Rule based traffic descriptors for ATM/B-ISDN

Rule based traffic descriptors are getting popular for specifying the intended traffic pattern by the sources and for compliance monitoring at the access to the network. Since these traffic descriptors do not specify the traffic patterns uniquely, the network has to make the connection acceptance/rejection decision based on the worst case mix of patterns compliant with the specified descriptor parameters. Doshi (see GLOBECOM ´93) investigated the worst case behavior of leaky bucket based traffic sources using multiplexer cell loss ratio and individual source cell loss ratios as performance measures. Both the unbuffered and buffered cases were investigated. In this paper, we investigate the unbuffered case further. We study the worst case behavior with respect to collective cell loss rate, individual cell loss rates, and probability of congestion as performance measures. These related but different performance measures are shown to result in very different worst case behaviors. More importantly, we use the results of this investigation to obtain very simple but effective bounds on the individual cell loss ratios, the real performance measures of interest. These bounds are in terms of the cell loss ratio from the multiplexer fed by full rate on-off sources with peak rates during on periods. Thus, while these sources do not necessarily represent the worst case mix of traffic, they can be used in connection acceptance control (CAC) very easily and effectively