ReDS: Reputation Enhanced Directory Services

Peer-to-peer (P2P) systems are gaining popularity and importance for applications ranging from communications to content delivery over the Internet. Since such systems are inherently formed by a large collection of untrusted peers, their security and reliability can be adversely impacted by malicious peers in the system. In particular, P2P systems must provide a reliable decentralized directory service for locating peers with the desired content and services. If malicious peers are able to subvert directory lookups, the integrity of the system is greatly compromised.

This project advances the state of the art in P2P security and reliability by applying reputation information at the directory level for improved success of subsequent lookups. The new systems will use information from successful and failed lookups, as well as the structure of the peer-to-peer system, to derive reputation information for various peers and estimate the locations of malicious nodes in the system. The project will also include an investigation into mechanisms to limit Sybil attacks, in which attackers attempt to overwhelm the system with malicious peers. The mechanisms will combine the use of social network links and the structure of the P2P system to create a robust identifier space for nodes, thus constraining how many Sybils can be introduced into the system. Through a combination of such techniques, the project will make P2P systems more trustworthy and reliable, directly impacting the millions of users who already make use of such systems today.


Apu Kapadia, Indiana University Bloomington
Matthew Wright, University of Texas at Arlington

PhD Students
Zahid Rahman, Indiana University Bloomington
Mahdi N. Al-Ameen, University of Texas at Arlington
Roman Schlegel, City University of Hong Kong
Ruj Akavipat, Mahidol University, Thailand


Ruj Akavipat, Mahdi N. Al-Ameen, Apu Kapadia, Zahid Rahman, Roman Schlegel, and Matthew Wright,
ReDS: A Framework for Reputation-Enhanced DHTs“,
IEEE Transactions on Parallel and Distributed Systems (IEEE TPDS),
Volume 25, Issue 2, pp. 321–331 (February 2014).
Available as IEEE online preprint, 2013
(bibtex)(ieee preprint)

Ruj Akavipat, Apurv Dhadphale, Apu Kapadia, and Matthew Wright,
ReDS: Reputation for Directory Services in P2P Systems,”
In Proceedings of The ACM Workshop on Insider Threats (WITS ’10),
pp. 47–54, Chicago, IL, October 8, 2010.

Matthew Wright, Apu Kapadia, Mohan Kumar, and Apurv Dhadphale,
ReDS: Reputation for Directory Services in P2P Systems (Extended Abstract),”
In Proceedings of the 6th Annual Cyber Security and Information Intelligence Re- search Workshop (CSIIRW ’10),
Article 71, 4 pages, Oak Ridge, TN, April 21–23, 2010.

Ruj Akavipat, Mahdi N. Al-Ameen, Apu Kapadia, Zahid Rahman, Roman Schlegel, and Matthew Wright,
ReDS: A Framework for Reputation-Enhanced DHTs,”
CoRR arXiv Technical Report arXiv:1209.4867, September 2012.


This material is based upon work supported by the National Science Foundation under Grant Nos. CNS- 1117866, CNS-1115693 and CAREER award (Matthew Wright) number CNS-0954133. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.