Reducing the Channel Scanning Latency for Intermittently Connected IEEE 802.11 Networks in Vehicular Environments

In an intermittently connected environment, access points are sparsely distributed throughout an area. As mobile users travel along the roadway, they can opportunistically connect, albeit temporarily, to roadside 802.11 (Wi-Fi) APs for Internet access. Networking characteristics of vehicular opportunistic Internet access in an intermittently connected environment face numerous challenges, such as short periods of connectivity and unpredictable connection times. To meet these challenges, we propose an access point report (APR) protocol where mobile stations opportunistically collaborate by broadcasting an APR to other mobile stations to fully utilize the short-lived connection periods. APR can optimize the use of short connection periods by minimizing the scanning delay and also act as a hint that enables mobile users to predict when connection can be established.