Glossary

M

MAC
Medium Access Control. A Protocol operating at the data link layer used to manage a station's access to the communication channel.

MAC Address
A unique address assigned to a station interface, identifying that station on the network. With Ethernet, this is the unique 48-bit station address. It is also known as the physical address.

MDI
Medium Dependent Interface. The name for the connector used to make a physical and electrical connection between a transceiver and a media segment. For example, the RJ-45-style connector is the MDI for 10BASE-T and 100BASE-TX.

MDI-X
An MDI port on a hub or media converter that implements an internal crossover function. This means that a "straight-through" patch cable can be used to connect a station to this port, since the required signal crossover is performed inside the port instead of in the cable.

MIB
Management Information Base. An MIB describes a set of managed objects. An SNMP management console application can manipulate the objects on a specific computer if the SNMP service has an extension agent DLL that supports the MIB. Each managed object in a MIB has a unique identifier. The identifier includes the object's type (such as counter, string, gauge or address), the object's access level (such as read, or read/write), size restrictions and range information.

Media Converter
A device that converts signals from one media type to that of another.

Multicast
A transmission initiated by one station and sent to many stations on the network.