@conference {12238, title = {Identifying close friends on the internet}, booktitle = {Proc. of workshop on Hot Topics in Networks (HotNets-VIII)}, year = {2009}, month = {2009///}, abstract = {Online Social Networks (OSNs) encourage users to createan online presence that reflects their offline identity. OSNs create the illusion that these online accounts correspond to the correct offline person, but in reality the OSN lacks the re- sources to detect impersonation. We propose that OSN users identify each other based on interaction and experience. We believe that impersonation can be thwarted by users who possess exclusive shared knowledge, secret informa- tion shared only between a pair of OSN friends. We describe existing protocols that use shared secrets to exchange public keys without revealing those secrets to attackers. We present results from a user study on Facebook to show that users do share exclusive knowledge with their Facebook friends and attackers are rarely able to guess that knowledge. Finally, we show that friend identification can be extended using a web of trust built on the OSN friend graph. }, author = {Baden,R. and Spring, Neil and Bhattacharjee, Bobby} }