Resource Allocation for Quality of Service Provision in Buffered Crossbar Switches with Traffic Aggregation

The capability of providing quality of service (QoS) in packet switches of computer networks is critical to implementation of distributed multimedia systems. The buffered crossbar switching architecture is promising to achieve high performance without complex implementation. In this paper, we study the problem of resource allocation to aggregated traffic classes in buffered crossbar switches for QoS provision. We develop techniques for determining the required amount of bandwidth and buffer space for aggregated traffic classes to provide delay performance guarantee, and analyze the impact of traffic aggregation on resource utilization in buffered crossbar switches. We consider two traffic aggregation cases: aggregation of a set of flows with identical traffic profiles, and aggregation of a set of flows with different traffic parameters. For both cases, we compare the amount of resources required by the aggregated class and by the set of individual flows for guaranteeing identical delay objectives. We find that traffic aggregation reduces both bandwidth and buffer space requirements, and the amount of resources saved by aggregation is associated with multiple factors, including the delay objective, the arrival traffic parameters, and the number of flows aggregated into one class.