Group Management in P2P Networks

Groups are both, a social phenomenon inherent to the human nature and a widely used structure in distributed systems. Recently, the Web 2.0 trend has begun to unite both aspects. Social networks provide their users with simple means to create, modify, join, and leave groups dynamically. Popular applications such as chat rooms and multi-player online games require social group structures. The same holds true for many e-science applications. But despite their growing importance, the structure of social groups has not yet been studied with respect to peer-to-peer or cloud computing systems. In this paper, we analyze the requirement structure that the different types of social groups induce in distributed systems. In particular, we focus on fully decentralized peer-to-peer systems. First, we formalize the requirements using results from field studies in social networks. Then we classify the various group management models by considering their differences in group creation and management. We also discuss scalability, maintainability, security issues and privacy guarantees of the different group models.