Advanced Search

Browse by Discipline

Scientific Societies

E-print Alerts

Add E-prints

E-print Network

  Advanced Search  

A Logic of Authentication Michael Burrows Mart'in Abadi Roger Needham

Summary: A Logic of Authentication
Michael Burrows Mart'in Abadi Roger Needham
Questions of belief are essential in analyzing protocols for the authentication of prin­
cipals in distributed computing systems. In this paper we motivate, set out, and
exemplify a logic specifically designed for this analysis; we show how various protocols
differ subtly with respect to the required initial assumptions of the participants and
their final beliefs. Our formalism has enabled us to isolate and express these differences
with a precision that was not previously possible. It has drawn attention to features
of protocols of which we and their authors were previously unaware, and allowed us to
suggest improvements to the protocols. The reasoning about some protocols has been
mechanically verified.
This paper starts with an informal account of the problem, goes on to explain
the formalism to be used, and gives examples of its application to protocols from the
literature, both with shared­key cryptography and with public­key cryptography. Some
of the examples are chosen because of their practical importance, while others serve to
illustrate subtle points of the logic and to explain how we use it. We discuss extensions
of the logic motivated by actual practice---for example, in order to account for the use
of hash functions in signatures. The final sections contain a formal semantics of the
logic and some conclusions.


Source: Abadi, Martín - Department of Computer Science, University of California at Santa Cruz


Collections: Computer Technologies and Information Sciences