思科网络技术学院教程(第二章高层协议).ppt

高层协议 第二章 应用层与会话层 应用层 选择网络应用支持用户的事务应用 表示层 为应用层提供代码格式的转换 会话层 支持在不同主机上对等应用程序之间的对话 传输层 传输层概览 将会话层数据分割成较小的分组 建立端到端的连接 将分组从一端主机发送到另一端主机 保证数据可靠传输 面向连接的会话 流量控制 流量控制 流量控制 流量控制 流量控制 窗口技术 窗口技术 窗口技术 窗口技术 窗口技术 窗口技术 窗口技术 正向确认 正向确认 正向确认 正向确认 正向确认 正向确认 正向确认 正向确认 分组如何穿过通信网络？ Computer Representation of Meaningful Information Compression Techniques Establish and maintain end-to-end connection * * Copyright ?1998, Cisco Systems, Inc. ICRC_revision_11.3 Copyright ?1998, Cisco Systems, Inc. ICRC_revision_11.3 Copyright ?1998, Cisco Systems, Inc. ICRC_revision_11.3 事务应用 字处理 图表 电子表格 数据库 设计/制造 课题计划 其他 网络应用 电子邮件 文件传输 远程访问 客户端/服务器模式处理 信息定位 网络管理 其他 ?Graphics?Visual Images PICT TIFF JPEG GIF ?Text?Data ASCII EBCDIC Encrypted ?Sound?Video MIDI MPEG QuickTime login: 网络文件系统 (NFS) 结构化查询语言 (SQL) 远程过程调用 (RPC) X 窗口系统 互连网浏览器 DNA 会话控制协议 (SCP) Service Request Service Reply Copyright ?1998, Cisco Systems, Inc. ICRC_revision_11.3 同步 同步 确认 连接协商 数据传输 (发送分组) Sender Receiver 连接建立 Buffer Full  Transmit Sender Receiver Buffer Full  Transmit Not Ready Stop Sender Receiver Buffer Full Process Segments Buffer OK Transmit Not Ready Stop Sender Receiver Buffer Full Process Segments Buffer OK Transmit Not Ready Stop Ready Go Sender Receiver Buffer Full Process Segments Buffer OK Transmit Not Ready Stop Ready Go Resume Transmission Sender Receiver Window size = 1 Send 1 Receive 1 Sender Receiver Window size = 1 Send 1 Receive 1 Ack 2 Sender Receiver Window size = 1 Send 1 Receive 1 Ack 2 Send 2 Receive 2 Sender Receiver Window size = 1 Send 1 Receive 1 Ack 2 Send 2 Receive 2 Ack 3 Sender Receiver Window size = 1 Send 1 Receive 1 Ack 2 Send 2 Receive 2 Ack 3 Send 1 Send 2 Receive 1 Receive 2 Window size = 3 Send 3 Receive 3 Sender Receiver Sender Receiver Window size = 1 Send 1 Receive 1 Ack 2 Send 2 Receive 2 Ack 3 Send 1 Send 2 Receive 1 Receive 2 Window size = 3 Send 3 Receive 3 Ack 4 Sender Receiver Sender Receiver Window size = 1 Send 1 Receive 1 Ack 2 Send