Fair Bandwidth Allocation and Buffer Management in Hybrid Network Gateways

Roshni Srinivasan, Ravichander Vaidyanathan and John S. Baras

Number: CSHCN TR 2000-11, Year: 2000, Advisor: John S. Baras

Abstract

In this paper, we present an efficient and fair resource allocationscheme for scheduling and buffer management in a bottleneck hybridsatellite-terrestrial network gateway with per-flow TCP queues.

Ourfirst contribution is the use of Fair Queueing in conjunction withProbabilistic Fair Drop, a new buffer management policy to allocatebandwidth and buffer space in the gateway, to ensure that all TCPflows threading the gateway achieve high end-to-end throughput andfair service.

Our second contribution is to introduce the concept ofbuffer dimensioning to alleviate the inherent bias of the TCPalgorithm towards connections with large Round Trip Time.

In supportof each of these contributions, we report on extensive simulationresults. Our scheme outperforms other resource allocation schemesreported in the literature and in particular, demonstrates significantimprovements in fairness to long RTT connections in the hybrid networkframework.