DIMACS Theoretical Computer Science Seminar

Title: Exposure-Resilient Cryptography (survey)

Speaker: Yevgeniy Dodis, New York University

Date: November 10, 2003 3:30-4:30pm

Location: DIMACS Center, CoRE Bldg, Room 431, Rutgers University, Busch Campus, Piscataway, NJ


Much successful research has focused on developing cryptographic
protocols and algorithms which are secure (in some appropriate and
well-defined sense) under the assumption that ``secret'' information
is kept hidden from the adversary.  However, as cryptographic
algorithms are increasingly deployed on inexpensive, lightweight,
mobile, and/or unprotected devices, the risk of *key exposure* is
becoming a serious threat to the security of many real-world
systems. Indeed, in practice the attacks of this sort are, in many
cases, more likely than attacks which directly "crack" the
cryptographic assumptions on which the security of the scheme is
based. And while at first glance it might appear that not much can be
done to prevent or mitigate the damage caused by key exposure, the
study of *exposure-resilient cryptography* has led to a variety of
diverse and effective approaches for combating key exposure.

In this talk, I will survey several recent methodologies in the field
of exposure-resilient cryptography where I was involved. 
These methodologies include
(1) remotely-keyed cryptography
(2) two-party schemes (i.e., client-server model)
(3) key evolution (including forward-secure, key-insulated and
    intrusion-resilient cryptography)
(4) partial key exposure protection (incl. secret sharing)
(5) biometric authentication
(6) intentional key exposure protection (incl. traitor tracing).

The talk will be introductory and concentrate on items (1)-(3).