See protocol stack in Webster''s New World Hacker Dictionary
Protocols within a suite are designed with a very specific purpose, and each protocol typically communicates with two others in the stack. The lowest protocol deals with the low-level physical interaction of hardware, whereas user applications deal with only the uppermost layers. Protocol stacks are generally divided into three parts dealing with applications, transport, and media.
See protocol stack in Computer
The set of protocols used in a communications network. A protocol stack is a prescribed hierarchy of software layers, starting from the application layer at the top (the source of the data being sent) to the data link layer at the bottom (transmitting the bits on the wire). The stack resides in each client and server, and the layered approach lets different protocols be swapped in and out to accommodate different network architectures. For more details about each layer, see OSI model.
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