M
maximum transmission unit (MTU).

Maximum packet size, in bytes, that a particular interface can handle.

Media Access Control (MAC) address.

Standardized data link layer address that is required for every port or device that connects to a LAN. Other devices in the network use these addresses to locate specific ports in the network and to create and update routing tables and data structures. MAC addresses are 6 bytes long and are controlled by the IEEE.

metropolitan area network (MAN).

Network that spans a defined metropolitan or regional area; smaller than a WAN but larger than a LAN.

multidwelling units (MDUs).

Buildings that contain multiple housing units, such as apartment complexes and university dormitories.

multiple service operator (MSO

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