Cost-Effective Deployment of Bandwidth Partitioning in Broadband Networks

We consider the issue of bandwidth partitioning in a multi-rate broadband network. Requests for a number of different types of connection are offered to the network. For the purposes of connection admission and resource allocation, we assume that it is possible to allocate an effective bandwidth to a single connection of each type. The network manager has the problem of implementing an admission control scheme to maximise the profit earned from the network. Our focus here is the extent to which it is a good idea to partition the bandwidth on the physical links to form reserved end-to-end logical links corresponding to the origin-destination pairs. It is clear that implementation of such partitioning will lead to a loss of multiplexing opportunities. However, in a network with end-to-end logical links, costs related to overhead such as route selection, admission control and signalling may be much reduced. This effect may outweigh the loss of revenue due to missing out on multiplexing opportunities. We investigate the nature of this trade-off, by designing optimal or near-optimal partitioned networks using efficient algorithms for finding routes and allocating bandwidth to end-to-end logical links on a fixed underlying physical network. We then calculate the net rate of earning profit under each of the schemes as a function of the ratio of overhead costs to call revenue. Our conclusion is that it is cost-effective to partition bandwidth under a variety of realistic assumptions about revenue rates and overhead costs. [PUBLICATION ABSTRACT]