A modular access gateway for managing intermittent connectivity in vehicular communications

The Drive-thru Internet architecture allows exploiting intermittent connectivity by temporarily connecting to IEEE 802.11 WLAN access points at the roadside from moving vehicles. This poses numerous challenges to a mobile user’s equipment: extreme networking characteristics such as short periods of connectivity, unpredictable disconnection times, and vastly varying transmission characteristics. Heterogeneous WLAN hotspot installations may also require different authentication mechanisms and credentials. We have designed a mobile access gateway to deal with these issues on behalf of a user (group) in a moving vehicle and provide usable connectivity for applications without requiring manual operation. The gateway maximises the use of short connectivity periods by detecting network access providing signalling functions for local application processes. It also allows using dedicated radio equipment to prolong connectivity periods. Finally, in selected multi-user scenarios, further performance improvements are conceivable by sharing (non-confidential) information across users and applications.