This Recommendation addresses functions and parameters for traffic and congestion control in the B‑ISDN.

A user-network and an inter-network traffic contract are defined in terms of a traffic descriptor that includes traffic parameters and associated tolerances of an ATM layer transfer capability and of quality of service requirements associated to a QoS class. Relevant traffic parameters and generic conformance definitions for these parameters are specified. ATM transfer capabilities that make use of these traffic parameters to allow for different combinations of QoS objectives and multiplexing schemes and specific conformance definitions applying to these ATM transfer capabilities are provided.

In addition, traffic control and congestion control functions are further specified, among which are traffic parameter control functions at user-network and inter-network interfaces. Some specific traffic control interworking configurations are described.

Finally, procedures for traffic control, congestion control and resource management are defined. This includes specific formats and information supported by resource management cells.