QoS Routing in OLSR with Several Classes of Service

Abstract

The optimized link state routing (OLSR) protocol is a proactive link-state protocol for ad-hoc networks. It uses an optimization called multi-point relays (MPRs) to provide an efficient broadcast structure and to reduce the number of link advertisements. Various propositions have been made to enhance the quality of service (QoS) of the routes that OLSR provides, selecting routes according to metrics such as their expected loss rate or throughput. This paper analyzes the existing propositions and finds them lacking. By building upon OLSR's link announcement mechanism, these solutions permit the advertisement of links with non desirable properties and can only support one class of service. We propose ways to improve one of the propositions, QOLSR. Our QOLSR <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> uses MPRs only to create a reliable broadcast structure and employs modified link announcements to increase the number of advertised links