Network management and control of protocols

The authors describe some of the special requirements placed on the protocols that must function in a multidomain environment. Taking these requirements into consideration, they describe a novel protocol structure called a bipartite protocol, which is based on the use of tokens. They show that the use of bipartite protocols makes it possible to perform a number of functions, namely to systematically explore subgraphs of the global state diagram representing the protocol, with predetermined numbers of messages in the channel queues, thereby facilitating the analysis of protocols; to generate tightly synchronized protocols or sections of protocols, thereby controlling the build up of queues in the channels; and to implement sections of network control systems using the tokens in the bipartite protocol structure. Examples are given for X.75, illustrating both the analysis of protocols and the control of channel contents