Data Protection and Security

V

Access Control

V.I

Introduction

In the context of computer security, access control is the ability to limit and control the access to computer resources. We name resources as objects and in a proper terminology we say active subjects access passive objects with some specific access operations. As depicted in Figure 1, accesses are mediated by an abstract machine that is called reference monitor.

The access control mechanism implemented typically authenticates subjects (principles) using some mechanism such as password or Kerberos, then mediate their access. We leave the discussion of authentication to another chapter.

Figure V.I-I:

The fundamental model of access control. [click to enlarge]

V.I.I Q