OSI service specification: SAP and CEP modelling

ABSTRACT

Within the effort of ISO standarization, service specifications have been thought to be an important tool for formal verification of protocols. The paper discusses the modelling of some concepts quite related with the service: service access points and abstract service primitives. Firstly, ISO concepts are explained. Then, a service architectural model is developed as a refinament of the service access point idea using the connection end point concept. A finite state machine approach is shown to specify the behavior of the modules of such architecture. This lead us to consider the service access point represented as a single state automaton that consists of several connection end point automata. Thus, service access points allow the specification of services, and provide an abstraction of interfaces between adjacent layers of the Open System Interconnection model of ISO.

REFERENCES

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INDEX TERMS

Classification:
  C. Computer Systems Organization
  C.2 COMPUTER-COMMUNICATION NETWORKS
      C.2.1 Network Architecture and Design

          Nouns: OSI
      C.2.2 Network Protocols
          Subjects: Protocol verification

General Terms:
Design, Standardization