Multiple-Tiered Security Hierarchy for Web Applications Using Central Authentication and Authorization Service

The central authentication service (CAS) is a middleware for constructing a single sign on infrastructure for Web applications and has been developed by JA-SIG. In this paper, we investigate a multiple-tiered security hierarchy infrastructure for Web applications, by extending CAS to the central authentication and authorization service (CAS
²
). Since the new version of CAS (CAS3) supports the X.509 client certificate authentication, we use it as leverage to realize our multiple-tiered security hierarchy mechanism. As a result, CAS
²
uses X.509 client certification for not only authentication, but also authorization