Abstract:

In modern network settings, secure protocols are run concurrently with other
arbitrary protocols. The interaction of different protocols with each other
can be exploited by malicious parties to successfully attack the protocols,
even if each protocol is secure when considered in isolation. To make things
worse, adversarial parties may design and release "malicious" protocols
whose sole purpose is to interact with secure protocols and compromise their
security. In fact, it has been shown that in modern network settings like
the Internet, it is easy to launch such attacks on real protocols. In this
talk, we discuss recent progress on a research project whose focus is the
development of a theory for analyzing the security of protocols under these
and other attack scenarios. We present definitions of security for different
types of protocol composition, where many (possibly different) protocols are
run concurrently in a network. We then present a number of positive and
negative results regarding the feasibility of achieving security under these
definitions.  Finally, we will discuss research goals for the future.