EURASIP Journal on Wireless Communications and Networking 
Volume 2005 (2005), Issue 5, Pages 757-773
doi:10.1155/WCN.2005.757

An Evaluation of Media-Oriented Rate Selection Algorithm for Multimedia Transmission in MANETs

Mohammad Hossein Manshaei,1 Thierry Turletti,1 and Thomas Guionnet2

 1Planète Project, INRIA, 2004 Route des Lucioles, B.P. 93, Sophia Antipolis Cedex B.P. 93, France
2Temics Project, IRISA-INRIA, Campus de Beaulieu, Rennes Cedex 35042, France
Received 15 June 2004

Abstract

We focus on the optimization of real-time multimedia transmission over 802.11-based ad hoc networks. In particular, we propose a simple and efficient cross-layer mechanism that considers both the channel conditions and characteristics of the media for dynamically selecting the transmission mode. This mechanism called media-oriented rate selection algorithm (MORSA) targets loss-tolerant applications such as VoD that do not require full reliable transmission. We provide an evaluation of this mechanism for MANETs using simulations with NS and analyze the video quality obtained with a fine-grain scalable video encoder based on a motion-compensated spatiotemporal wavelet transform. Our results show that MORSA achieves up to 4 Mbps increase in throughput and that the routing overhead decreases significantly. Transmission of a sample video flow over an 802.11a wireless channel has been evaluated with MORSA. Important improvement is observed in throughput, latency, and jitter while keeping a good level of video quality.