This paper describes the design and prototype implementation of a communication platform aiming to provide voice and video communication in a distributed networking environment. Performance considerations and network characteristics have also been taken into account in order to provide the set of properties dictated by the sensitive nature and the real-time characteristics of the targeted application scenarios. The proposed system has been evaluated both by experimental means as well as subjective tests taken by an extensive number of users. The results show that the proposed platform operates seamlessly in two hops, while in the four hops scenario, audio and video are delivered with marginal distortion. The conducted survey indicates that the user experience in terms of Quality of Service has obtained higher scores in the scenario with the two hops. 1. Introduction Mobile ad hoc networks have received particular attention the last years due to the wide range of applications such as real-time communications including video apart from voice where existing telecommunication infrastructure may fail. The introduction of low-cost wireless technologies and the standardization efforts of the IETF MANET Working Group have been generating renewed interest in research and development of MANETs outside the military field. The advent of new products in both hardware and software has eliminated many of the barriers of the past, enabling the development of integrated platforms providing a wide spectrum of services. In this dynamic and distributed environment it is important to deploy multimedia application and services. This necessitates the deployment of P2P Voice and Video in a large scale, since many users become aware of the abilities of these newly developed architectures and migrate to them. Wireless multihop networks often show great potential, due to some characteristics such as node mobility and extended packet-forwarding ability [1]. Simply applying current peer-to-peer overlay techniques to MANETs is rather undesirable due to node mobility, energy consumption, and lack of infrastructure. Always keeping in mind that the overlay technology needs for power consumption and response time reasons to reflect the underlined physical network topology, wired network control schemes are unable to accommodate a constantly changing peer group where nodes constantly join and quit. An additional issue in the overall idea of this network architecture is peer cooperation. As shown in [2], most topology control algorithms assume that peers are cooperative, which is simply
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