M

M of N Control method

A rule which states that in order to access the key server if n number of administrators have the ability to perform a process, m number of those administrators must authenticate for access to occur. This may involve physical presence.

MAC (Media Access Control)

See Media Access Control.

MAC (Mandatory Access Control)

A security policy wherein "labels" are used to identify the sensitivity of objects. When a user attempts to access the object, the label is checked to see if access should be allowed (i.e., determining if the user is operating at the same sensitivity level). It is called "mandatory" because labels are automatically applied to all data (and can only be changed by administrative action), as opposed to "discretionary" where it is up to the user to decide whether or not to apply a label.

MAC address

The address that is either assigned to a network card or burned into the NIC. This is how PCs keep track of one another and keep each other separate.

macro virus

A software exploitation virus that works by using the macro feature that many applications include.

malicious code

Any code that is meant to do harm.

mantrap

A device, such as a small room, that limits access to a small number of individuals. Mantraps typically use electronic locks and other methods to control access.

Man in the middle attack

An attack that occurs when someone/thing that is trusted intercepts packets and retransmits them to another party. This has also been called TCP/IP hijacking in the past.

mathematical attacks

Attacks focused on the encryption algorithm itself, the key mechanism, or any potential area of weakness in the algorithm.

Mean Time Between Failure (MTBF)

The measure of the anticipated incidence of failure of a system or component.

Mean Time To Repair (MTTR)

The measurement of how long it takes to repair a system or component once a failure occurs.

Message Authentication Code (MAC)

A common method of verifying integrity. The MAC is derived from the message and a key.

message digest

The signature area within a message.

Message Digest Algorithm (MDA)

An algorithm that creates a hash value. The hash value is also used to help maintain integrity. There are several versions of MD. The most common are MD5, MD4, and MD2.

isuse-Detection IDS (MD-IDS)

A method of evaluating attacks based on attack signatures and audit trails.

media

Any storage medium.

Media Access Control (MAC)

A sublayer of the Data Link layer of OSI that controls the way multiple devices use the same media channel. It controls which devices can transmit and when they can transmit.

modems

A communication device that converts digital computer signals into analog tones for transmission over the PSTN and converts them back to digital upon reception. The word "modem" is an acronym for "modulator/demodulator."

modification attacks

An attack that modifies information on your system.

multi-factor

The term employed anytime more than one factor must be considered.

multicasting

Sending data to more than one address.

multipartite virus

A virus that attacks a system in more than one way.