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Seminar:  On the Foundations of Trust in Networks of Humans and Computers

Date:September 24, 2012 
Talk Title:On the Foundations of Trust in Networks of Humans and Computers
Speaker:Virgil Gligor
Time & Location:12:00pm - 1:00pm
CIC Building, Pittsburgh


A general theory of trust which focuses on the establishment of new trust relations where none were possible before would help create new economic opportunities. New trust relations would increase the pool of services available to users, remove cooperation barriers, and enable the “network effect” where it really matters; i.e., at the application level. Hence, it seems important that security research should enable and promote trust-enhancement infrastructures in human and computer networks; e.g., trust networks that exploit established social relations.

A general theory of trust in networks of humans and computers must be built on both a theory of behavioral trust and a theory of computational trust.1 This argument is motivated by increased participation of people in online social networking, crowdsourcing, human computation, and socio-economic protocols; e.g., protocols modeled by trust and gift-exchange games, norms-establishing contracts, and scams/deception. In this talk I illustrate a class of interactive trust protocols (ITP) that relies both on trustworthy properties of commodity systems2 (e.g., verifiable end-to-end trusted path) and new trust relations between protocol participants, since on-line verification of protocol compliance is often impractical; e.g., it can lead to undecidable problems, co-NP complete test procedures, and user inconvenience. New trust relations are established in ITPs using both selected social relations and social ties. I illustrate these concepts in specific instances of ITPs, namely protocols that help authenticate attributes of unknown parties,3 services, and software in a safe manner. 

[1]     Gligor, V. and Wing, J. 2011. Towards a Theory of Trust in Networks of Humans and Computers. In Proc. of the 19th International Workshop on Security Protocols. (Cambridge, UK, March 28-30, 2011). LNCS 7114, Springer Verlag, pp. 223 – 242.
[2]     Zhou, Z., Gligor, V., Newsome, J., and McCune, J. 2012. Building Verifiable Trusted Path on Commodity X86 Computers. In Proc. of IEEE Security and Privacy Symposium. (San Francisco, California, May 2012) pp. 616 – 630.
[3]      Kim, T. H-J., Gligor V., and Perrig, A. 2012. Street-Level Trust Semantics for Attribute Authentication. In Proc. of 20th Security Protocols Workshop, Cambridge University, April 2012.


Speaker Bio

Virgil Gligor

Virgil D. Gligor received his B.Sc., M.Sc., and Ph.D. degrees from the University of California at Berkeley. He taught at the University of Maryland between 1976 and 2007, and is currently a Professor of Electrical and Computer Engineering at Carnegie Mellon University and co-Director of CyLab. Over the past thirty-five years, his research interests ranged from access control mechanisms, penetration analysis, and denial-of-service protection to cryptographic protocols and applied cryptography. Gligor was an editorial board member of several IEEE and ACM journals, and the Editor in Chief of the IEEE Transactions on Dependable and Secure Computing. He received the 2006 National Information Systems Security Award jointly given by NIST and NSA in the US, and the 2011 Outstanding Innovation Award given by the ACM Special Interest Group on Security, Audit and Control.