MAC (Media Access Control)

In the IEEE 802 protocols for shared multi access LANs, the data link lay is divided into two sublayers, The upper LLC (Logical Link Control) layer provides  a way to address a station on a LAN and exchange information with it. The lower MAC layer provides the interface between the LLC and the particular network medium that is in use (Ethernet, token ring, and so on).The MAC layer frames data for transmission over the network, and then passes the frame to the physical layer interface where it is transmitted as a stream of bits Framing packages information into distinct units that are transmitted one at a time on the network. If a frame is corrupted during transmission, only it needs to be resent—not the entire transmission.

MAN (Metropolitan Area Network) 

Metropolitan are a networks connect businesses to businesses, and businesses to WANs and the   Internet. A MAN is typically a backbone optical network that spans a metropolitan area, usually In a ring configuration. The telephone companies have provided MAN services in the form of SONET rings for years. The services are based on TDM(time division multiplexing),which is More suitable for voice than data.

MGCP (Media Gateway Control Protocol) 

MGCP is a protocol that operates between a media gateway and a media gateway controller, allowing the media gateway controller to control the media gateway. MGCP was developed as part of the convergence movement, which brings voice and data together on the  packet-switched Internet. MGCP is defined in RFC 2705 (Media Gateway Control Protocol Version 1.0, October 1999). A media gateway and a media gateway controller are components of  soft switch architecture.        

MIB (Management Information Base)

MIB (management information base) is a database consisting of managed objects accessed by network management protocols. An SNMP MIB is a set of specification from which an SNMP management station can query or set in the SNMP agent of a network device (e.g. router). SNMP has two standard MIBs. The first, MIB I, defines TCP/IP-based internets. MIB II, is an update to MIB II.Standard minimal MIBs have been defined, and many hardware providers have developed private MIBs in ASN.1 format allowing them to be compiled for use in a Nework Management System. In theory, any SNMP manager can talk to any SNMP agent with a properly defined MIB.

Microwave Communications

Microwaves are short-wave length, high-frequency signals that occupy the electromagnetic spectrum1, 000MHz (1GHz) to 1,000 GHz (1terahertz). This is just above the radio frequency range and just below the infrared range .The entire range is huge, but much of it is Not used for data communications, especially at the high- end due to water absorption.

MLPPP (Multilink PPP)

PPP Multilink is a bandwidth-on-demand protocol that can connect multiple links between two systems as needed to provide bandwidth on demand. The technique is often called bondingor link aggregation. For example, the two 64-Kbit/sec B channels of ISDN can be combined to form a single 128-Kbit/sec data channel. Another example would be to bind one or more dial-up asynchronous channels with a leased synchronous line to provide more bandwidth at peak  hours of the day.                                                                            

 MLPPP is defined in RFC 1990, “PPP Multilink Protocol” (August 1996). It is an extension  to the PPP (Point-to-Point Protocol). See “PPP (Point-to-Point Protocol)” for information about  the basic protocol. Microsoft Windows, Linux, and other operating systems support multilink. 

Many routers also support Multilink PPP and the ability to connect remote LANs with multiple  dial-up or ISDN lines.                                                                      

Multicasting 

 Multicasting is a way of efficiently transmitting text, audio, and video on

the Internet or an internal network to a select group of people, much like a conference call includes a select group of people. Instead of sending information in individual packets to each recipient, a single  message is sent to a multicast group, which includes all the people that want to participate in the multicast session. While multicasting is possible on a variety of networks.

Multiplexing and Multiplexers

Multiplexing is a technique of combining multiple channels of information over a single circuit or transmission path. Multiplexing may also take place in software, where multiple threads of information are delivered to a device or process at the same time. TCP/IP allows a single computer to multiplex two or more connections across a single network link at the same time. This occurs when you run two different programs to access the Internet, such as a Web browser and an e-mail program. Both programs use the same link to access different sites. Each application is assigned a specific port number in your computer by the TCP (or UDP) protocol.

Multilayer Switching

Multilayer switching is an evolution of LAN and internetworking technologies. Multilayer devices combine aspects of OSI layer 2 (the data link layer) and OSI layer 3 (the network layer) into hybrid switches that can route packets at wire speed. A basic switch is a multiport bridge These switches were developed to allow micro segmentation of LANs into large broadcast domains with small collision domains.

Multilink Point-to-Point Protocol     

See MLPPP (Multilink PPP).