Quality-of-service routing in IP networks

Abstract

Multimedia applications such as video-conferencing, telemedicine, HDTV, etc. have very stringent quality-of-service (QoS) demands and require a connection-oriented service. For these applications, a path satisfying their requirements in terms of bandwidth, delay buffer, etc. needs to be found. As conventional IP is based only on hop counts, it is not suitable for multimedia applications. It is clear that, to route requests that have QoS requirements, existing routers should be made QoS aware and the packet forwarding should be based on QoS parameters. Also, protocols like OSPF and RIP must be extended suitably to facilitate QoS The goal of QoS algorithms is to find a loop-less path satisfying a given set of constraints on parameters like bandwidth, delay, etc. The path selection process could return either the entire path to the destination or the best next hop for the request. The first case is called source routing and the second is referred to as routing. In this paper, we propose a new distributed QoS algorithm for unicast flows, which has a very low call establishment overhead. Our algorithm makes use of existing IP protocols such as OSPF and RIP with minimal modifications.