DCMP: A Distributed Cycle Minimization Protocol for Peer-to-Peer Networks

Broadcast-based peer-to-peer (P2P) networks, including flat (for example, Gnutella) and two-layer superpeer implementations (for example, Kazaa), are extremely popular nowadays due to their simplicity, ease of deployment, and versatility. The unstructured network topology, however, contains many cyclic paths, which introduce numerous duplicate messages in the system. Although such messages can be identified and ignored, they still consume a large proportion of the bandwidth and other resources, causing bottlenecks in the entire network. In this paper, we describe the distributed cycle minimization protocol (DCMP), a dynamic fully decentralized protocol that significantly reduces the duplicate messages by eliminating unnecessary cycles. As queries are transmitted through the peers, DCMP identifies the problematic paths and attempts to break the cycles while maintaining the connectivity of the network. In order to preserve the fault resilience and load balancing properties of unstructured P2P systems, DCMP avoids creating a hierarchical organization. Instead, it applies cycle elimination symmetrically around some powerful peers to keep the average path length small. The overall structure is constructed fast with very low overhead. With the information collected during this process, distributed maintenance is performed efficiently even if peers quit the system without notification. The experimental results from our simulator and the prototype implementation on PlanetLab confirm that DCMP significantly improves the scalability of unstructured P2P systems without sacrificing their desirable properties. Moreover, due to its simplicity, DCMP can be easily implemented in various existing P2P systems and is orthogonal to the search algorithms.

[1]  Fabián E. Bustamante,et al.  Friendships that Last: Peer Lifespan and its Role in P2P Protocols , 2003, WCW.

[2]  Nicolas Christin,et al.  Content availability, pollution and poisoning in file sharing peer-to-peer networks , 2005, EC '05.

[3]  Scott Shenker,et al.  Making gnutella-like P2P systems scalable , 2003, SIGCOMM '03.

[4]  Panos Kalnis,et al.  A general framework for searching in distributed data repositories , 2003, Proceedings International Parallel and Distributed Processing Symposium.

[5]  Li Xiao,et al.  A distributed approach to solving overlay mismatching problem , 2004, 24th International Conference on Distributed Computing Systems, 2004. Proceedings..

[6]  Atul Singh,et al.  Eclipse Attacks on Overlay Networks: Threats and Defenses , 2006, Proceedings IEEE INFOCOM 2006. 25TH IEEE International Conference on Computer Communications.

[7]  Beng Chin Ooi,et al.  An adaptive peer-to-peer network for distributed caching of OLAP results , 2002, SIGMOD '02.

[8]  Li Xiao,et al.  Location awareness in unstructured peer-to-peer systems , 2005, IEEE Transactions on Parallel and Distributed Systems.

[9]  Edith Cohen,et al.  Search and replication in unstructured peer-to-peer networks , 2002, ICS '02.

[10]  Bruce M. Maggs,et al.  Efficient content location using interest-based locality in peer-to-peer systems , 2003, IEEE INFOCOM 2003. Twenty-second Annual Joint Conference of the IEEE Computer and Communications Societies (IEEE Cat. No.03CH37428).

[11]  Hector Garcia-Molina,et al.  Query-flood DoS attacks in gnutella , 2002, CCS '02.

[12]  Ian T. Foster,et al.  Mapping the Gnutella Network , 2002, IEEE Internet Comput..

[13]  Christos Gkantsidis,et al.  Random walks in peer-to-peer networks , 2004, IEEE INFOCOM 2004.

[14]  David R. Karger,et al.  Chord: a scalable peer-to-peer lookup protocol for internet applications , 2003, TNET.

[15]  Mark Handley,et al.  A scalable content-addressable network , 2001, SIGCOMM '01.

[16]  Christopher R. Palmer,et al.  Generating network topologies that obey power laws , 2000, Globecom '00 - IEEE. Global Telecommunications Conference. Conference Record (Cat. No.00CH37137).

[17]  Stefan Saroiu,et al.  A Measurement Study of Peer-to-Peer File Sharing Systems , 2001 .

[18]  Hector Garcia-Molina,et al.  Designing a super-peer network , 2003, Proceedings 19th International Conference on Data Engineering (Cat. No.03CH37405).

[19]  Hector Garcia-Molina,et al.  Improving search in peer-to-peer networks , 2002, Proceedings 22nd International Conference on Distributed Computing Systems.