Prof. A.E. Krzesinski
Department of Computer Science
University of Stellenbosch, South Africa

Value-Based Bandwidth Re-Configuration in Connection-Oriented Networks

Market price systems constitute a well understood class of mechanisms that under certain conditions provide effective decentralization of decision making with minimal communication overhead.

This seminar presents a model of a co-operative market for bandwidth re-allocation in connection-oriented networks.A bandwidth manager is assigned to each end-to-end route. The managers are autonomous, acting without centralized control from a system coordinator and behave entirely according to local rules. The managers are aware of local resource demands and bandwidth prices. The managers re-allocate bandwidth among themselves in order to maintain the Quality of Service (QoS) of their routes.

We present a simulation model of the bandwidth market. Two fictitious network models are investigated: a 30-node 46-link European network and a 23-node 37-link USA network. The European network model considers traffics whose average parameters are time-invariant. In the USA network model the average call arrival rates are subject to time dependent variations which could model a daily traffic pattern. Furthermore, the USA network nodes are located in different time zones. The time zones give rise to local variations in the call arrival rates which capacity re-allocation may be able to exploit in order to improve the route revenues.
The simulation studies reveal that bandwidth re-allocation substantially reduces the revenue lost by the network due to long timescale variations in the traffic and to random fluctuations in the traffic arrival rates.