Performance analysis of erasure coding based data transfer in Underwater Acoustic Sensor Networks

This paper investigates the performance of two popular packet level erasure coding approaches, i.e., end-to-end and hop-by-hop, for improving the data transmission reliability in Underwater Acoustic Sensor Networks (UWASNs). In the end-to-end approach, encoding and decoding are performed by the source node and sink node, respectively, while the intermediate nodes just forward the data packets without any processing. In this case, the number of redundant packets to be transmitted by the source (i.e., code rate) is chosen based on packet success probability along the path. On the other hand, the hop-by-hop erasure coding is used to achieve reliability over each hop along the path. In this case, apart from the source node, all the intermediate nodes perform the encoding process and each node adaptively computes the number of redundant packets for the next hop based on the quality of the corresponding hop. We present an analytical model to find the communication overhead, energy consumption and average delay of the multi-hop UWASN under the above erasure coding approaches. The results show that hop-by-hop erasure coding outperforms end-to-end erasure coding.