Konstantin Beznosov
University of British Columbia
hosted by Cliff Neuman

Mon, February 6
2:00 pm PT
11th Floor Conference Room (1137)

The Secondary and Approximate Authorization Model and its Application to BellLaPadula Policies

The request-response paradigm used for access control solutions commonly leads to point-to-point (PTP) architectures, with security enforcement logic obtaining decisions from authorization servers through remote procedure calls. In massive-scale and complex enterprises, PTP authorization architectures result in fragile and inefficient solutions. They also fail to exploit virtually free CPU resources and network bandwidth. This talk introduces a three-fold approach to improving availability and performance of authorization solutions: employing publish-subscribe technologies, "actively" recycling authorizations, and flooding PEPs with speculatively precomputed "junk" authorizations.

After introducing the approach, the talk describes in detail the active authorization recycling part. Specifically, it defines the secondary and approximate authorization model (SAAM). In SAAM, approximate authorization responses are inferred from cached primary responses, and therefore provide an alternative source of access control decisions in the event that the authorization server is unavailable or slow. The ability to compute approximate authorizations improves the reliability and performance of access control sub-systems and ultimately the application systems themselves. The operation of a system that employs SAAM depends on the type of access control policy it implements. We propose and analyze algorithms for computing secondary authorizations in the case of policies based on the Bell-LaPadula model. In this context, we define a dominance graph, and describe its construction and usage for generating secondary responses to authorization requests. Preliminary results of evaluating SAAM-BLP algorithms demonstrate a 15% increase in the number of authorization requests that can be served without consulting access control policies.

Bio:

Konstantin Beznosov is an Assistant Professor at the Department of Electrical and Computer Engineering, the University of British Columbia, conducting research in the area of distributed systems security. Prior that, Dr. Beznosov was a Security Architect with Quadrasis, Hitachi Computer Products (America), Inc, where he designed and developed products for security integration of enterprise applications, as well as consulted large telecommunication and banking companies on the architecture of security solutions for distributed enterprise applications. Dr. Beznosov did his Ph.D. research on engineering access control for distributed enterprise applications at the Florida International University. He actively participated in standardization of security-related specifications (CORBA Security, RAD, SDMM) at the Object Management Group, and served as a co-chair of the OMG's Security SIG. He is a co-author of "Enterprise Security with EJB and CORBA" and "Mastering Web Services Security".