ChitChat: An Effective Message Delivery Method in Sparse Pocket-Switched Networks

The ubiquitous adoption of portable smart devices has enabled a new way of communication via Pocket Switched Networks (PSN), whereby messages are routed by personal devices inside the pockets of ever-moving people. PSNs provide opportunities for various interesting applications such as location based social networking, geolocal advertising, and military missions in active battlefields where the central communication tower is unavailable. One key challenge of the successful roll-out of PSN applications is the difficulty of achieving high message delivery ratio due to the dynamic nature of moving people and spatial-temporal sparsity in such networks. In this paper, we propose a novel message routing approach, called ChitChat, which exploits users' direct and transient social interests via discriminatory gossiping to penetrate messages deeper into the network. Our approach enables message carriers to make opportunistic and distributed routing decisions based on the likelihood a potential message receiver will meet individuals that have a high chance to forward the message to the destination. Our experimental results have demonstrated that our approach achieves higher delivery ratios against the two more recent state-of-the-art algorithms, while maintaining a lower communication overhead against flooding and reducing the amount of time messages remain idlein buffers.