Weighted Fairness Guarantee for Scalable Differentiated Services (DiffServ)

Currently there is not enough work on the Internet weighted fair bandwidth sharing without per-flow management, especially when both UDP and TCP flows of different RTTs and different bandwidth targets coexist. This paper contains two contributions: 1 ) A mechanism called SCALE-WFS, Scalable Core with Aggregation Level labEling Weighted Fair bandwidth-Sharing, is presented to achieve near-optimal Max-Min weighted fairness without per-flow management at core routers, in the context of differentiated service networks. Through extensive simulation and simple analysis, we show the performance problems with current solutions and propose SCALE-WFS to solve these problems. This scheme works effectively for different flow weights, RTTs, protocols (TCP and UDP), under the scenarios of different bandwidth provisioning and multiple congested gateways, all of which we consider the basic requirements for a practical solution. 2 ) Apart from “per-flow” and completely “core-stateless”, SCALE represents a third management level—the label-based flow “aggregation” level. It reduces the information redundancy in the “per-flow” and surpasses the performance of the “core-stateless”. This is important to differentiated service networks where we try to avoid the non-scalability of per-flow management while keeping its good Quality of Services. In this paper, we show that SCALE-WFS is effective and scalable, robust and extensible. Keywords— DiffServ, Max-Min Fairness, Profile Rate, Aggregation, Packet Dropping Probability.