Chapter 2. Access Control Matrix

GRANDPRÉ: Description cannot suit itself in words
To demonstrate the life of such a battle
In life so lifeless as it shows itself.

�The Life of Henry the Fifth, IV, ii, 53�55.

A protection system describes the conditions under which a system is secure. In this chapter, we present a classical formulation of a protection system. The access control matrix model arose both in operating systems research and in database research; it describes allowed accesses using a matrix.