New communication protocols from old

摘要

The power tier automaton (PTA) is introduced as a model of preference for representing and manipulating systems in general, computer architectures and, in particular, communication networks and their protocols. The PTA is superior to Petri nets, both in computing power (Turing machine power) and in ease and selectivity of representation. The tier automaton, a species of the PTA, is used to represent networks and protocols to a greater advantage than other existing models. Homomorphisms and reachable-domain (r.d.) homomorphisms on tier automata are introduced and used to manipulate two distinct protocols for reliable full-duplex transmission over half-duplex lines, both of whose images are the same familiar alternating-bit protocol.