Performance Modeling of Protocols

Abstract

One of the unpleasant surprises in many communication systems has been the difficulty of designing the protocols used to meet the performance requirements of the system application. We include system correctness as a performance requirement. Some of the problems are common to the early design phase of any large program, but the lack of adequate design tools is more serious in the case of concurrent systems, since the timing anomalies and other glitches are extremely hard to predict by ad hoc methods. This paper describes two formal notational mechanisms that assist the modeler in discovering and defining all of the assumptions that go into a system design. These mechanisms are being incorporated into a simulation laboratory aimed at providing complete formal specifications of digital communication systems at the early design stages.