TCP协议介绍

In this chapter we provide a description of the services provided by TCP for the application layer. we also look at the fields in the TCP header . In the chapter that follow we examine all these header fields in more details, as we see how TCP operates.

Even though TCP and UDP use the same network layer(IP), TCP provides a totally different service to the application layer than UDP does. TCP provides a connection-oriented, reliable , byte stream service

Recall that TCP data is encapsulated in an IP datagram, as shown in Figure 17.1