COLLOQUIUM
         Computer Science Department, Boston University

Speaker: Yevgeniy Dodis
         New York University

Date:  Wednesday, December 15, 2004
Time:  11am
Place: MCS 135 (for directions, see www.cs.bu.edu/colloquium)

Title: Exposure-Resilient Cryptography (Survey)

Abstract:

Much successful research has focused on developing cryptographic
protocols and algorithms which are secure 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
    * remotely-keyed cryptography
    * partial key exposure protection (incl. secret sharing)
    * two-party schemes (i.e., client-server model)
    * key evolution (including forward-secure, key-insulated and
      intrusion-resilient cryptography)
    * biometric authentication
    * intentional key exposure protection (incl. traitor tracing).

The talk will be introductory.