Time-Estelle: an extended Estelle capable of expressing multimedia QoS parameters

Using a specification language to specify Quality of Service (QoS) parameters for a distributed multimedia system (DMS), it must be able to support the timing relationship between different data of a DMS. Estelle, an internationally standardized formal description technique (FDT) for specifying communication protocols and distributed systems, does not have enough expressing power to specify the time-dependent behaviours of a module of a distributed system. The authors present Time-Estelle, an extended Estelle which can express the timing requirements of a DMS, and then describe the application of Time-Estelle to specify some QoS parameters for a DMS.