DARE: DoF-Aided Random Encoding for Network Coding over Lossy Line Networks

© 1997-2012 IEEE. In this letter, we propose a practical (low delay and low overhead) and simple (low complexity) network coding strategy for real time transmission over lossy line networks. We propose Systematic Random Coding (SRC) as outer code, which is performed at the transmitter node. The inner code is a combination of random coding and repetition coding (over innovative packets only) performed at the intermediate nodes. Our solution, which we term DARE (DoF Aided Random Encoding) minimizes overall processing complexity, delay, and overhead w.r.t. state-of-the art network coding proposals. We derive a theoretical lower bound on the achievable rates of DARE and validate it with simulations. Our simulation results show that DARE guarantees maximum achievable rates (up to 103.36%) higher than those achieved by routing. Furthermore, enabling DARE to be adaptive to the channel conditions allows trade off, whether to encode or not, since by not encoding (e.g., in some cases) up to 50% complexity reduction can be obtained with up to 0.2% loss in the maximum achievable rates.