RE-MAC: A Hybrid MAC Protocol for Underwater Multimedia Communication System

In this article, we propose a reliable and efficient medium access control (MAC) protocol, RE-MAC, for resource-constraint underwater acoustic multimedia communication systems. RE-MAC achieves scalability by utilizing a hybrid MAC protocol smartly, which takes advantage of contention, reservation, and null data packet (NDP) based channel access mechanisms. The proposed scheme achieves multihop communication and synchronization for video streaming using a transmission opportunity (TXOP) based efficient channel access mechanism at the access point (AP) and relay nodes. TXOP time has been utilized by relay and AP for sending stream of frames with low overhead. To improve the efficiency in multihop communication, RE-MAC finds an optimal frame duration for relays and AP. RE-MAC efficiently places the NDP mechanism replacing traditional ACK-based control packet exchange. We incorporate the TXOP in AP and relay nodes for multimedia streaming and sleep mode for stations. Further, the video compression technique gives the efficiency of our system to improve the transmission of multimedia data. Our proposed schemes help communicate multimedia data without compromising the quality of service. We have demonstrated our proposed scheme experimentally in a prototype. After that, a simulation-based detailed performance analysis is provided to see the scalability of the proposed scheme. Compared to the existing state-of-the-art solutions, RE-MAC significantly delivers the throughput, energy consumption, delay, and packet loss.