Global congestion control in hybrid ATM/TDMA networks

A new global congestion control scheme is analyzed for the ATM multiplexer node. This scheme is based on the leaky bucket and virtual leaky bucket techniques. It prioritizes transit traffic over local traffic. It ensures quality of service (QOS) to several classes of traffic (i.e., video, voice and data, etc.). A new global congestion control algorithm is designed using the congestion criteria of the adjacent nodes. Early warning cells are transmitted periodically to all adjacent nodes to communicate congestion criteria. The transport users are assumed to be generic ATM sources. The transport users modulate end-to-end flow control parameters, i.e., protocol data unit size in case of video and voice users, and window size in case of data users, based on global congestion status. Simple analytical formulas are derived for global congestion criteria, to represent the required bandwidth to support various traffic classes of service.