A compositional approach for constructing communication services and protocols
The complexity of designing communication protocols has lead researchers to develop various techniques for designing and verifying protocols. One of the most important techniques is a compositional technique. Using a compositional technique, a large and complex protocol is designed and verified by composing small and simple protocols which are easy to handle, design and verify. Unlike the other compositional approaches, we propose compositional techniques for simultaneously composing service specifications and protocol specifications based on Formal Description Techniques (FDTs) called LOTOS. The proposed techniques consider alternative, sequential, interrupt and parallel composition of service specifications and protocol specifications. The composite service specification and the composite protocol specification preserve the original behaviour and the correctness properties of individual service specifications and protocol specifications. We use the weak bisimulation equivalence (approximate to), to represent the correctness properties between the service specification and the protocol specification. When a protocol specification is weak bisimulation equivalent to a service specification, the protocol satisfies all the logical properties of a communication protocol as well as provides the services that are specified in the service specification.
composition service protocol fdt alternative sequential interrupt parallel