The buffer-bandwidth trade-off curve is convex

To achieve a constant overflow probability, the two queueing resources, viz . buffer and bandwidth, can be traded off. In this paper we prove that, und er general circumstances, the corresponding tradeoff curve is convex in the 'many-sources scaling'. This convexity enables optimal resource partitioni ng in a queueing system supporting heterogeneous traffic, with heterogeneou s quality-of-service requirements.