B

back door (backdoor)

An opening left in a program application (usually by the developer) that allows additional access to data. Typically these are created for debugging purposes and are not documented. Before the product ships, the back doors are closed; when they are not closed, security loopholes exist.

Back Orifice

An illicit server program that can be used to gain access to Windows NT/ 2000 servers and take control.

backup plan

A documented plan governing backup situations.

backup policy

A written policy detailing the frequency of backups and the location of storage media.

backups

Copies of data made to removable media.

Bell La-Padula model

The Bell La-Padula model was designed for the military to address the storage and protection of classified information. The model is specifically designed to prevent unauthorized access to classified information. The model prevents the user from accessing information that has a higher security rating than they are authorized to access. The model also prevents information from being written to a lower level of security.

best practices

A set of rules governing basic operations.

Biba model

The Biba model is similar in concept to the Bell La-Padula model, but it is more concerned with information integrity, an area that the Bell La-Padula model does not address. In this model, there is no write up, or read down. In short, if you are assigned access to Top Secret information, you cannot read secret information nor write to any level higher than the level to which you are authorized. This keeps higher-level information pure by preventing less reliable information from being intermixed with it.

BGP

See Border Gateway Protocol.

BIA

See Business Impact Analysis.

biometrics

The science of identifying a person by using one or more of their features. This can be a thumbprint, a retina scan, or any other biological trait.

biometric devices

Devices that can authenticate an individual based upon a physical characteristic.

birthday attack

A probability method of finding similar keys in MD5.

Blowfish

A type of symmetric block cipher created by Bruce Schneier.

boot sector

Also known as the Master Boot Record (MBR). This is the first sector of the hard disk, where the program that boots the operating system resides. It is a popular target for viruses.

Border Gateway Protocol

A protocol predominantly used by ISPs that allows routers to share information about routes with each other.

border routers

Routers that are used to translate from LAN framing to WAN framing.

brute force attack

A type of attack that relies purely on trial and error.

buffer overflow attack

A type of DoS attack that occurs when more data is put into a buffer than it can hold, thereby overflowing it, as the name implies.

business continuity planning

A contingency plan that will allow a business to keep running in the event of a disruption to vital resources.

Business Impact Analysis (BIA)

A study of the impact that could be possible if a disruption to a business's vital resources were to occur.