One of the earliest mediums for storing computer commands and data. A magnetic drum is a cylindrical metal surface covered with a magnetic substance.
magnetic tape
A long, thin strip of celluloid-like material covered with a magnetic substance. Data blocks on a magnetic tape are accessed sequentially, so tape is normally used as secondary storage (for data backup and archival) versus primary storage.
management station
A centralized host or cluster of hosts at the heart of a management system.
Maximum Transmission Unit (MTU)
The maximum payload size supported by a given interface on a given segment of an OSI Layer 2 network. MTU does not include header or trailer bytes. MTU is used to indicate the maximum data payload to ULPs.
Mean Time Between Failures (MTBF)
A metric for the reliability of a repairable device expressed as the mean average time between failures of that device. MTBF is calculated across large numbers of devices within a class.
Mean Time To Failure (MTTF)
A metric for the reliability of non-repairable devices expressed as the mean average time between the first use of devices within a class and the first failure of devices within the same class. MTTF is calculated across large numbers of devices within a class.
mirror set
A set of partitions on physically separate disks to which data blocks are written. Each block is written to all partitions.
Mode-Conditioning Patch (MCP) cable
A special cable used by IBM mainframes to convert the transmit signal of a single mode optical interface to multi-mode.
multidrop interface
A bus interface supporting multiple device connections. Examples include the SCSI Parallel Interface (SPI), IEEE 802.3 10Base2, and IEEE 802.3 10Base5.
Multi-Source Agreement (MSA)
A voluntary agreement among multiple interested parties on the specifications of a transceiver. An MSA represents a consortium-based transceiver standard. MSAs allow switch, router, NIC, and HBA manufacturers to purchase transceivers from multiple sources without interoperability concerns. MSAs also allow transceiver manufacturers to sell to multiple consumers without engineering a unique interface for each switch, router, NIC, and HBA.
