Protocol conversion—correctness problems
Simon S. Lam · 1986
Consider the problem of providing a logical channel for message exchange between two user processes in a network environment. When is protocol conversion needed? To answer this question, we first define a model of layered architectures. Specifically, three stepwise refinement rules are given. Any architecture that can be obtained by a sequence of applications of the stepwise refinement rules is said to be well-structured. We show that this class of well-structured architectures has several correctness properties. It is also very general and includes many well-known networking and internetworking architectures in the literature. Logical connectivity in such an architecture is defined recursively. As a result, to determine if a logical channel can be provided between two user processes, it is sufficient to examine peer protocols specified for each level of the architecture's hierarchy of processes one at a time. Thus the original problem reduces to the problem of determining if a set of processes will interoperate.