计算机网络实验可靠数据传输协议GBN协议的设计与实现

1、实验3：可靠数据传输协议-GBN协议的设计与实现1.实验目的理解滑动窗口协议的基本原理；掌握 GBN 的工作原理；掌握基于UDP 设计并实现一个 GBN 协议的过程与技术。2.实验环境Ø 接入 Internet 的实验主机；Ø Windows xp 或 Windows 7/8；Ø 开发语言：C/C+（或 Java）等。3.实验内容1) 基于 UDP 设计一个简单的 GBN

2、60;协议，实现单向可靠数据传输（服务器到客户的数据传输）。2) 模拟引入数据包的丢失，验证所设计协议的有效性。3) 改进所设计的 GBN 协议，支持双向数据传输； 4.实验设计1) Client:函数列表：各函数功能：函数名传入参数功能client_GBN_5sentence：须发送的内容客户端主函数PACKERsentence：须打包的内容data_len：每包默认长度把要发送的内容按照默认长度进行打包，返回数据包列表与数据包格式senderpl：数据包列表fmt：数据包格式nextseqnum：下一序列号base：基序列号recverne

3、xtseqnum：下一序列号base：基序列号状态转换图：2) Server:状态转换图：3) 数据包结构:发送方：数据包包括序列号与内容接收方：只含接收到的数据包的序号5.实验结果1) Client:2) Server:详细对照：CLIENTSERVER确定服务器与客户端地址、接口socket: ('127.0.0.1', 50000) bindedclient: ('127.0.0.1', 50000)server: ('127.0.0.1', 50001)socket: ('127.0.0.1

4、', 50)client: ('127.0.0.1', 50)server: ('127.0.0.1', 50)准备发送的文本序列：b'x00x00x00x00I am the bone of my ', b'x01x00x00x00sword.Steel is my bo', b'x02x00x00x00dy, and fire is my b', b'x03x00x00x00lood.I have created ', b'x04x00x00x00over a thousand

5、blad', b'x05x00x00x00es.Unknown to Death,', b'x06x00x00x00Nor known to Life.Ha', b'x07x00x00x00ve with stoodpain t', b'x08x00x00x00o create many weapon', b'tx00x00x00s.Yet,those hands wi', b'nx00x00x00ll never hold anythi', b'x0bx00x00x00ng.So

6、as I pray, Unl', b'x0cx00x00x00imited Blade Worksx00x00'进行收发start timergo to next packetrecver: go on!base: 0start timergo to next packetrecver: go on!base: 1start timergo to next packetrecver: go on!base: 2start timergo to next packetrecver: go on!base: 3start timergo to next packetrecv

7、er: go on!base: 4start timergo to next packetrecver: go on!base: 5start timergo to next packetrecver: go on!base: 6start timergo to next packetrecver: go on!base: 7start timergo to next packetrecver: go on!base: 8start timergo to next packetrecver: go on!base: 9start timergo to next packetrecver: go

8、 on!base: 10start timergo to next packetrecver: go on!base: 11start timergo to next packet0 I am the bone of myb'x00x00x00x00'1 sword.Steel is my bob'x01x00x00x00'2 dy, and fire is my bb'x02x00x00x00'3 lood.I have createdb'x03x00x00x00'4 over a thousand bladb'x04x

9、00x00x00'5 es.Unknown to Death,b'x05x00x00x00'6 Nor known to Life.Hab'x06x00x00x00'7 ve with stood pain tb'x07x00x00x00'8 o create many weaponb'x08x00x00x00'9 s.Yet,those hands wib'tx00x00x00'10 ll never hold anythib'nx00x00x00'11 ng.So as I pray, Unlb'x0bx00x00x00'12 imited Blade Works发送完成时，直接结束。超时两次后结束。此处不另设结束信号。SENDER:FINI