| One of the major trends in the communications world is the emergence and convergence of broadcast communication (for example wireless, CATV, and multi hop networks) and multi service class traffic applications. These systems require access protocols (hop by hop) control and end-to-end control different from those used in conventional multiple access systems, such as local area networks (LANs) or from existing wired systems supporting multimedia traffic.; In this thesis we first focus on deterministic multiple access protocols for wireless broadcast networks supporting delay sensitive applications. A new protocol termed, sliding-window DQRAP, is proposed for this environment and it is shown to be a viable solution.; Next a new software architecture and multiple access protocol, Dynamic Priority Random Access Protocol (DPRAP), is proposed for a CATV broadcast environment. The novelty of this protocol lies in the distribution of control between the channel accessing nodes and central controller. DPRAP assumes that users are homogenous and dynamically adjusts the number of contention opportunities bases on the characteristics of the contending users and controls access to meet the need of the users. Performance of the protocol is obtained through an analytical model. A simulation model is used for optimization of the dynamic assignment of contention opportunities at the central controller. DPRAP is then generalized (G-DPRAP) to support heterogeneous traffic and compared with two non-priority protocols. The results show that G-DPRAP can meet the needs of delay constrained users even when the channel is heavily utilized. Lastly, we turn our attention to the third type of broadcast environment, the multi hop radio network.; To guarantee the end-to-end delivery of traffic for multi service class traffic applications in these networks, we propose a new integrated control constructed of a protocol stack that guarantees deterministic delivery bounds by integrating the access, routing and congestion control at the link and node levels of the network. |
