1. A Trust Aggregation Portal
Supervisor:
Prof. Gihan Dias 128202E – A.G.E.A. Abeynayake

2. Social Identity & Trust
• What is Social Identity?
– Layman View
– Cyberspace
• Where does Trust
fits in?
Image Courtesy of: Social Identity Report at http://www.veechi.com/sir.html

3. Problem Definition
• Numerous interconnections between individuals and
Organizations
– Multiple Identities
• Enormous social networking sites
– Overlapping Content
– Non-overlapping Content
• Isolated nature of individual systems
– Has there own Recommendation system
– Personal Profile information
– Not Disclosed to other systems

4. A Step Ahead...
• A “Trust mark” for Individuals
 Feedback by Friends
 Day-to-Day Activities
 Context Information
Image Courtesy of: Social Identity Report at http://www.veechi.com/sir.html

5. Literature Review – Area of Concern
• Study about NSTIC
– National Strategy for Trusted Identities in
Cyberspace
• Collecting Aggregating User Data
– Extraction Methods
– Current Systems
• Trust and Reputation Models
– Existing models for Trust Scoring

6. NSTIC Study
• NSTIC Addresses two central problems [1]
– Passwords are inconvenient and insecure
– Individuals are unable to prove their true identity
online for significant transactions
• Key Operational Roles
– subjects
– relying parties
– identity providers
– attribute providers
– accreditation authorities

7. Identity Ecosystem [2]
• NSTIC provides a framework for individuals
and organizations to utilize
secure, efficient, easy-to-use
• and interoperable identity solutions to access
online services in a manner that promotes
• confidence, privacy, choice and innovation.

8. Image courtesy: www.ftc.gov/bcp/workshops/.../personalDataEcosystem.pdf

9. Collection and Aggregation of data
• Prying Data out of a Social Network [3]
presents Methods Of Extracting Data
– Public Listings
– Facebook and LinkedIn APIs
– Facebook Graph API
– Scraping Facebook UI

10. Collection and Aggregation of data
• Crawling Social Networks [4]
– crawled these user data in a breadth-first fashion
– used a queue data structure
– Stored in MySQL database using a simple schema

11. Trust and Reputation
• Trust Classes [5] - According to Grandison &
Sloman's classication
• Classification of trust and reputation measures
Specific General
Subjective Survey eBay, voting
questionnaires
Objective Product tests Synthesised general
score from
product tests, D&B
rating

12. Trust and Reputation
• Reputation Network Architectures [5]
– Centralised Reputation Systems
– Distributed Reputation Systems
• Classification of Reputation Systems [6]
– Flat reputation systems
– Recursively weighting reputation system
– Personalized reputation system with trust anchor

13. Trust and Reputation
• Algorithms and Methods for Measurement [7]
[8]
– Collaborative filtering and Collaborative
Sanctioning
– Bayesian Networks
– Fuzzy Decision Trees
– Boosting algorithms

14. References
[1] National Institute Of Standards And Technology. “Recommendations For
Establishing An Identity Ecosystem Governance Structure”. White
House.Department of Commerce. Available at:
http://www.nist.gov/nstic/2012-nstic-governance-recs.pdf
[2] NSTIC. “Enhancing Online Choice, Efficiency, Security, and Privacy”.
Available at:
http://www.whitehouse.gov/sites/default/files/rss_viewer/NSTICstrategy_
041511.pdf
[3] Joseph Bonneau, Jonathan Anderson, George Danezis. "Prying Data out of
a Social Network", ASONAM '09 Proceedings of the International
Conference on Advances in Social Network Analysis and Mining, 2009, pp.
249-254
[4] D. H. Chau, S. Pandit, S. Wang, and C. Faloutsos, “Parallel Crawling for
Online Social Networks,” in WWW ’07: Proceedings of the 16th
international conference on World Wide Web, 2007, pp. 1283–1284.

15. References
[5]B. Krishnamurthy and C. E. Wills, “Characterizing Privacy in Online Social
Networks,” in WOSN: Workshop on Online Social Networks, 2008, pp. 37 –
42.
[6] W. Xu, X. Zhou, and L. Li, “Inferring Privacy Information via Social
Relations,” International Conference on Data Engineering, 2008.
[7] A. Gutscher, J. Heesen and O. Siemoneit, “Possibilities and Limitations of
Modeling Trust and Reputation,” Proc. CEUR Workshop, 2008.
[8]Audun Jøsang, Roslan Ismail, and Colin Boyd. 2007. A survey of trust and
reputation systems for online service provision. Decis. Support Syst. 43, 2
(March 2007), 618-644.