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10 BaseT An Ethernet network implemented on twisted-pair cabling
Amplifiers Electronic component used to boost, or amplify, signals. Performance, also called gain, is measured in decibels. ATM (Asynchronous Transfer Mode) A specification from the ISDN standards for providing cell-relay services; a high-bandwidth networking standard. Audio Signal B-Channel (Bearer channel) A 64-Kbps ISDN user channel that carries digital data, PCM-encoded digital
voice, or a mixture of lower-speed data traffic (digital data or digitized
voice at a fraction of 64 Kbps).
Bandwidth The data-carrying capacity of a communications channel; measure (in Hertz) as the difference between the highest and lowest frequencies of the channel. Bandwidth varies depending on the transmission method. Baud Unit of signaling speed. The speed in baud is the number of line changes (in frequency, amplitude, etc.) or events per second . At low speeds, each event presents only one bit condition, and baud rate equals bps. But in common usage, baud rate and bps are often used interchangeably. BNC A bayonet-locking connector for miniature coax; BNC is said to be short for bayonet-Neill-Concelman.Contrast with TNC. BPS (Backup Power Supply) A device that switches to an alternate source when the main source fails. Compare UPS. BRI (Basic Rate Interface) An ISDN service referred to as 2B+D. BRI provides two 64-Kbps digital channels to your desktop. It's capable of simultaneously transmitting or receiving any digital signal-voice, video, or data. ISDN Terminal Adapters replace modems as the customer-premise connection to this service, enabling you to make direct connections of data terminals and telephones. Broadcast A method of transmitting messages to two or more stations at the same
time, such as over a bus-type local area network or by satellite; a protocol
mechanism that supports group and universal addressing . Any simultaneous
transmission to many receiving locations. One example is a message sent
over a multipoint line to all terminals that share the line.
Call Waiting Camera Chat CCITT (Comite Consultatif Internationale de Telegraphique et Telephonique) An international consultative committee that set world-wide communications standards (such as V.21, V22, and X.25). Replaced by the ITU-TSS. CISC (Complex Instruction Set Computing) A microprocessor architecture in which a large number of machine instructions are available. Compare RISC. Coax Codec A device that encodes and decodes signals. Compression A technique used to increase the number of bits per second sent over a data link by replacing often-repeated characters, strings, and command sequences with electronic code. When this compressed data reaches the remote end of the transmission link, the coded data is replaced with the actual data. Also calld "compaction". Control Plane
Data Plane Decoder Device Device Control Dialers Dialtone Directories
Equiptment Sharing
FM Noise Filters FPS Frames per Second Frames 1) Same as transmission block. 2) The sequence
of bits and bytes in a transmission block.. 3) The overhead bits an bytes
that surround the information bits in a transmission block.
Fractional T1 A service aimed at customers who don't need or
can't afford all 24 channels of a full T1 line. Fractional T1 service offers
the use of one or more channels The customers, then, pay only for the channels
they use.
File Transfer Protocol - a communication standard
used to pass files on TCP-IP networks.
Ground An electrical connection or common conductor that,
at some point, connects to the earth.
Head end Hub The core of a star-topology network or cabling
system.
Image Capture ISDN
(Integrated Services Digital Network)
IMUX Inverse Multiplexor IPX ISOW ISPs
Kbps Kilobits per second; standard measurement of data
rate and transmission capacity. One Kbps equals 1000 bits per second.
Lan Software LAN (Local Area Network) A Data-communications system confined to a limited geographic area (up to 6 miles or about 10 Kilometers) with moderate to high data rates (100 Kbps to 50 Mbps). The area served may consist of a single building, a cluster of buildings, or a camp of arrangement. The Network uses some type of switching technology and does not use common carrier circuits, although it may have gateways or bridges to other public or private Networks. Line Boosters Lumens Matrix
Microphones Monitors MPEG (Motion Picture Experts Group) A standard for lossy compression of full-motion video. Mute Multiplexor (MUX) A device used for division of a transmission facility
into two or more subchannels , either by splitting the frequency band into
a narrower bands or by allotting a common channel to several different
transmitting devices one at a time.
Netbeui A set of network-transport protocols developed by Microsoft. Noise Random electrical signal, generated by circuit components or by natural disturbances, that corrupt the data by introducing errors . NTI NTSC (National Television System Committee) A standard for color broadcasting developed in the 1950's for use mainly in North America and some of South America. NTU
Overlay Network Overlay Cards
Peer to Peer PAL (Phase Alternation by Line) A standard by color broadcasting used mostly in Europe. This system avoids the color distortion that appears in the NTSC system. POTS (Plain Old Telephone Service) The basic service provide by the public telephone network, without any added facilities such as conditioning. Promptus
Quad Box
Remote Device Control RCA adapter RGB Red, Green, Blue; a video standard in which the color signals for red, green and blue are carried on separate lines, then combined to form a color video picture. Horizontal and vertical sync are impose on one of the colors, usually green. RISC (Reduced Instruction Set Computing) Internal computing architecture in which processor instructions are pared down so that most can be performed in a single processor cycle, theoretically improving computing efficiency. RJ-11 Wiring with 4 or 6 wire modular connectors; commonly used for standard telephones lines. RJ-45 Wiring with 8-wire modular connectors; commonly used for serial data transmissions. Router A network device that examines the network addresses
within a given protocol, determines the most efficient pathway to the destination,
and routes the data accordingly. Operates at the Network Layer of the OSI
model.
Star Network Speed dialing The process of using short sequences of digits to represent complete telephone numbers. Self view Signal Speakers Splitter A device that multiplies one input into a number of identical ports. Socket Stack Stereo Student - Teacher Switch 1) Any device that makes or changes electrical
connections in a circuit. 2) Informal for data PABX.
The Cloud A public switch network which routing control is not in the software's hands. Transceiver A hardware device that links a node with a baseband network cable , functioning as both a transmitter and receiver. TCP-IP (Transmission Control Protocol/Internet Protocol) A layered set of protocols that allows sharing of applications among PCs, hosts, or workstations in a high-speed communications environment. Because TCP/IP's protocols are standardized across all its layers, including those that provide terminal emulation and file transfer, different vendors'computing devices ( all running TCP/IP) can exist on the same cable and communicate with one another across that cable. Corresponds to layers 4 (Transport) and 3 (Network) of the OSI reference model. T1 A digital carrier facility used to transmit a DS-1 formatted digital signal at 1.544 Mbps. A T1 carrier can transmit large volumes of information across great distances at high speeds at a (potentially) Lower cost than that provided by traditional analog service. A T1 carrier uses time-division multiplexing to manipulate and move digital information. It consists of one 4-wire circuit providing 24 separate 64-Kbps logical channels; the aggregate date rate equals 1.544 Mbps. Twisted Pair Two insulate copper conductors that are wound around each other, mainly
to cancel the effects of electrical noise; typical of standard telephone
wiring: Unshielded twisted pair contains no outside wraparound conductor.
UPS (Uninterruptible Power Supply) A device that continues to supply electricity for a period of time after
an outage. Compare BPS.
VCR Video Signal
White Board
Zydacron
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