CCNA课程TCPIP协议栈.pptVIP

第三章TCP/IP协议栈 本章目标 通过本章的学习，您应该掌握以下内容: 掌握TCP/IP分层模型 掌握三次握手过程 理解OSI和TCP/IP模型的区别和联系 TCP/IP介绍 早期的协议族 全球范围 TCP/IP 协议族 应用层概述 主机到主机层概述 TCP 数据格式 端口号 TCP 端口号 TCP 三次握手 TCP 三次握手 TCP 三次握手 TCP 简单确认 TCP 简单确认 TCP 简单确认 TCP 简单确认 TCP 简单确认 TCP 简单确认 TCP 简单确认 滑动窗口 = 1 TCP 顺序号和确认号 TCP 顺序号和确认号 TCP 顺序号和确认号 TCP 顺序号和确认号 TCP 窗 口 TCP 窗 口 TCP 窗 口 TCP 窗 口 TCP 窗 口 UDP 数据格式 没有顺序号和确认号 Internet 层概述 OSI 网络层对应的是TCP/IP的internet层 IP 数据 协议域 决定上层协议 ICMP协议 ARP协议 ARP协议 ARP协议 ARP协议 映射 IP Ethernet Local ARP RARP协议 RARP协议 RARP协议 RARP协议 映射 Ethernet IP 本章总结 通过本章的学习，您应该掌握以下内容: 掌握TCP/IP分层模型 掌握三次握手过程 理解OSI和TCP/IP模型的区别和联系 问题回顾 OSI和TCP/IP层次模型的区别 TCP/IP的优点 ARP和RARP各用在什么场合 Layer 2 of 5: Layer 2 illustrates how the sending device defines its window buffer as 3 and sends three bytes. Layer 5 of 5: In layer 5, the receiving device acknowledges the 2 bytes and still advertises its window size as 2. Layer 1 of 4: Layer 1 shows the Sequence number is 10. Layer 2 of 4: Layer 2 shows the acknowledgment number is 11. Layer 4 of 4: Layer 4 shows the acknowledgment number is 12. Emphasize: The Sequence and Acknowledgment numbers are directional. The slide highlights the communication going in one direction. The sequence and acknowledgments take place with the sender on the right. TCP provides full-duplex communication. Purpose: This graphic explains the format of UDP. Emphasize: UDP is simple and efficient but not reliable. The UDP segment format includes a source port, a destination port, a length field, and an optional checksum field. It has no sequencing, acknowledgments, or windowing. Example: TFTP uses a checksum. At the end of the transfer if the checksum does not match then the file did not make it. The user is notified and must type in the command again. As a result, the user has become the reliability mechanism. Transition: The next section discusses the network layer of the OSI model and how it corresponds to the TCP/IP internet layer. Purpose: This figure presents a list of the