Deterministic rule based traffic descriptors for broadband ISDN: worst case behavior and connection acceptance control

Deterministic rule based traffic descriptors in general and leaky bucket based (LBB) traffic descriptors in particular, offer advantages for specifying and monitoring traffic in ATM based B-ISDN. However, these traffic descriptors do not specify the traffic patterns uniquely. This poses new challenges to be addressed. Two of the important ones are: (i) definition of the worst case behavior and characterization of the worst case traffic compliant with the LBB traffic descriptors; (ii) connection acceptance controls (CAC) for LBB sources (in particular, the applicability of `equivalent bandwidth´ concept to simplify the CAC procedure). The author addresses these questions with respect to the performance measures based on cell loss ratios. For most part, the author uses the multiplexer cell loss ratio (CLR) as the performance measure and defines the worst case behavior for homogeneous and general heterogeneous environments. Both unbuffered and buffered cases are considered. For the unbuffered resources and homogeneous environment, the author shows that the full rate periodic on-off behavior is the worst. In the heterogeneous environment, the full rate on-off behavior is the worst only in a limited sense and the use of a collective performance measure results in anomalous relationships between the source behavior and the CLR. Interesting properties of the worst case behavior with more appropriate performance measures are briefly discussed