Performance improvement of ABT protocols with combined bandwidth/buffer reservation

ABT (ATM block transfer) is expected for effectively transferring highly bursty data traffic in ATM networks. In the past work, ABT/IT has been shown to be robust in that its performance is not much affected by the propagation delay when compared with ABT/DT. However, when the traffic load becomes heavy and/or when the number of hop counts of the connection becomes large, the throughput of ABT/IT is drastically decreased. We then propose a new protocol, Buffered-ABT/IT, which makes reservation on the buffer as well as the bandwidth. The approximate analysis method is developed for buffered-ABT/IT. Through numerical examples, we show that it can improve the performance even in the above conditions compared with the existing ABT protocols.