LAN/MAN interconnection to ATM: a simulation study

The authors compare three strategies, namely, reservation, on-the-fly, and hybrid, for the support of connectionless internet traffic on asynchronous transfer mode (ATM). The comparison is based on a simulation experiment in which a mix of virtual paths (some carrying connectionless traffic, some carrying connection-oriented traffic) are multiplexed on a 150 Mb/s trunk, called the bottleneck trunk. Results based on a variety of measures (cell and burst loss rates, cell delay, and burst delay) show that the on-the-fly approach, which aggressively exploits unused bandwidth, is superior to the reservation scheme, which is handicapped by the renegotiation overhead and the conservative usage of bandwidth. The hybrid scheme exhibits a performance behavior between the other two. This is a bit disappointing, considering the fact that the hybrid scheme is expected to be consistently better than both schemes. Still the hybrid scheme offers some interesting features (e.g. lower delays for the background traffic) which should be further explored by a more extensive examination of the working parameters