max);void Sycn();void Send_Win_Move();void Retransmission(int Num);//发送的数据=======================
struct Data {//消息类型定义int Type_ACK = 0;int Type_Msg = 1;int Type_Requst = 2;int Type_Retransmission = 3;//消息内容int Msg_Code = 0;//消息序号int Msg_Type = 1;//消息类型int Msg_ACK = 0;//是否已经ACK了char *Msg_Content[128];//消息内容int Send_WinSize = 4;//发送窗口大小
};//默认参数=======================
int Rand_Num = 5;//随机概率1/5
int Receiver_WinSize = 10;
int Send_WinSize = 5;
int Send_Size = 10;
int ACK_OutTime = 10;
int Send_Num = 100;
char *Send_Msg = "0123456789";
SOCKET Socket;
int Win_Now_Size = 0;//消息列表=======================
list<Data> MSG_Win_List;
Data Send_Msg_Data;
Data *Get_Msg_Data;
Data *Temp_Msg_Data;
int Num = 0;
char send_buf[1024] = {0}, Get_buf[1024] = {0};void init_data() {char auto_data;//提示=======================================================================cout << "*====滑动窗口协议仿真(Socket模拟)_发送方====*\n";cout << "\n-------------------------------\n";cout << " 请输入必要参数(y/n):";cin >> auto_data;if (auto_data == 'n') {cout << " 发送窗口: ", cout << Send_WinSize << endl;cout << " 消息帧数: ", cout << Send_Num << endl;
//        cout << " 发送内容: ", cout << Send_Msg << endl;} else {cout << " 发送窗口: ", cin >> Send_WinSize;cout << " 消息帧数: ", cin >> Send_Num;}cout << "-------------------------------" << endl;system("pause");}int main() {init_data();Init_Socket();//接收服务端的消息pthread_t tids;pthread_create(&tids, NULL, SendMsg, &Socket);//随时给服务端发消息do {int ret = 0;do {ret = recv(Socket, Get_buf, sizeof(Get_buf), 0);Get_Msg_Data = (Data *) Get_buf;if (ret != SOCKET_ERROR && ret != 0) {cout << "\n\n\t==>收到帧:" << " ACK: " << Get_Msg_Data->Msg_Code << endl;list<Data>::iterator iter;for (iter = MSG_Win_List.begin(); iter != MSG_Win_List.end(); iter++) {if (Get_Msg_Data->Msg_Code == iter->Msg_Code) {(*iter).Msg_ACK = 1;if (Get_Msg_Data->Msg_Type == 3) {cout << "\n\t重传删除了一个" << endl;Win_Now_Size--;MSG_Win_List.erase(iter);}break;}}Sycn();}} while (ret != SOCKET_ERROR && ret != 0);} while (true);//关闭监听套接字closesocket(Socket);WSACleanup();}void Init_Socket() {WSADATA wd;//加载winsock2的环境if (WSAStartup(MAKEWORD(2, 2), &wd) != 0) {cout << "WSAStartup  error：" << GetLastError() << endl;return;}//创建流式套接字Socket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);if (Socket == INVALID_SOCKET) {cout << "socket  error：" << GetLastError() << endl;return;}//连接服务器sockaddr_in addr;addr.sin_family = AF_INET;addr.sin_port = htons(8000);addr.sin_addr.s_addr = inet_addr("127.0.0.1");int len = sizeof(sockaddr_in);if (connect(Socket, (SOCKADDR *) &addr, len) == SOCKET_ERROR) {cout << "connect  error：" << GetLastError() << endl;return;}
}void *SendMsg(void *pVoid) {do {Send_Win_Move();Sycn();system("pause");Send_Msg_Data.Msg_Code = Num;Send_Msg_Data.Msg_Type = 1;memcpy(send_buf, &Send_Msg_Data, sizeof(Data));if (Win_Now_Size == Send_WinSize) {list<Data>::iterator iter;for (iter = MSG_Win_List.begin(); iter != MSG_Win_List.end(); iter++) {if (iter->Msg_ACK == 0) {Send_Msg_Data.Msg_Code = iter->Msg_Code;Send_Msg_Data.Msg_Type = 3;memcpy(send_buf, &Send_Msg_Data, sizeof(Data));if (send(Socket, send_buf, sizeof(send_buf), 0) > 0) {cout << "\n\t<==发送重传帧:" << iter->Msg_Code << endl;} else {cout << "\n\t<==失败发送重传帧:" << iter->Msg_Code << endl;}break;}}continue;}if (getRand(1, Rand_Num) == Rand_Num)//随机丢失{cout << "\n\t<=xxxx=随机丢失帧:" << Num++ << endl;} else {if (send(Socket, send_buf, sizeof(send_buf), 0) > 0) {cout << "\n\t<==发送帧:" << Num++ << endl;} else {cout << "\n\t<<==失败发送帧:" << Num++ << endl;}}Win_Now_Size++;Send_Num--;MSG_Win_List.push_back(Send_Msg_Data);} while (Send_Num > 0);
}void Send_Win_Move() {if (MSG_Win_List.begin()->Msg_ACK == 0) return;list<Data>::iterator iter=MSG_Win_List.begin();while (iter->Msg_ACK==1){MSG_Win_List.erase(iter);Win_Now_Size--;iter=MSG_Win_List.begin();}cout << "\n\t窗口移动了" << endl;
}int getRand(int min, int max) {return (rand() % (max - min + 1)) + min;
}void Sycn() {cout << "\n\t------------------------------" << endl;cout << "\t当前发送窗口:" << Send_WinSize << "\t可用窗口大小:" << Send_WinSize - Win_Now_Size << endl;list<Data>::iterator iter;for (iter = MSG_Win_List.begin(); iter != MSG_Win_List.end(); iter++) {cout << "\t#帧序号:" << iter->Msg_Code << "\t#是否ACK:" << iter->Msg_ACK << endl;}cout << "\t------------------------------" << endl;
}

 4.导入ws2_32库到Clion :

导入ws2_32库到Clion项目-CSDN博客

 

 2024 HNUST计算机网络课程设计-(ᕑᗢᓫ∗)˒芒果酱-参考文章

（代码可以参考，૮₍ ˃ ⤙ ˂ ₎ა 但同学们要认真编写哦）
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1、网络聊天程序的设计与实现
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2、Tracert 与 Ping 程序设计与实现
Tracert 与 Ping 程序设计与实现（2024）-CSDN博客
3、滑动窗口协议仿真
滑动窗口协议仿真（2024）-CSDN博客
4、OSPF 路由协议原型系统设计与实现
OSPF 路由协议原型系统设计与实现-CSDN博客
5、基于 IP 多播的网络会议程序
基于 IP 多播的网络会议程序（2024）-CSDN博客
6、编程模拟 NAT 网络地址转换
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7、网络嗅探器的设计与实现
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8、网络报文分析程序的设计与实现
网络报文分析程序的设计与实现（2024）-CSDN博客
9、简单 Web Server 程序的设计与实现
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10、路由器查表过程模拟

计算机网络 - 路由器查表过程模拟 C++(2024)-CSDN博客