Security Architecture & Access Control Flashcards

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

Answer: Well-formed transactions and separation of duties

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

Which property must a reference monitor satisfy?

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

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

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

Answer: The resource owner

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

The Trusted Computing Base (TCB) refers to:

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

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

A covert timing channel is best described as:

Answer: Signaling information by modulating the timing of system events

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

The Brewer-Nash (Chinese Wall) model is designed to prevent:

Answer: Conflicts of interest by restricting access based on prior access history

Brewer-Nash dynamically blocks access to data of competing clients once a user has accessed one company's data.

Common Criteria Evaluation Assurance Levels (EAL) indicate:

Answer: The depth and rigor of testing and assurance applied to a product

EAL1 through EAL7 reflect increasing rigor of design verification and testing, not product features.