Evaluation of Routing Protocols for Video Transmission over MANETs that use Multiple Interfaces and Multiple Channels per node C. Bouras, V. Kapoulas Computer Technology Institute and Press “Diophantus” Patras, Greece, and Computer Engineering and Informatics Dept., University of Patras, Patras, Greece {bouras, kapoulas}@cti.gr A. Gkamas University Ecclesiastical Academy of Vella, Ioannina, Greece gkamas@aeavellas.gr D. Politaki, E. Tsanai Computer Engineering and Informatics Dept., University of Patras, Patras, Greece {politaki, tsanai}@ceid.upatras.gr Abstract—Mobile Ad hoc NETworks (MANETs) are becoming more essential to wireless communications due to growing popularity of mobile devices. Many researchers have committed effort to enhance the Multimedia (video) transmission over MANETs. Various algorithms and mechanisms concerning the optimization of multimedia transmission have been presented. In this work we evaluate the effect of using multiple interfaces and multiple channels per node in the performance of already existing MANET routing protocols during video transmission. The evaluation shows that all routing protocols benefit from using multiple interfaces and multiple channels per node, and the video transmission over MANETs is improved. Keywords: MANETs, Multiple interface, Multiple-channels, Video transmission, Emergency response I. INTRODUCTION Mobile Ad hoc NETworks (MANETs) are becoming more essential to wireless communications due to growing popularity of mobile devices. A node in a MANET could act as a router while having also the possibility of being the sender or receiver of information. Their ability to be self-configured and form a mobile mesh network using wireless links, makes them suitable for a number of cases for which other types of networks cannot fulfill the necessary requirements. MANETs offer the freedom to use mobile devices and move independently of the location of base stations (and outside their coverage) with the help of other network devices. The lack of predefined infrastructure makes them suitable in emergency situations. An important usage scenario of MANETs can be a disaster area or any kind of emergency, in which the fixed infrastructure has been destroyed or is very limited. However, there are certain limitations when we consider MANETs for video transmission applications. First of all, in this dynamic topology routing becomes a very complicated task. The routing protocols that have been developed for MANETs are directly affecting data transmission, and the performance of the relevant applications. Each protocol has its own routing strategy that is used in order to discover a routing path between two ends. The performance varies, depending on network conditions like the density of nodes in a specific area, their speed and direction. It is obvious that the selection of the proper routing protocol for the specific network topology plays a critical role. On the other hand, video transmission applications use UDP as the transport protocol for video packets. Although this is an obvious solution to avoid latency caused by the retransmission and congestion control mechanisms of TCP, it may cause two major problems. The first one has to do with possible bandwidth limitations in which uncontrolled video transmission without any congestion or flow control may lead to increased packet losses. The second issue relates to TCP- friendliness. Under some conditions, uncontrolled video transmission may lead to possible starvation of TCP-based applications running in the same network. A large variety of research has been conducted regarding Multi-Interface Multi-Channel (MIMC) and multi-channel architectures. One of these include the design and implementation of a channel abstraction module [1] that provides the requisite kernel support and implements a hybrid multi-channel protocol using this module. The research results showed that interface switching can be supported with moderate overheads. Another research work focuses on routing in MIMC, proposing an interface assignment strategy that keeps fixed one interface and switch the other interfaces in order to improve capacity with multi-channel networks in case of available interfaces are less than of available channels [2]. Also, in this work, a routing protocol is presented which selects high- 978-1-4799-2084-6/13/$31.00 ©2013 IEEE ICON 2013