We present three attacks on the authentication protocol that has been proposed for the so-called global mobility network in the October 1997 issue of the IEEE Journal on Selected Areas in Communications. We show that the attacks are feasible and propose corrections that make the protocol more robust and resistant against two of the presented attacks. The aim is to highlight some basic design principles for cryptographic protocols, the adherence to which would have prevented these attacks.

Presents the introductory welcome message from the conference proceedings.

The authors describe a simple logic. The logic uses the notion of channels that are generalisations of communication links with various security properties. The abstract nature of channels enables one to treat the protocol at a higher abstraction level than do most of the known logics for authentication, and thus, one can address the higher level functional properties of the system, without having to be concerned with the problems of the actual implementation. The major advantage of the proposed logic is its suitability for the design of authentication protocols. They give a set of synthetic rules that can be used by protocol designers to construct a protocol in a systematic way.

The increased interest in protocols that provide a total order on message delivery has led to several different definitions of total order. In this paper we investigate these different definitions and propose a hierarchy that helps to better understand the implications of the different possibilities in terms of guarantees and communication cost. We identify two definitions: weak total order and strong total order, which are at the extremes of the proposed hierarchy, and incorporate them into a consistent design. Finally, we propose high-level algorithms based on a virtually synchronous communication environment that implement the given definitions.