Cooperative data dissemination via roadside WLANs

Data dissemination services embrace a wide variety of telematic applications where data packets are generated at a remote server in the Internet and destined to a group of nomadic users such as vehicle passengers and pedestrians. The quality of a data dissemination service is highly dependent on the availability of network infrastructures in terms of the access points. In this article, we investigate the utilization of roadside wireless local area networks (RS-WLANs) as a network infrastructure for data dissemination. A two-level cooperative data dissemination approach is presented. With the network-level cooperation, the resources in the RS-WLANs are used to facilitate the data dissemination services for the nomadic users. The packet-level cooperation is exploited to improve the packet transmission rate to a nomadic user. Various techniques for the two levels of cooperation are discussed. A case study is presented to evaluate the performance of the data dissemination approach.