A Distributed End-to-End Reservation Protocol for IEEE 802.11based Wireless Mesh Networks

Abstract—This paper presents an end-to-end reservation pro-tocol for quality-of-service (QoS) support in the medium access control layer of wireless multihop mesh networks. It reserves periodically repeating time slots for QoS-demanding applications, while retaining the distributed coordination function (DCF) for best effort applications. The key features of the new protocol, called “distributed end-to-end allocation of time slots for real-time traffic (DARE), are distributed setup, interference protection, and scheduling of real-time data packets, as well as the repair of broken reservations and the release of unused reservations. A simulation-based performance study compares the delay and throughput of DARE with those of DCF and the priority-based enhanced distributed channel access (EDCA) used in IEEE 802. 11e. In contrast to DCF and EDCA, DARE has a low, nonvarying delay and a constant throughput for each reserved flow. Index Terms—Carrier sense multiple access (CSMA), IEEE 802. 11e, medium access control (MAC), mesh networks, quality-of-ser-vice (QoS), reservation mechanism. I