Message management protocol for persistent geocast routing

摘要

A system and method are provided for providing a log to maintain a persistent alert message in a region of interest. The protocol begins its operation when a dangerous condition is detected by a vehicle. The detecting vehicle uses a multi-hop geocasting broadcasting process to transmit a warning message to other vehicles in the region in question. When the vehicles in the region in question receive the warning message, they are prevented from retransmitting the message for a first predetermined period of time. After the first predetermined period of time has elapsed, a contention timing process is used to determine which of those vehicles will retransmit the message to other vehicles entering the region in question. This process of retransmission continues until a second predetermined period of time elapses, the message then not being retransmitted.