gloss_M

M

mail-enabled applications.

Mail-enabled applications are a class of software that incorporates e-mail's functionality, but provides additional services, such as workflow automation, intelligent mail handling, or contact management software.

main distribution facility.

In a structured wiring system, the main distribution facility is the portion of the wiring that's located in the computer room. From the main distribution facility extends the campus wiring subsystem, which runs to each building.

management information base (MIB).

A MIB is a repository of the characteristics and parameters that are managed in a device. Simple Network Management Protocol (SNMP) and Common Management Information Protocol (CMIP) use MIBs to identify the attributes of their managed systems.

Manufacturing Automation Protocol (MAP).

MAP is an ISO protocol for communicating among different pieces of manufacturing equipment.

Media Access Control (MAC).

The MAC is the lower sublayer of the Data-link layer (Logical Link Control is the upper sublayer), and it governs access to the transmission media.

mesh topology.

In a mesh network topology, any site can communicate directly with any other site.

Message Handling Service (MHS).

MHS is another name for ISO's X.400 protocols for store-and-forward messaging.

Message Handling System (MHS).

MHS is Novell's protocol for electronic mail and other message management, storage, and exchange.

Message Transfer Agent (MTA).

In ISO's X.400 electronic messaging protocols, the MTA is responsible for storing messages, then forwarding them to their destinations. The MTA is commonly implemented as the mail server.

Messaging API (MAPI).

Using Microsoft's MAPI, application developers can add messaging to any Windows application, and the program can gain access to the message storage, transport, and directory services of any MAPI server.

metropolitan area network (MAN).

A MAN covers a limited geographic region, such as a city. The IEEE specifies a MAN standard, 802.6, which uses the Dual Queue, Dual Bus access method and transmits data at high speeds over distances up to 80 kilometers.

MIB

In general, a Management Information Base is a schema, or structure, for a repository of characteristics and parameters managed in a network device such as a NIC, hub, switch, or router. Each managed device knows how to respond to standard queries issued by network management protocols. To be compatible with CMIP, SNMP, SNMP-2, RMON, or RMON-2, devices gather statistics and respond to queries in the manner specified by those specific standards. Many managed devices also have "private" MIB extensions. These extensions make it possible to report additional information to a particular vendor's proprietary management software or to other management software that's aware of the extensions. See CMIP, MIB-2, RMON, RMON-2, SNMP.

MIB-2

The expression MIB refers to the original SNMP MIB definition in IETF RFC 1157. The broader MIB-2 (RFC 1213) adds to the number of monitoring objects supported and is included in SNMP-2's MIB. However, SNMP-2's MIB (RFC 1907) is a superset of MIB-2.

mission-critical application.

A mission-critical application is one that is crucial to a company's continued operation. As corporations downsize from mainframes, many mission-critical applications are moved to networks.

MMX

According to Intel, the acronym "MMX" has no particular meaning, but it's generally inferred to mean "Multimedia Extensions." Specifically, MMX is implemented as a set of new microprocessor instructions for Intel's MMX-enhanced Pentium CPUs and its new Pentium II CPUs. MMX is not specific just to Intel, however, because Advanced Micro Devices, a competing chip manufacturer based in Sunnyvale, CA, has MMX-enabled its new K6 processor family. Many new Windows-based multimedia products for computer telephony or video conferencing are written to take advantage of the new MMX instructions.

multicast.

Multicast packets are single packets that are copied to a specific subset of network addresses. In contrast, broadcast packets are sent to all stations in a network.

multimedia.

Multimedia is the incorporation of graphics, text, and sound into a single application.

multimode fiber.

Multimode fiber- optic cable uses light-emitting diodes (LEDs) to generate the light to transmit signals. Multimode fiber is prevalent in data transmission.

multiplexing.

Multiplexing is putting multiple signals on a single channel.

Multipurpose Internet Mail Extensions (MIME).

MIME is an Internet specification for sending multiple part and multimedia messages. With a MIME-enabled e-mail application, users can send PostScript images, binary files, audio messages, and digital video over the Internet.

multistation access unit (MAU).

A MAU is a multiport wiring hub for Token Ring networks. IBM calls MAUs that can be managed remotely Controlled Access Units, or CAUs.