Relay control for data dissemination of Spontaneous Vehicular Networks

Spontaneous vehicular networks formed by vehicles contribute to safe and comfortable driving by disseminating vehicular movement information. Inter-vehicle communication protocols have been proposed that can provide indirect communications by relaying packets. Although the relay expands the area over which packets can deliver, it generates new communication traffic, hence existing protocols have some mechanism to reduce this traffic, for example the selection of a minimum set of relaying vehicles. However, communication delays increase due to the overhead of the mechanism when the numbers of vehicles increase. In this paper, we propose a relay control protocol for the data dissemination of Spontaneous Vehicular Networks. The protocol controls the relay of each packet, on an as-required basis, in order to adapt to various vehicular communication environments. In addition, the protocol reduces communication traffic by avoiding duplicate relays through a duplicate relay detection algorithm. Furthermore, we evaluate the proposed protocol through experiments and compare it with one of the existing protocols.