Anonymous credit cards and their collusion analysis
Steven H. Low, Nicholas F. Maxemchuk, Sanjoy Kumar Paul · IEEE/ACM Transactions on Networking · 1996
Communications networks are traditionally used to bring information together. They can also be used to keep information apart in order to protect personal privacy. A cryptographic protocol specifies a process by which some information is transferred among some users and hidden from others. We show how to implement anonymous credit cards using simple cryptographic protocols. We pose, and solve, a collusion problem which determines whether it is possible for a subset of users to discover information that is designed to be hidden from them during or after execution of the anonymous credit card protocol.