eBay Inc.
Cryptography based fraud tracking

Abstract:

A cryptographic tracking engine is disclosed that can track a user's data over the Internet in a way that allows the user to maintain control over the data downstream while maintaining the security of the stored data. An online entity provides an identifier that is encrypted using a first mechanism. Further, the user provides a data item for an electronic communication between two users. The data item is encrypted using the first mechanism. The data encrypted using the first mechanism is stored in a cryptographic entry. Other data for the electronic communication between the a first and second user is encrypted using a second encryption mechanism, such as a block cipher. The user can then selectively expose data stored in the cryptographic entry on a block-by-block basis to track exchanges of data over the Internet.