Abstract
In vehicular sensor networks (VSNs), an increase in the density of the vehicles on road and route jamming in the network causes delay in receiving the emergency alerts, which results in overall system performance degradation. In order to address this issue in VSNs deployed in dense urban regions, in this paper, we propose collaborative learning automata-based routing algorithm for sending information to the intended destination with minimum delay and maximum throughput. The learning automata (LA) stationed at the nearest access points (APs) in the network learn from their past experience and make routing decisions quickly. The proposed strategy consists of dividing the whole region into different clusters, based on which an optimized path is selected using collaborative LA having input parameters as vehicle density, distance from the nearest service unit, and delay. A theoretical expression for density estimation is derived, which is used for the selection of the "best" path by LA. The performance of the proposed scheme is evaluated with respect to metrics such as packet delivery delay (network delay), packet delivery ratio with varying node (vehicle) speed, transmission range, density of vehicle, and number of road side units/APs). The results obtained show that the proposed scheme performs better than the benchmark chosen in this study, as there is a 30% reduction in network delay and a 20% increase in packet delivery ratio.