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The TCP/IP Guide  9  TCP/IP Lower-Layer (Interface, Internet and Transport) Protocols (OSI Layers 2, 3 and 4)       9  TCP/IP Transport Layer Protocols            9  Transmission Control Protocol (TCP) and User Datagram Protocol (UDP)                 9  TCP/IP Transmission Control Protocol (TCP)

TCP/IP Transmission Control Protocol (TCP) 1 TCP Overview, History and Standards

As I mentioned in the previous section overview, the Transmission Control Protocol (TCP) is a critically important part of the TCP/IP suite. It's also a fairly complicated protocol, with a lot of important concepts and mechanisms to understand. The old joke says the best way to eat an elephant is “one bite at a time”. Similarly here, we can best comprehend the operation of this complicated protocol by going slowly, starting with a high-level look at it, where it came from, and what it does in general terms.

In this section I begin our look at TCP with an introduction to the protocol. I first provide an overview and history of TCP, and describe the standards that define it. I then give a “bird's eye” view of TCP by describing it in two important ways. I illustrate what TCP actually does by listing its functions, and then explain how TCP works by describing its most important characteristics. This will give you a feel for what TCP is all about, and hopefully set the stage for the more complex technical discussions in subsequent sections.

TCP/IP Transmission Control Protocol (TCP) 1 TCP Overview, History and Standards