Block acknowledgment: redesigning the window protocol

A window protocol based on the block acknowledgment method, in which acknowledgment message has two numbers, m and n, to acknowledge the reception of all data messages with sequence numbers ranging from m to n, is discussed. In the window protocol, message sequence numbers are taken from a finite domain and both message disorder and loss can be tolerated. An initial version of the protocol that uses a simplified timeout action and unbounded sequence numbers is presented, the simplified timeout action in the protocol is replaced by a sophisticated one without disturbing the protocol´s correctness, and the unbounded sequence numbers are replaced by bounded ones while preserving the protocol´s correctness. Remarks concerning other variations of the protocol are also presented