Are You Moved by Your Social Network Application

This paper studies a Bluetooth-based mobile social network application deployed among a group of 28 participants col-lected during a computer communication conference. We compare the social graph containing friends, as defined by participants, to the contact graph, that is the temporal net-work created by opportunistic contacts as owners of devices move and come into communication range. Our contribu-tion is twofold: First, we prove that most properties of nodes, links, and paths correlate among the social and contact graphs. Second, we study how the structure of the social graph helps building forwarding paths in the temporal network, allow-ing two nodes to communicate over time using opportunis-tic contacts and intermediate nodes. Efficient paths can be built using only pairs of nodes that are close in a social sense, making opportunistic forwarding compliant with the requirement of social network application. 1