Maximizing remote work in flooding-based peer-to-peer systems

In peer-to-peer (P2P) systems where individual peers must cooperate to process each other’s requests, a useful metric for evaluating the system is how many remote requests are serviced by each peer. In this paper, we apply this remote work metric to study the searching aspect of flooding-based P2P networks such as Gnutella. We study how to maximize the remote work (query) in the entire network by controlling the rate of query injection at each node. In particular, we provide a simple procedure for finding the optimal rate of query injection and prove its optimality. We also show that a simple prefer-high-TTL protocol in which each peer processes only queries with the highest time-to-live (TTL) is optimal.