Statistical Evaluation of the Behavior of 5-GHz Radio LAN Devices

The goal of this paper is to develop an experimental hardware testbed for verifying the compliance of the medium access mechanism of commercially available Wi-Fi certified units with the IEEE 802.11 standard. The core of this testbed is based on a Universal Software Radio Peripheral (USRP), which is used to capture and downconvert the Wi-Fi frames to the baseband. The data captured by the USRP are used to extract the key medium access parameters of the commercial unit under test (UUT). Our measurement methodology involves a novel compliance metric based on the Kullback-Leibler distance between probability distributions. This metric is in the form of a single scalar, which will hence enable us to rank the UUTs based on their level of compliance. Furthermore, we develop a method based on the harmonized European Standard ETSI EN 301 893 to identify UUTs with noncompliant access mechanisms that tend to monopolize the wireless medium and UUTs for which compliance is an option that deviates from default settings.