An Algebra for Assessing Trust in Certification Chains

Author(s): Audun Josang

Download: Paper (PDF)

Date: 4 Feb 1999

Document Type: Reports

Additional Documents: Slides

Associated Event: NDSS Symposium 1999

Abstract:

Open networks allow users to communicate without any prior arrangements such as contractual agreement or organisation membership. However, the very nature of open networks makes authenticity difficult to verify. We show that authentication can not be based on public key certicates alone, but also needs to include the binding between the key used for certication and it’s owner, as well as the trust relationships between users. We develop a simple algebra around these elements and describe how it can be used to compute measures of authenticity.