Abstract :
A tutorial introduction to the function and construction of communications software in modern teleprocessing systems is presented, Communication functions include network control, message preprocessing and queuing, and error recovery. These functions are provided by the communication subsystem, which includes components of the supervisory system, special-purpose software, and cooperating peripheral processors. The construction of communication subsystems is described, including aspects of both software and hardware, in the context of a multiprogramming and multiprocessing environment. The application of distributed-function processing, virtual memory, and segmentation techniques to the design of these subsystems is discussed.