International ISO/IEC Standard 9798-1: Information technology — Security techniques — Entity authentication — Part 1: General

Description

In systems involving real-time communication, entity authentication is a fundamentally important security service. Depending on the specific application and security goals, entity authentication can involve the use of a simple one-pass protocol providing unilateral authentication, or a multi-pass protocol providing unilateral or mutual authentication between the communicating parties. The goal of entity authentication is to establish whether the claimant of a certain identity is in fact who it claims to be. In order to achieve this goal, there should be a pre-existing infrastructure which links the entity to a cryptographic secret (for instance a Public Key Infrastructure). The establishment of such an infrastructure is beyond the scope of ISO/IEC 9798. A variety of entity authentication protocols are specified in ISO/IEC 9798 in order to cater for different security systems and security goals. For instance, when replay attacks are not practical or not an issue for a specific system, simple protocols with fewer passes between claimant and verifier may suffice. However, in more complex communication systems, man-in-the-middle attacks and replay attacks are a real threat. In such cases one of the more involved protocols of ISO/IEC 9798 will be necessary to achieve the security goals of the system. There are two main models for authentication protocols. In one model, the claimant and verifier communicate directly in order to establish the authenticity of the claimant identity. In the other model, entities establish authenticity of identities using a common trusted third party. The security properties of a scheme that must be considered before choosing an authentication protocol include the following: ⎯ replay attack prevention; ⎯ reflection attack prevention; ⎯ forced delay prevention; ⎯ mutual/unilateral authentication; ⎯ whether a pre-established secret can be used, or a trusted third party needs to be involved to help establish such a shared secret. Terms and definitions......Page 7 Symbols and abbreviated terms......Page 11 General requirements and constraints......Page 12