120 likes | 254 Vues
This paper explores the security vulnerabilities inherent in reputation systems, a vital component of online trust. Key issues addressed include collusion, denial of reputation, whitewashing, and Sybil attacks. It outlines potential use cases in seller reputation, peer-to-peer networks, and key management while proposing a flexible data model for reputation management. The framework aims to evaluate reputation against risk levels and support privacy and identity resolution. The analysis emphasizes the separation of reputation votes from algorithm computations, advocating for a comprehensive understanding of reputation in various contexts.
E N D
Reputation Systems • ENISA paper – a security analysis of reputation systems http://enisarep.notlong.com • Use-cases • Seller reputation • Peer-to-peer • Key management • Anti-spam/IP reputation
Typical security vulnerabilities need to be addressed: • Collusion – voters agree to target a victim • Denial of reputation – campaigns against an individual • Whitewashing (cancelling a bad reputation) • Sybil attacks (creating multiple identities to vote – e.g. Ebay 1 cent items voted on by seller)
OASIS - ORMS • Develop scenarios for reputation management • Reputation of individuals, business partners, services processes, possibly even data • Develop reference/standard model • Flexible reputation data model • Framework and protocol/s for exchanging and porting reputation data • Evaluation algorithms for mapping reputation to risk / risk levels • Support for privacy, multiple identities, identity resolution
Reputation is an aggregation of opinions about an assertion Assertion – Bob is a bad husband Assertion – Bob is a good laptop seller
The anatomy of reputation – personal view Assertion – Bob is a good laptop seller
Reputation Thoughts • Reputation votes should be separated from the algorithm used to compute it • Mean score • 2nd order reputation • Reputation Context => Same vote set can be interpreted differently • If reputation is an aggregated opinion about an assertion – why not integrate with SAML?
Reputation Thoughts • Model must allow for so-called 2nd order reputations (scores which take into account the reputation of the voter) • Rating context should be taken into account – time/date, authentication method/token etc...