$(1)$ For the DAC model discussed in Section $4\mathrm{.}3,$ an alternative representation of the $(1)$ For the DAC model discussed in Section $4\mathrm{.}3,$ an alternative representation of the

protection state is a directed graph. Each subject and each object in the protection state

is represented by a node $($a single node is used for an entity that is both subject and

object$).$ A directed line from a subject to an object indicates an access right, and the

label on the link defines the access right.

a$.$ Draw a directed graph that corresponds to the access matrix of Figure $4\mathrm{.}2$a$.$

b$.$ Draw a directed graph that corresponds to the access matrix of Figure $4\mathrm{.}3.$

c$.$ Is there a one$-$to$-$one correspondence between the directed graph representation

and the access matrix representation? Explain.

protection state is a directed graph. Each subject and each object in the protection state

is represented by a node $($a single node is used for an entity that is both subject and

object$).$ A directed line from a subject to an object indicates an access right, and the

label on the link defines the access right$\mathrm{.}136$

CHAPTER $4/$ ACCESS CONTROL

OBJECTS

Figure $4\mathrm{.}3$ Extended Access Control Matrix

Just Part B please:

b$.$ Draw a directed graph that corresponds to the access matrix of Figure $4\mathrm{.}3.$