Classiication of Cryptographic Techniques in Authentication Protocols

In many published authentication protocols, the cryptographic services are coarsely speciied in that, whenever needed, a uniform notation is used to denote them while the exact nature of protection required is left unclear. In this paper we reason that such a coarse treatment not only forms a foundation why authentication protocols are error prone, but is also responsible for a typical feature of misusing redundancy which causes many protocols to be unnecessarily weak. We propose new notations to reene protocol speciications. The reenement leads to a methodology for the development of secure and strong authentication protocols.