Coding based multi-hop coordinated reliable data transfer for underwater acoustic networks: Design, implementation and tests

Motivated by some critical observations from field tests, in this paper, we design and implement a Coding based multi-hop Coordinated Reliable Data Transfer (CCRDT) protocol for underwater acoustic networks. CCRDT is based on hop-by-hop reliable data transfer with multi-hop coordination. For the per-hop data transfer, a GF(256) Random Linear Coding scheme and a coding ratio estimation approach are proposed to guarantee the reliability and efficiency of data transfer. In addition, a multi-hop coordination scheme is designed to enable transmission pipelining that allows multiple nodes to transmit simultaneously. By carefully scheduling the transmission of every node, our multi-hop coordination scheme effectively eliminates packet collisions, which further improves the end-to-end throughput. We implement CCRDT on a lab testbed and conducted extensive tests to evaluate its performance. Our results show that CCRDT achieves a higher end-to-end throughput than other existing reliable data transfer protocols which have been implemented in real systems.