Title :
WizNet: A ZigBee-based sensor system for distributed wireless LAN performance monitoring
Author :
Ruogu Zhou ; Guoliang Xing ; Xunteng Xu ; Jianping Wang ; Lin Gu
Author_Institution :
Michigan State Univ., East Lansing, MI, USA
Abstract :
802.11-based wireless LANs (WLANs) have become an important communication infrastructure for today´s pervasive computing applications. Nevertheless, WLAN users often experience various performance issues such as highly variable signal quality. To diagnose such transient service degradations and plan for future network upgrades, it is essential to closely monitor the performance of a WLAN and collect user statistics. This paper proposes a new WLAN performance monitoring approach motivated by the fact that many low-power wireless technologies such as ZigBee and Bluetooth co-exist with WLAN in the same open radio spectrum and are capable of sensing Received Signal Strength (RSS) of 802.11 transmissions. We have developed a ZigBee-based WLAN monitoring system called WizNet. Powered by batteries, ZigBee sensors of WizNet can be deployed in large quantities to monitor the spatial performance of a WLAN in long periods of time. By adopting digital signal processing techniques, WizNet automatically identifies 802.11 signals from ZigBee RSS measurements and associates them with wireless access points. To ensure the monitoring fidelity, WizNet accounts for the significant differences in ZigBee and WLAN radios, such as bandwidth and susceptibility to multipath and frequency-selective fading. A simple yet accurate linear estimator derived from a signal propagation model is used to infer the access points´ signal to noise ratio (SNR). Moreover, WizNet can measure the congestion level of the channel and detect rogue APs. WizNet can also collect WLAN client statistics and classify device models based on RSS signatures of 802.11 access point scans. We have implemented WizNet in TinyOS 2.x and extensively evaluated its performance on a wireless testbed. Our results over a period of 140 hours show that WizNet can accurately capture the spatial and temporal performance variability of a large-scale production WLAN.
Keywords :
Zigbee; fading channels; multipath channels; radiotelemetry; ubiquitous computing; wireless LAN; wireless sensor networks; 802.11-based wireless LAN; RSS signatures; TinyOS; WLAN client statistics; WLAN performance monitoring approach; WLAN radios; WLAN users; WizNet; Zigbee RSS measurements; Zigbee-based sensor system; access point SNR; access point signal to noise ratio; communication infrastructure; digital signal processing techniques; distributed wireless LAN performance monitoring; frequency-selective fading; large-scale production WLAN; low-power wireless technologies; multipath fading; pervasive computing applications; received signal strength; signal propagation model; wireless access points; IEEE 802.11 Standards; Monitoring; Signal to noise ratio; Wireless LAN; Wireless communication; Wireless sensor networks; Zigbee;
Conference_Titel :
Pervasive Computing and Communications (PerCom), 2013 IEEE International Conference on
Conference_Location :
San Diego, CA
Print_ISBN :
978-1-4673-4573-6
Electronic_ISBN :
978-1-4673-4574-3
DOI :
10.1109/PerCom.2013.6526722