Bidirectional multi-flow MAC protocol for multi-hop underwater acoustic sensor networks

Abstract

Underwater Acoustic Sensor Network (UW-ASN) is a wireless network consisting of spatially distributed autonomous devices using sensors to monitor physical or environmental conditions under water. Due to the atypical characteristics of the physical media in underwater acoustic sensor networks (UW-ASN){mostly because of long propagation delay, low bandwidth and high error rate{several challenges arise while designing a MAC protocol. In this research work, a Bidirectional Multi- Flow MAC protocol (BMF-MAC) for UW-ASN is proposed to handle multi-hop multi- ow data trails in such a way that multiple streams of data transmission proceed concurrently while adapting with varying tra c condition. BMF-MAC supports constitution of multi-hop ows by considering all pending packets in routing layer bu er and all ow setup requests from neighbors when setting up a ow, contrary to other underwater MAC protocols. The proposed MAC introduces a data transmission technique using the bidirectional multi- ow packet method for sending multiple data packets of the same ow in the reverse direction and thus, improve channel utilization. The protocol is aimed to schedule more data transmission over multiple multi-hop ows for rapid distribution of data and reduction of latency. In order to carry out the performance analysis of the proposed BMF-MAC protocol, a mathematical model is derived which includes the equation of energy consumption, throughput, end to end delay and frame error probability. Finally, performance comparison between the proposed BMF-MAC protocol and contemporary CMRT protocol is shown. Our comparison shows that proposed protocol outperforms the contemporary Cascading Multi-hop Reservation and Transmission (CMRT) protocol in terms of throughput, end-to-end delay, and energy consumption.