QoS for real-time reliable multicasting in wireless multi-hop networks using a Generation-Based Network Coding

Most of the works on Generation-Based Network Coding (GBNC) consider a fixed generation size. A large generation size maximizes the Network Coding benefits but leads to a long delay while a small generation size reduces the delay but decreases the throughput. This paper presents the DYnamic GEneration Size (DYGES) approach. Our network-aware method adjusts the generation size according to the network variations (network size, congestion, losses) for multicast flows to keep the delay steady. Since Network Coding and redundancy cope with data packet loss, we propose an enhancement of DYGES with ACK recovery. This method, named RDYGES, uses the opportunistic listening feature of nodes to recover the lost ACK. Our goal is to guarantee a Quality of Service (QoS) in terms of delay. The simulation results show the accuracy of our approach. 2013 Elsevier B.V. All rights reserved.