Passive neighbor discovery with social recognition for mobile ad hoc social networking applications

Neighbor discovery is the cornerstone of the mobile social applications over mobile ad hoc networks. Most current neighbor discovery protocols adopt a carefully designed wake-up/sleep schedule. However, a well-designed wake-up/sleep neighbor discovery schedule still might miss those neighbor nodes in the sleep state or discover undesirable neighbors with different purposes. Either results in inevitable discovery latency and unnecessary energy consumption. In this paper, we propose a flexible neighbor discovery protocol with social recognition under a passive discovery framework. In this framework, each mobile device is equipped with a wake-up radio. When a mobile node, called sponsor node, launches a neighbor detection, it will broadcast a wake-up radio signal before the hello message. Within a certain distance, the node will be triggered by its wake-up radio for a hello message, which is integrated with the social information. Furthermore, a flexible self-adjustment strategy is designed for the sponsor node to improve discovery-efficiency. Our protocol shows higher efficiency in both discovery latency and energy consumption than the traditional deterministic neighbor discovery protocols in the simulation.