Performance of collision resolution algorithms for multiple access broadcast networks

Abstract

The main objectives of this dissertation are to suggest some collision resolution algorithms (CRAs) in a multiple access broadcast network and to investigate their performance characteristics when limited sensing and full feedback sensing schemes are applied. The tree protocol and its variants have been studied as stable and effective methods of resolving collision. Among them, the tree protocol with collision detection (Tree/CD) recently attracted considerable attention because of better throughput and delay performance than any other CRAs including the Ethernet protocol. However, its performance has not been sufficiently studied yet. Thus, we first analyze the delay performance of the Tree/CD protocol. Considering the regenerative property of the delay process, we derive the upper and lower bounds of the average packet delay. Over a wide range of arrival rates and slot length T, our analysis agrees closely with simulation results. We also investigate a collision resolution protocol that utilizes the information of collision multiplicity. With the number of collided packets known, the system shows performance enhancement over the Tree/CD protocol in both throughput and delay characteristics. This results from the fact that arrival intervals are split adaptively, not just halved, according to the number of packets that were involved in the collision. In addition, we analyze the throughput performance of the limited sensing Tree/CD protocol. It is shown that, though a little degradation is observed because of a restiction that the users cannot listen to all feedbacks, the throughput becomes almost the same as that of a full-feedback system when the allowed successive slots in a CRI is as large as 5. Then, we examine the performances of collision resolution protocols with random packet sizes. With packets of arbitrary length, the protocol need to enable users to detect the end of transmission. The delay and variance characteristics of both the ternary and binary ...