HCS: hierarchical cluster-based forwarding scheme for mobile social networks

Clustering has been shown to be a highly effective way to reduce network traffic in mobile ad hoc networks. Many clustering schemes have been proposed. However, none of these schemes can be directly applied to a mobile social network because they are designed for well-connected networks and require timely information sharing among the nodes. In this paper, we propose the hierarchical clustering-based forwarding scheme (HCS), which implements hierarchical clustering on social information. Each node constructs hierarchical clusters based on common neighbor similarity at the end of the warm-up period. The nodes then forward a message to other nodes based on the clustering information and similarity scores. HCS exploits the shortcuts on the path toward the destination node with the help of social similarity and node movement patterns. Experiments were performed on an NS-2 network simulator. The results show that HCS reduces network traffic compared to non-clustering schemes, such as Epidemic, SimBet, PRoPHET, and common neighbor similarity schemes, while maintaining acceptable transmission delay compared to the Wait scheme.