Hierarchy-Based Access Control in Distributed Environments

Access control is a fundamental concern in any system that manages resources, e.g., operating systems, file systems, databases and communications systems. The problem we address is how to specify, enforce, and implement access control in distributed environments. This problem occurs in many applications such as management of distributed project resources, e-newspaper and payTV subscription services. Starting from an access relation between users and resources, we derive a user hierarchy, a resource hierarchy, and a unified hierarchy. The unified hierarchy is then used to specify the access relation in a way that is compact and that allows efficient queries. It is also used in cryptographic schemes that enforce the access relation. We introduce three specific cryptography based hierarchical schemes, which can effectively enforce and implement access control and are designed for distributed environments because they do not need the presence of a central authority (except perhaps for set- UP).

Information Access Patterns of Faculty in Arts and Sciences Colleges in Chidambaram

The term “user study” focuses on information use patterns, information needs, and information-seeking behaviour. Information- seeking behaviour and information access patterns are areas of active interest among librarians and information scientists. This article reports on a study of the information requirements, usefulness of library resources and services, and problems encountered by faculty members of two arts and science colleges, Government Arts & Science College and Sri Raghavendra Arts & Science College, Chidambaram.

African American Student Access To and Completion Of Higher Education, 1960-1992: A Correspondence Theory Analysis

“This presentation utilizes correspondence theory to analyze African American undergraduate student access to and completion of higher education in the United States. Findings from this research are presented and policy recommendations affecting Black student enrollment and graduation are discussed.”