Summary of layer functions in the OSI model & TCP/IP Reference Model

The TCP/IP Reference Model (cont.)
•based on the client-server model of communications
•server = a process which provides a service when requested
•client = a process which requests a service
•in general, a client program is run only when it is needed, and is finite(started by the user/application, terminates when service received)
•a server program should run all the time, and is infinite(when started, it runs infinitely, waiting for incoming requests and responding to them)