Formal specification of QoS properties

We describe the specification of communication services, with special emphasis being placed on the use of the Temporal Logic of Actions (TLA) to describe the behaviours involved. We show how, startingfrom Message Sequence Charts, this temporal logic may be used to describe The Joint Viewing and Tele Operating Service (JVTOS) and its associated functions; and so lead on to the specification of QoS parameters. We discuss the approach that was taken to determine the exact nature of the Quality of Service parameters, and how the method may be used to extend the specification, and probe further aspects of the services and protocols involved