Study of variable bandwidth allocation in integrated services local area networks.

摘要

Dynamic bandwidth allocation plays an important role in integrated services networks. Effective bandwidth management can improve the overall performance of the network significantly. In integrated services networks, different types of traffic coexist. To serve these different types of traffic satisfactorily, hybrid switching is commonly used. Hybrid switching is an integration of circuit switching and packet switching in the same network. In this thesis, dynamic bandwidth allocation is studied to provide satisfactory hybrid switching performance. Specifically, we will study how to allocate bandwidths for continuous bit rate (CBR) traffic served by circuit switching and variable bit rate traffic (VBR) served by packet switching. The performance measure is based on the blocking probability of CBR traffic and the time delay of VBR traffic. Therefore, the objective of the dynamic bandwidth allocation is to maintain balance between blocking probability and delay under various traffic conditions. To accomplish this, the dynamic bandwidth allocation algorithms consists of traffic intensity estimation, traffic performance prediction, and performance optimization. A simulation is written to demonstrate the algorithm for various traffic scenarios.