Designing a Quality of Service for mobile Ad Hoc Networks carrying multimedia traffic.

Abstract

Multimedia transmission over communication networks has been growing rapidly with respect to the number of users and the amount and type of traffic. Wireless communications are a fast emerging technology and have become an essential feature of everyday life. Not only are computer networks becoming mobile, but each device is eventually having one or several wireless interfaces (e.g. laptops, cameras, phones etc.).Simultaneously, multimedia is having an equivalent growth, and is now constituting a large part of the traffic flowing through the wireless network through increased use in both the commercial as well as the social arena. These multimedia applications such as voice over IP, video conferencing, and video-on-demand, generate traffic with characteristics that differ significantly from the traffic generated by data applications, and they have more strict delay and packet loss requirements. Guaranteeing those requirements in wireless environments is very challenging because wireless links have variable characteristics especially through their mobile and ad hoc nature. To deal with this problem, many wireless communication standards have been defined enhancing the Quality of Service (QoS) of the whole system but do not specifically enhance multimedia traffic on its own. In this paper we propose mechanisms for modifying the existing QoS frameworks to include traffic prioritization, with multimedia traffic as the highest priority and to include different dropping probabilities for each class and congestion avoidance. We first study existing QoS frameworks then modify an existing framework (ASAP) to include traffic classification and bandwidth adaptation.