B

Background check

The process of verifying a person’s professional, financial, and legal background, usually in connection with employment.

Baselines

Identifies a consistent basis for an organization’s security architecture, taking into account system-specific parameters, such as different operating systems.

Bell-LaPadula model

A formal confidentiality model that defines two basic properties:

• simple security property (ss property) A subject can’t read information from an object with a higher sensitivity label (no read up, or NRU).

• star property (* property) A subject can’t write information to an object with a lower sensitivity label (no write down, or NWD).

Best evidence

Original, unaltered evidence, which is preferred by the court over secondary evidence. See also Best evidence rule.

Best evidence rule

Defined in the Federal Rules of Evidence, states that “to prove the content of a writing, recording, or photograph, the original writing, recording, or photograph is (ordinarily) required.”

Biba model

A formal integrity model that defines two basic properties:

• simple integrity property A subject can’t read information from an object with a lower integrity level (no read down, or NRD).

• star integrity property (*-integrity property) A subject can’t write information to an object with a higher integrity level (no write up, or NWU).

Biometrics

Any of various means used, as part of an authentication mechanism, to verify the identity of a person. Types of biometrics used include fingerprint, palm print, signature, retinal scan, voice scan, and keystroke patterns.

Birthday attack

A type of attack that attempts to exploit the probability of two messages using the same hash function and producing the same message digest.

Black box testing

A security test wherein the tester has no prior knowledge of the system being tested.

Blackout

Total loss of electric power.

Block cipher

An encryption algorithm that divides plaintext into fixed-size blocks of characters or bits and uses the same key on each fixed-size block to produce corresponding ciphertext.

Bridge

A network device that forwards packets to other devices on a network.

Brownout

Prolonged drop in voltage from an electric power source such as a public utility.

Brute force attack

A type of attack in which the attacker attempts every possible combination of letters, numbers, and characters to crack a password, passphrase, or PIN.

Buffer (or stack) overflow attack

A type of attack in which the attacker enters an out-of-range parameter or intentionally exceeds the buffer capacity of a system or application to effect a Denial of Service or exploit a vulnerability.

Bus (computer architecture)

The logical interconnection between basic components in a computer system including CPU, memory, and peripherals.

Bus (network topology)

A network topology where all devices are connected to a single cable.

Business Impact Assessment (BIA)

A risk analysis that, as part of a business continuity plan, describes the impact to business operations that the loss of various IT systems would impose.