Motivation. Context: Our project “security for , and by social computing/networks” Here we discuss the “ by ” part, with emphasis on cryptographic utilities of social networks and case study on exploiting social networks for threshold crypto.
On the Cryptographic Utilities of Social Networkswith case study on exploiting social networks for threshold cryptography
Design considerations and preliminary results
Given social network G=(V, E). How should one shares her private key to her friends?
worst attack-resilience but best availability (each user gives a copy of its private key to all other users)
best attack-resilience but worst availability (corresponding to complete graph, namely each user shares it key to all the other users)
Shouhuai Xu and UTSA Team
University of Texas at San Antonio (http://www.cs.utsa.edu/~shxu)
S = T: no threshold crypto (benchmark)
S: # of compromised private keys
T: # compromised users
Heuristically optimal attack: choosing nodes from remainder graphs with decreasing degree
Security utility of anonymous social networks
Security utility of psychological soundness
Note: see slides for details; extended abstract appeared in ACM AsiaCCS’08; full version in submission.