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Evaluating Trust in a Public Key Certification Authority

Chadwick, David W., Basden, Andrew (2001) Evaluating Trust in a Public Key Certification Authority. Computers and Security, 20 (7). pp. 592-611. ISSN 0167-4080. (doi:10.1016/S0167-4048(01)00710-6) (The full text of this publication is not currently available from this repository. You may be able to access a copy if URLs are provided) (KAR id:13520)

The full text of this publication is not currently available from this repository. You may be able to access a copy if URLs are provided.
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With the growth of many different public key infrastructures on the Internet, relying parties have the difficult task of deciding whether the sender of digitally signed message is really who the public key certificate says they are. We have built an expert system that calculates the amount of trust, or trust quotient, that one can place in the name to public key binding in a certificate. The structure of the expert system is based on the CPS framework of Chokhani and Ford (RFC 2527), whilst the relative importance of the various factors that comprise the trust quotient, were determined by interviewing PKI experts from around the globe. This paper discusses the knowledge analysis strategy employed to collect this expert information and how we used it to develop the KBS. The analysis of the results of the interviews are also presented, and they can be summarised succinctly as "there are some factors concerning trust in a PKI which nearly all experts agree upon, and there are other factors in which there is very little agreement at all". The importance of identifying contextual factors when building a knowledge base is very important. In many cases, a disagreement between experts, as shown by a bimodal split in importance, was traced to differences in context and we show how this can be a source of new knowledge.

Item Type: Article
DOI/Identification number: 10.1016/S0167-4048(01)00710-6
Uncontrolled keywords: trust; trust quotient; public key infrastructure; certification authority; expert system; certification practice statement; certificate policy; X.509
Subjects: Q Science > QA Mathematics (inc Computing science) > QA 76 Software, computer programming,
Divisions: Divisions > Division of Computing, Engineering and Mathematical Sciences > School of Computing
Depositing User: Mark Wheadon
Date Deposited: 24 Nov 2008 17:58 UTC
Last Modified: 16 Nov 2021 09:51 UTC
Resource URI: (The current URI for this page, for reference purposes)

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