Does location matter? The efficiency of request propagation based on location in online social networks

Abstract

The centrality metrics such as Closeness and Betweenness in Online Social Network (OSN) determine how much end-to-end delay and queue-load of a node can have as a source or as a destination through Social Routing. Experimentally, we find that nodes with high Out-Closeness centrality in OSN suffer from high end-to-end delay as a target, but not as a source. We show that the cause of this end-to-end delay is that most nodes with high Out-Closeness centrality have low In-Closeness centrality. Moreover, we show that the increase in the local In-Degree centrality will increase the global In-Closeness centrality. We also find that the promised level to increase the In-Closeness centrality of a node is its Friends of Friends-Of-Friends (Level-3). An agent-based Model for Social Routing is proposed and a set of large-scale Google+ Graphs are used. A simulation study is also completed by propagating a set of requests in different societies with different routing schemes and diverse queue disciplines, in order to compare the average end-to-end delays from the source and target perspectives.