Data Dissemination Techniques and Publish/Subscribe Architecture in Vehicular Adhoc Networks

Vehicular Adhoc network (VANET) is a subset of Mobile Adhoc Network (MANET). It integrates mobile connectivity protocols to expedite data transfer between vehicles as well as between roadside equipment and available traffic in the network. There are main two types of communication carried out in VANET i.e. Vehicle to Vehicle (V2V) and Vehicle to Infrastructure (V2I). There is a large number of interesting applications for vehicular networks: traffic information dissemination, warnings, free parking spots finders, fuel prices advertising, etc. The Publish/ Subscribe (P/S) communication paradigm enables the application developers to easily design flexible notification systems. Furthermore, it enables the drivers/vehicles to indicate their interests about certain types of notifications (e.g. receive warnings concerning traffic jams only within 1km from the vehicle’s route). And finally, P/S is an asynchronous communication protocol (spatial and temporal decoupling) that is suitable for the delay-tolerant network conditions. In the section I, brief introduction to Vehicular Adhoc Network is described. In section II, VANET applications and characteristics are discussed. In section III, various Data Dissemination techniques are explained in detail. In section IV, Publish/Subscribe architecture is explained and information flow in the network is described.