Retransmission scheme for intra-session linear network coding in wireless networks

Abstract

In this paper, we study the problem of feedback mechanism design for packet retransmission in lossy wireless networks where nodes employ intra-session random linear network coding (RLNC). Using intra-session RLNC, intermediate nodes transmit coded packets by combining the packets of various flows until they receive acknowledgements. A delayed acknowledgment can increase the power consumption while an early one interrupts the decoding process at the sink. First, we determine the earliest time at which an intermediate node can stop transmission of a particular flow. We propose a novel link-by-link feedback mechanism in which every intermediate node generates feedback control packet for its upstream nodes. We propose three different types of end-to-end feedback mechanisms while the sink is responsible in generating feedbacks. The results show the performance gain of using intra-session network coding in terms of power consumption at the cost of higher delay.