Timers in OSI protocols-specifications versus implementation

The authors discuss modeling and implementation of timers in OSI protocols. They examine the Estelle, Lotos, and SDL specification languages with emphasis on the features that can be used to express timing. They develop the corresponding models for timer facilities, and discuss possible mechanisms that would support them. As an example drawn from full implementations of the ISO transport and network layers, the authors describe their particular implementation approach for providing timer support.<
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