Intel Research Seminar

DATE: Thursday, April 17, 2003
TIME: Noon - 1:30 pm
PLACE: Intel Seminar (417 S. Craig Street - 3rd Floor)

Mark D. Corner
University of Michigan

Transient Authentication for Mobile Devices

Laptops are vulnerable to theft, greatly increasing the likelihood of exposing sensitive information. Unfortunately, encryption alone does not address this problem. Current systems require users to imbue them with long-term authority for decryption, but that authority can be used by anyone who physically possesses the machine. Forcing the user to frequently reestablish his identity is intrusive and discourages use.

This tension between usability and security is eliminated through Transient Authentication, in which a small hardware token continuously authenticates the user's presence to the laptop over a short-range, wireless link. In this talk I present the four principles underlying Transient Authentication, and describe two concrete applications of the principles: protecting a file system and protecting application data. The ZIA encrypted file system requires decryption keys from the token; this dependency prevents access while the user is absent. Applications can be protected transparently by encrypting in-memory state when the user departs. This technique is effective but indiscriminate. Instead, applications can utilize an API for Transient Authentication, protecting only sensitive state.

Mark D. Corner is currently finishing his Ph.D. in Electrical Engineering Systems at the University of Michigan. He received the B.S. and M.S. degrees in Electrical Engineering from the University of Virginia. He has conducted research in cable modem MAC protocols, end-host adaptation in wireless networks, and mobile device security. His interests include mobile computing, operating systems, wireless networking, file systems, and security. Mr. Corner is a member of Eta Kappa Nu and Tau Beta Pi.

For Further Seminar Info:
Contact Kim Kaan, 412-605-1203, or visit

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