Random access for ATM LANs and WANs

We investigate the performance of two simple random access techniques for ATM LANs and WANs. In the first approach, called tell-and-go, the source transmits its messages immediately in the form of bursts as soon it receives the message from its application layer (or some higher layer). In the second approach, called tell-and-wait, the source first reserves the bandwidth along the virtual circuit using a short request message. The burst is transmitted only after the requested bandwidth has been allotted. Our qualitative results indicate that the tell-and-go protocol is suitable for ATM WANs whereas the tell-and-wait protocol is suitable for ATM LANs. Our quantitative results further give the performance comparisons of the two techniques with respect to the propagation delay, burst size, and burst peak rate