The Media Access Control (MAC) data communication protocol sub-layer, also known as the Medium Access Control, is a part of the data link layer specified in the seven-layer OSI model (layer 2). It provides addressing and channel access control mechanisms that makes it possible for several terminals or network nodes to communicate within a multipoint network, typically a local area network (LAN) or metropolitan area network (MAN). A MAC protocol is not required in full-duplex point-to-point communication. In single channel point-to-point communications full-duplex can be emulated. This emulation can be considered a MAC layer. The Open Systems Interconnection Basic Reference Model (OSI Reference Model or OSI Model for short) is a layered, abstract description for communications and computer network protocol design, developed as part of Open Systems Interconnection (OSI) initiative. ... The application layer is the seventh level of the seven-layer OSI model. ... The presentation layer is the sixth level of the seven layer OSI model. ... The session layer is level five of the seven level OSI model. ... In computing and telecommunications, the transport layer is layer four of the seven layer OSI model. ... The network layer is level three of the seven level OSI model. ... The data link layer is layer two of the seven-layer OSI model as well as of the five-layer TCP/IP reference model. ... According to the IEEE 802 family of standards, Logical Link Control (LLC) is the upper sublayer of the OSI data link layer. ... This article does not cite any references or sources. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... The data link layer is layer two of the seven-layer OSI model as well as of the five-layer TCP/IP reference model. ... The Open Systems Interconnection Reference Model (OSI Model or OSI Reference Model for short) is a layered abstract description for communications and computer network protocol design, developed as part of the Open Systems Interconnect initiative. ... In communications, a channel access method is used to share a communications channel or physical communications medium between multiple users. ... In the context of telecommunications, a terminal is a device which is capable of communicating over a line. ... LOCAL AREA NETWORK Local area network scheme A local area network is a computer network covering a small geographic area, like a home, office, or group of buildings. ... Metropolitan area networks, or MANs, are large computer networks usually spanning a city. ... In telecommunications, duplex means two-way when referring to communications channels. ... Point-to-Point telecommunications is most recently (2003) referenced regarding wireless data communications for Internet or Voice over IP via radio frequencies in the multi-gigahertz range. ... This article or section does not cite its references or sources. ...

The MAC sub-layer acts as an interface between the Logical Link Control sublayer and the network's physical layer. According to the IEEE 802 family of standards, Logical Link Control (LLC) is the upper sublayer of the OSI data link layer. ... This article does not cite any references or sources. ...

The MAC layer provides an addressing mechanism called physical address or MAC address. This is a unique serial number assigned to each network adapter, making it possible to deliver data packets to a destination within a subnetwork, i.e. a physical network without routers, for example an Ethernet network. In computer networking a Media Access Control address (MAC address) or hardware address or adapter address is a quasi-unique identifier attached to most network adapters (NICs). ... A transitional network card with both BNC Thinnet (left) and Twisted pair (right) connectors. ... A graphic representation of relationships and source of the various variables representing a chunk of C subnets In computer networks, a subnetwork or subnet is a range of logical addresses within the address space that is assigned to an organization. ... A large core router used for major networks. ...

Media access control is often used as a synonym to multiple access protocol, since the MAC sublayer provides the protocol and control mechanisms that are required for a certain channel access method. This makes it possible for several stations connected to the same physical medium to share it. Examples of shared physical medium are bus networks, ring networks, hub networks, wireless networks and half-duplex point-to-point links. In telecommunication, the term multiple access has the following meanings: The connection of a user to two or more switching centers by separate access lines using a single message routing indicator or telephone number. ... In communications, a channel access method is used to share a communications channel or physical communications medium between multiple users. ... A transmission medium is a method or material substance which can propagate waves or energy. ... Image showing bus network layout A bus network Topology is a network architecture in which a set of clients are connected via a shared communications line, called a bus. ... Image showing ring network layout A ring network is a network topology in which each node connects to exactly two other nodes, forming a circular pathway for signals: a ring. ... 4 port ethernet hub An Ethernet hub or concentrator is a device for connecting multiple twisted pair or fiber optic Ethernet devices together, making them act as a single segment. ... Wireless networks are telephone or computer networks that use radio as their carrier or physical layer. ... In telecommunications, duplex means two-way when referring to communications channels. ...

Examples of packet mode multiple access protocols for wired multi-drop networks are: Wikipedia does not yet have an article with this exact name. ...

• CSMA/CD (used in Ethernet and IEEE 802.3),
• Token bus (IEEE 802.4)
• Token ring (IEEE 802.5)
• Token passing (used in FDDI).

Examples of multiple access protocols that may be used in packet radio wireless networks are: In computer networking, Carrier Sense Multiple Access With Collision Detection (CSMA/CD) is a network control protocol in which (a) a carrier sensing scheme is used and (b) a transmitting data station that detects another signal while transmitting a frame, stops transmitting that frame, transmits a jam signal, and then... Ethernet is a large, diverse family of frame-based computer networking technologies that operates at many speeds for local area networks (LANs). ... IEEE 802. ... Token bus is token ring over a virtual ring on a coaxial cable. ... IEEE 802. ... Token-Ring local area network (LAN) technology was developed and promoted by IBM in the early 1980s and standardised as IEEE 802. ... IBM token ring refers to IBMs implementation of token ring technology for linking personal computers in a local area network (LAN). ... Token Passing is a technique in which only that system can communicate that has token. ... In computer networking, fiber-distributed data interface (FDDI) is a standard for data transmission in a local area network that can extend in range up to 200 km (124 miles). ...

• CSMA/CA
• Slotted ALOHA
• Dynamic TDMA
• Reservation ALOHA (R-ALOHA).
• CDMA
• OFDMA

In computer networking, Carrier Sense Multiple Access With Collision Avoidance (CSMA/CA) is a network control protocol in which (a) a carrier sensing scheme is used, (b) a data station that intends to transmit sends a jam signal, (c) after waiting a sufficient time for all stations to receive the... ALOHAnet, also known as ALOHA, was a pioneering computer networking system developed at the University of Hawaii. ... Time division multiple access (TDMA) is a channel access method for shared medium (usually radio) networks. ... General Information Generically (as a multiplexing scheme), code division multiple access (CDMA) is any use of any form of spread spectrum by multiple transmitters to send to the same receiver on the same frequency channel at the same time without harmful interference. ... Orthogonal Frequency Division Multiple Access (OFDMA) is a multi-user version of the popular OFDM digital modulation scheme. ...

See also

• Channel access method
• MAC address
• Ethernet and CSMA/CD
• Token Ring and token passing
• CSMA/CA

In communications, a channel access method is used to share a communications channel or physical communications medium between multiple users. ... In computer networking a Media Access Control address (MAC address) or hardware address or adapter address is a quasi-unique identifier attached to most network adapters (NICs). ... Ethernet is a large, diverse family of frame-based computer networking technologies that operates at many speeds for local area networks (LANs). ... In computer networking, Carrier Sense Multiple Access With Collision Detection (CSMA/CD) is a network control protocol in which a carrier sensing scheme is used and a transmitting data station that detects another signal while transmitting a frame, stops transmitting that frame, transmits a jam signal, and then waits for... IBM token ring refers to IBMs implementation of token ring technology for linking personal computers in a local area network (LAN). ... Token Passing is a technique in which only that system can communicate that has token. ... In computer networking, CSMA/CA belongs to a class of protocols called multiple access methods. ...

References

This article was originally based on material from the Free On-line Dictionary of Computing, which is licensed under the GFDL.Media Access Control List The Free On-line Dictionary of Computing (FOLDOC) is an online, searchable encyclopedic dictionary of computing subjects. ... Bold text // “GFDL” redirects here. ...