Experimental Study of Measurement-based Admission Control for Wireless Mesh Networks

The increased deployment of wireless mesh networks (WMNs) should be complemented by a robust resource management scheme that can provide performance guarantees to mission-critical applications. Several admission control schemes have been presented for wireless LANs and wireless ad-hoc networks. However, wireless mesh networks, with static wireless back-bone and multi-hop communication, pose new design challenges. Evaluation of existing admission control schemes has been done primarily via simulations, which often do not have accurate models for capturing interference between adjacent wireless links and nodes. In this paper, we develop light-weight monitoring modules to measure current network/traffic conditions and estimate end-to-end path delay, which is then incorporated in our admission control decision. We utilize a novel layer-2 packet forwarding mechanism, based on the wireless distribution system (WDS) for WMNs. We evaluate our scheme via experiments conducted on a test-bed consisting of IEEE 802.11a-based nodes that form a wireless mesh. Results show that our proposed scheme can provide performance assurance without incurring too much control overhead.