Research Letters in Communications
Volume 2008 (2008), Article ID 546184, 4 pages
doi:10.1155/2008/546184
Research Letter

An Analytical Model for Optimum Byte-Level and Packet-Level FEC Assignment Using Buffer Dynamics

Department of Electrical and Computer Engineering, University of Calgary, Calgary, AB, T2N 1N4, Canada

Received 8 January 2008; Accepted 18 March 2008

Academic Editor: Luca De Nardis

Copyright © 2008 Azfar Moid and Abraham O. Fapojuwo. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

This letter presents an analytical model that jointly exploits the buffer dynamics of both the sending and receiving nodes to find the optimum number of byte-level and packet-level forward error correction (FEC) units for real-time multimedia transmission over wireless networks. The proposed analytical model first provides an optimum number of FEC units required at the byte-level, and then chooses the number of FEC units at the packet-level based on current channel and network conditions. The accuracy of the proposed model is dependent on two parameters: the variable deadline-time at the byte-level and fixed round-trip time (RTT) delay at the packet-level. Numerical results demonstrate the effectiveness of the model in reducing the unrecoverable error probability, which is achieved when the byte-level FEC scheme is supplemented by the packet-level FEC scheme.