Abstract :
Initiatives to identify user requirements for time-critical communications architectures (TCCA) and for quality of service (QoS) have led to standardisation work that will be widely applicable. The concepts and mechanisms which are described have relevance across almost all application areas. Eventually, OSI systems will be able to be selected for their performance as well as for their functionality, and their operational behaviour will be able to be monitored and tuned to meet the precise requirements of their users
