Analysis and implementation of multiplexing techniques in connection-oriented communication networks.

摘要

Future implementations of wired and wireless communication networks are expected to support a variety of multimedia applications with diverse traffic characteristics and quality-of-service (QoS) requirements. To meet these diverse requirements, there are two types of networking technologies, i.e., connectionless and connection-oriented. While some applications, such as small data-file transfers, are best served on a connectionless network, other applications such as large data-file transfers and audio/video applications that have stringent requirements on data rate, delay, delay jitter, and delay-bound violation probability are best served with a connection-oriented network because of its inherent support for QoS.; This dissertation combines an analytical study of a connection-oriented packet-switched scheduling mechanism (a data-plane problem) with a hardware implementation of a signaling protocol for a (connection-oriented) circuit switch (a control-plane problem). For the analytical study, we model and simulate a polling-based scheduling mechanism for its ability to support real-time applications. This is a connection-oriented packet-based bandwidth-sharing mechanism because it requires a call admission control phase to limit the maximum number of communicating endpoints, and it uses packets in the data plane. The real-time application considered in our study is telephony. We develop models to determine appropriate values for operational parameters, such as the number of voice calls that can be simultaneously supported while meeting a predetermined set of quality-of-service requirements (e.g., delay and loss). Our results can be used to dimension a polling-based system, such as the polling-based operational mode of an IEEE 802.11 LAN.; The implementation part of this dissertation is focused on demonstrating that signaling protocols, needed in all connection-oriented networks for the call admission phase, can, in spite of their complexity, be implemented in hardware. Advantages of a hardware implementation are that (a) call setup delay is reduced by at least two-to-three orders of magnitude, and (b) call-handling capacity is increased significantly. By reducing call setup delay, a significant overhead component in connection-oriented networks, resource utilization can be improved. With the high call-handling capacity of a hardware-accelerated signaling engine, connection-oriented switches can better support end-user applications with short-duration calls, which typically have high call arrival rates.