GPS-Based Replica Deletion Scheme with Anti-Packet Distribution for Vehicular Networks

In vehicular networks, since reliable end-to-end paths between data source and destination seldom exist, replication-based routing protocols are widely used to increase the delivery ratio and reduce the transfer delay. However, after a data message is delivered, its replicas still exist and greatly waste network resources, such as transmission bandwidth and storage spaces. In mobile multimedia communications, the large size of multimedia data greatly aggravates this situation. In this paper, we propose a GPS-based replica deletion scheme with anti-packet distribution for vehicular networks, namely RAD. It utilizes vehicle-to-vehicle and vehicle-to-roadside-unit communications to remove redundant data replicas by a certain number of anti-packets. A roadside unit at each crossing distributes its collected anti-packets to nearby vehicles moving for different directions according to the geographical locations of the to-be-deleted targets. This distribution increases the delivery probability of these anti-packets. Experiment results in a real taxi network show that, compared with others, RAD accelerates replica deletion with less extra overhead.