A Blind Message Dissemination Method for OUSN using Unmanned Underwater Vehicles

Opportunistic Underwater Sensor Network (OUSN) comprised of Unmanned Underwater Vehicles (UUV) has been deployed for the surveillance of various underwater events, and in some military environments an OUSN could be invaded by some underwater spy-robots termed eavesdroppers. Typically, the eavesdroppers move around OUSN nodes and eavesdrop on their communication channels silently. Thus, the eavesdroppers are hard to be perceived by the nodes, which implies that the nodes are blind to the eavesdroppers. The nodes probably disseminate the held data messages while they are blithely unaware of the adjacent eavesdroppers, and the eavesdroppers could capture these data messages. To reduce the theft ratio of data messages and guarantee the required delivery ratio in a storage-limited OUSN, a propagation model of data messages is formulated to analyse the proportion variation of message holders. Based on this model, the reduction of theft ratio is specially investigated to obtain the appropriate disseminating probabilities, storing probabilities, and discarding probabilities of the nodes with different indegrees. In the proposed Blind Message Dissemination Method (BMDM), the data messages are disseminated, stored, and discarded according to these probabilities. Simulation results demonstrate that BMDM can reduce the theft ratio and guarantee the required delivery ratio in a storage-limited OUSN effectively.