An Efficient Reservation-based MAC Protocol for IEEE802.11s Mesh Networks

摘要

Wireless mesh networking based on IEEE 802.11 wireless local area network (WLAN) has been actively explored in recent years. The IEEE 802.11s amendment specified a standard for WLAN mesh networks by adding functionalities necessary for topology formation and discovery, path selection, interworking, and security. Regarding medium access control, the mandatory protocol is EDCA while an optional protocol, called Mesh Deterministic Access (MDA), was specified with the aim of enhancing medium access efficiency. Both the EDCA and MDA protocols suffer from the inefficiency of the underlying CSMA/CA scheme to exploit spatial reuse of wireless spectrum. Moreover, they provide prioritized channel access at best. In this paper, we propose a MAC protocol, called Interference-aware Distributed Reservation Protocol (IDRP), which aims at enhancing spatial reuse of wireless spectrum while ensuring packet reception quality, as specified by a required SINR level, over a reserved wireless link. IDRP is based on time-division multiple access / time-division duplex (TDMA/TDD) technology and operates under distributed control. Simulation results are provided to verify the efficiency of IDRP in exploiting link diversity.