A Survey of Trust Evaluation Methods (Supervisor: Yan Wang) Name:Erden Sacan Student ID: Unit:ITEC810

A Survey of Trust Evaluation Methods 2 Agenda Definition of Trust and an example Four major areas in application of trust evaluation methods Findings of research & conclusion

A Survey of Trust Evaluation Methods 3 What is Trust? “A relationship of reliance dependent on what other people say.” “An agent’s estimate of how likely another is to fulfil its commitments “

A Survey of Trust Evaluation Methods 4 Trust Evaluation Methods Survey Various ways to measure trust in computer applications. – How to choose? – Which one is the best? – Is there a “best” Collect and classify trust evaluation methods Analyse and find; – Strenghts – Weaknessess – Similarities – General requirements of different applications

A Survey of Trust Evaluation Methods 5 An Example!

A Survey of Trust Evaluation Methods 6 User Feedback Ratings

A Survey of Trust Evaluation Methods 7 eBay summary Buyers and sellers in can rate each other Negative, neutral or positive ratings User Rating= positive feedback count – negative feedback Feedback ratings summary is displayed on user’s profile Too simple - But it works! (Ref:

A Survey of Trust Evaluation Methods 8 Major applications E-commerce Peer-to-peer networks – Gnutella, BitTorrent Service-oriented computing – Distributed software development – Multi-supplier supply chains for web services

A Survey of Trust Evaluation Methods 9 E-commerce Needs centralised management Binary rankings are not enough – Negative ratings are very uncommon Needs additional parameters of trust: – Customer satisfaction level – Number of transactions by a party – The amounts of transactions – Timely delivery of goods

A Survey of Trust Evaluation Methods 10 P2P Networks P2P Information sharing networks – Open to public – Big scale – No central authority Mostly requesting party doesn’t know target (serving) party

A Survey of Trust Evaluation Methods 11 P2P Networks – Trust Systems Binary rankings generally work – File transfer – (successful or unsuccessful) Self-policing (Not centralised) Anonymity (Hide user IDs) No profit for newcomers Minimal overhead Parties are not always online

A Survey of Trust Evaluation Methods 12 Service Oriented Computing (SOC) Service Oriented Computing: – Many providers offering services over the network – Distributed software development Fast, cheap, highly reusable services (coding and orchestration of code) – Also adopted by other sectors Travel agencies(car rental, hotel, airline, insurance services)

A Survey of Trust Evaluation Methods 13 Service Oriented Computing (SOC) – How to use trust?

A Survey of Trust Evaluation Methods 14 Service Oriented Computing (SOC) – Trust Methods SOC Trust Evaluation Methods: – Many domains – many rules – trust system needs to be flexible (event driven) – System should consider; Quality of Service Timeliness – Use multiple feedback sources (memberhips, certificates) – Needs good filtering of malicious and fake entries

A Survey of Trust Evaluation Methods 15 Conclusion  “All-in-one-best trust mechanism” – Not possible! (At least for now) Every area has different requirements Some needs a simple approach Some needs many parameters All of them need to prevent malicious entries

A Survey of Trust Evaluation Methods 16 Thank You... – Today we have talked about; What trust is Trust evaluation methods in different applications Trust evaluation requirements of applications.