Windowing algorithms based on distributed queue of an ATM switch

Abstract

Broadband integrated services digital networks (B-ISDN) will provide various multimedia services generating multi-class traffic and multicast traffic, and asynchronous transfer mode (ATM) switches are the fundamental element of the B-ISDN. For this reason, the design of ATM switches supporting such traffic is very important. Meanwhile, the windowing algorithm is a valuable method to enhance the performance of input queueing switches. In this dissertation work, we studied distributed control schemes for the windowing algorithm of an ATM switch. First, we have proposed a new distributed scheduling scheme based on distributed queue for input queueing ATM switches. We call the new proposed scheme as the distributed queue windowing (DQW) scheme. The DQW scheme has riginated from the distributed queue dual bus (DQDB) protocol and has windowing effect like the look-ahead contention resolution algorithm. Nevertheless, the DQW scheme does not need multiple phases of contention resolution unlike the look-ahead contention resolution algorithm. This feature makes the DQW switch with large window be implementable. Simulation results have proven that the proposed scheme has good throughput performance in case of large window size. Second, we proposed two multi-priority DQW schemes for multi-class service: Multi-Turn Reservation (MTR) scheme and Single-Turn Reservation (STR) scheme. These schemes are two modifications from the original DQW scheme. The multi-priority DQW schemes have global priority characteristic; the higher-priority cells are not influenced by lower-priority cells in the entire system. Hence, real-time services can be provided stably by using the high-priority level. Non-realtime services which are insensitive to delay can be provided efficiently by using the low-priority level and large window. Moreover, the single-turn reservation scheme can be implemented with no restriction on the switch dimension. We have shown the performance of each priority level for...