Infrastructure-based location estimation in WLAN

This paper focuses on fundamental system deployment aspects of location estimation in 802.11-based wireless networks. We concentrate on adaptable infrastructure-based approaches, where sniffers measure received signal strength from clients to locate them. Our implementation experience and experimental results show that sniffer-based location estimation is feasible and works well provided some important rules are followed. By studying data over a 6-month period, we observe that adaptation of models is necessary for good location estimation, and we show that our techniques enable location estimation with minimal profiling. We also present an intriguing client-assisted approach for location estimation where a client, APs and sniffers collaborate to locale a terminal in enterprise (infrastructure-mode) wireless networks.