ISA Security Architecture & Access Control 5

Question 1

The Clark-Wilson model enforces integrity primarily through which mechanisms?

Accepted Answer

Well-formed transactions and separation of duties

Answer

Clark-Wilson requires data to be changed only through authorized transformation procedures with duties separated.

Question 2

Which property must a reference monitor satisfy?

Accepted Answer

It must be tamperproof, always invoked, and small enough to be verified

Answer

A reference monitor mediates all access and must be tamper-resistant, non-bypassable, and verifiable.

Question 3

In discretionary access control (DAC), who decides who may access a resource?

Accepted Answer

The resource owner

Answer

DAC lets the owner of an object grant or revoke access to it at their discretion.

Question 4

The Trusted Computing Base (TCB) refers to:

Accepted Answer

The combination of hardware, firmware, and software responsible for enforcing security policy

Answer

The TCB includes all components critical to enforcing the system's security policy.

Question 5

A covert timing channel is best described as:

Accepted Answer

Signaling information by modulating the timing of system events

Answer

A timing channel conveys information by manipulating the timing of resource use, whereas a storage channel uses shared storage.

ISA - Information Security Analyst Certification Practice Test