Reliability Gain of Network Coding in Lossy Wireless Networks

Abstract

Abstract-The capacity gain of network coding has been extensively studied in wired and wireless networks. Recently, it has been shown that network coding improves network reliability by reducing the number of packet retransmissions in lossy networks. However, the extent of the reliability benefit of network coding is not known. This paper quantifies the reliability gain of network coding for reliable multicasting in wireless networks, where network coding is most promising. We define the expected number of transmissions per packet as the performance metric for reliability and derive analytical expressions characterizing the performance of network coding. We also analyze the performance of reliability mechanisms based on rateless codes and automatic repeat request (ARQ), and compare them with network coding. We first study network coding performance in an access point model, where an access point broadcasts packets to a group of K receivers over lossy wireless channels. We show that the expected number of transmissions using ARQ, compared to network coding, scales as Θ(log K) as the number of receivers becomes large. We then use the access point model as a building block to study reliable multicast in a tree topology. In addition to scaling results, we derive expressions for the expected number of transmissions for finite multicast groups as well. Our results show that network coding significantly reduces the number of retransmissions in lossy networks compared to an ARQ scheme. However, rateless coding achieves asymptotic performance results similar to that of network coding.

Utility-Based Joint Routing, Network Coding, and Power Control for Wireless Ad Hoc Networks

“…It has been shown that NC offers exciting benefits in terms of throughput, reliability, cost, and delay in wireless networks [15][16][17][18]. Specifically, the reliability gain of NC was studied recently in [7,19,20]. The work in [19] confirmed that NC could increase the reliability by reducing the number of transmissions in unicast communication.…”

“…After receiving the required number of encoded packets, a receiver can decode out the original packets. Recent work [7] shows that NC can improve reliability by reducing the number of packet retransmissions in wireless lossy networks.…”

Opportunistic wireless network coding with relay node selection

“…For throughput, network coding technique can take advantages of bottleneck effect of data at the intermediate node in wireless communication to improve the system throughput [3]. Ghaderi et al [4] have shown that there are reliability benefits by applying network coding technique in their system. Li et al [5] show that the maximum achievable rate can be achieved by linearly combining input packets at an intermediate node.…”

Analysis and design of multi-session network coding

“…The potential advantages of network coding over routing include the enhancement in network throughput [4][5][6], reliability [7][8][9], energy efficiency [10,11], security [12] and others [13][14][15][16]. Due to these promising benefits, network coding has found a wide range of applications in ad hoc networks [17][18][19], wireless mesh networks [6,[20][21][22][23], peer-to-peer communication systems [24][25][26] and distributed data storage [27].…”

“…One commonly used field size for RLNC is 28 . Here, a small field size is used for illustration purposes.…”