Question

In: Computer Science

3. For the following collection of statements, describe the sets of actions, objects, and subjects; and...

3. For the following collection of statements, describe the sets of actions, objects, and subjects; and draw an access control matrix to represent the scenario. 1 Mark

Alice can climb trees and eat apples.

Bob can climb fences, eat apples, and wave flags.

Trees can hurt apples.

Carol can jump waves and wave flags.

Expert Solution

Subject-

A subject is an active entity that carry out action/ operation on other entities or objects.

In the given question. Subjects are

1. Alice

2. Bob

3. Trees

4. Carol

Object-

An object is a passive entity (not a subject) or an entity acting passively (can be a subject too). in the given question Trees act as subject when they performs action hurt on apples and acts as an object when they get acted upon like climb trees. All the objects are

1. Trees

2. Apples

3. Fences

4. Flags

Actions are verbs performed by subjects on objects like climb, eat, wave

All the actions in the given question are:

1. Climb

2. eat

3. wave

4. hurt

5. Jump

Access control matrix is a table of subjects and objects indicating what actions individual subjects can take upon individual objects

		Objects
Subjects		Trees	Apples	Fences	Flags
Alice	Climb	eat
Bob		eat	climb	wave
Trees		hurt
Carol			jump	wave

venereology answered 1 year ago

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