Wired Broadband and Related Industry Glossary of Terms with Acronyms As of 13 June 2011 Compiled By: Conrad L. Young, Director, Broadband Technical Strategy



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A system of conducting mediums designed to pass an electric current.[Arr11]
Circuit Switched Data (CSD)
A type of telephone connection intended to carry data between two digital devices, such as ISDN digital data adapters and video conferencing systems. ISDN lines have to be provisioned correctly if they need to carry CSD connections.


Circuit Switched Data/Circuit Switched Voice (CSV/CSD)
An ISDN provisioning option that allows for both CSV and CSD telephone connections. Unless used to service an ISDN telephone, most home and business ISDN lines are configured to allow both.

Circuit Switched Network


This network transports information on communication links with a dedicated, end- to-end connection established at one or more switching centers between two connected parties for the length of their call. The public switched telephone network (PSTN) uses circuit switching.

Circuit Switched Voice (CSV)


A type of telephone connection intended to carry information between two analog- type devices, such as telephones, modems, and fax machines. ISDN lines have to be provisioned correctly if they need to carry CSV connections.

Circular Polarity



Electromagnetic waves whose electric field uniformly rotates along the signal path. Broadcasts used by Intelsat and other international satellites use circular, not horizontally or vertically polarized waves as are common in North American and European transmissions.[Arr11]
Circular Polarization

Unlike many domestic satellites which utilize vertical or horizontal polarization, the international Intelsat satellites transmit their signals in a rotating corkscrew-like pattern as they are down-linked to earth. On some satellites, both right-hand rotating and left-hand rotating signals can be transmitted simultaneously on the same frequency; thereby doubling the capacity of the satellite to carry communications channels. [Sat07]
Circulator

Passive three-port devices that couple light from Port 1 to 2 and Port 2 to 3 and have high isolation in other directions. [Fib111]

Circulator Diagram courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/c



C/Ku Band Feedhorn

Equipment located at the center of a satellite antenna used to collect C and Ku band signals and direct them into either a low noise amplifier (LNA) or low noise block converter (LNB).[Arr11]
Cladding

The low refractive index material which surrounds the core of the fiber and protects against surface contaminant scattering. In all-glass fibers, the cladding is glass. In plastic clad silica fibers, the plastic cladding may also serve as the coating.[Arr11]

Cladding Illustration courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/c

Cladding Mode

A mode confined to the cladding; a light ray that propagates in the cladding. [Fib111]

Clamp

A video processing circuit that removes the energy dispersal signal component from the video waveform. [Sat07]
Clamper

A device employed within cable operator headends and hubs to receive and process variable-rate digital content streams to output a constant bit-rate stream prior to switching.
Clamp Nut

A piece of a connector; the clamp nut mates with the entry body. This nut houses the ferrule, "O" ring carrier and "O" ring as one unit with no loose parts. Made of a high corrosion resistant aluminum alloy.[Arr11]
Clarke Belt

The circular orbital belt at 22,247 miles above the equator, named after the writer Arthur C. Clarke, in which satellites travel at the same speed as the earth’s rotation. Also called the geostationary orbit.[Arr11]


CLASS


Custom Local Area Signaling Services

Class A

Refers to weight of coating for zinc-coated steel wires.[Arr11]
Class A Amplifier

Analog amplifiers are cataloged by how much current flows during each wave cycle. Measured in degrees, 360º means current flows 100% of the time. The more current, the more inefficient and the more heat generated. The Class A amplifier conducts current throughout the entire cycle (360º). The Class A design is the most inefficient of the various Classes of amplifier and is used in low-power applications as well as in very high-end audio reproduction and ultra-linear cable industry amplifiers. Such devices may be as little as 15% efficient, with 85% of the energy wasted as heat.[PCm11]
Class B Amplifier

The current flows 180º for half the cycle, or two transistors can be used in a push-pull fashion, each one operating for 180º. More efficient than Class A, it is typically used in low-end products.[PCm11]

Class AB Amplifier



Combines Class A and B and current flows for 180º to 200º. Class AB designs are the most widely used for audio applications. Class AB amplifiers are typically about 50% efficient.[PCm11]
Class C

Refers to weight of coating for zinc-coated steel wires and is three (3) times the weight of Class A.[Arr11]
Class C Amplifier

Operating for less than half of one wave cycle (100º to 150º), Class C amplifiers are the most efficient, but not used for audio applications because of their excessive distortion.[PCm11]
Class D Amplifier

An audio amplifier that works in the digital domain. It generates the equivalent analog output for the speakers by using pulse width modulation (PWM) or pulse density modulation (PDM) rather than the traditional digital-to-analog conversion. See PWM and PDM. Because pulse modulation output signals are either on or off, Class D amplifiers produce far less heat than analog amplifiers. Reaching efficiencies greater than 90% compared to only 50% for analog, they are widely used for every amplification requirement from cell phone speakers to high-end stereos. Class D was not coined for "digital"; it was the next letter after Class C. However, it does produce a "digital-like" output because the signals are generated by turning a switch fully on or off. But it is not technically digital because the output is not digital data. It is a modulated audio signal that is feeding analog speakers and is equivalent to the output of a traditional analog amplifier. Some call this a "synthesized analog" output. See amplifier classes.[PCm11]
Class G Amplifier

A variation of the Class AB design that improves efficiency by switching to different fixed voltages as the signal approaches them.[PCm11]
Class H Amplifier

An enhancement of the Class G amplifier in which the power supply voltage is modulated and always slightly higher than the input signal.[PCm11]
Class T Amplifier

A variation of the Class D technique from Tripath. Class T modulates the pulses based on the individual characteristics of the output transistors.[PCm11]

Classifier


A set of criteria used for packet matching according to TCP, UDP, IP, LLC, and/or 802.1P/Q packet fields. A classifier maps each packet to a Service Flow. A Downstream Classifier is used by the CMTS to assign packets to downstream service flows. An Upstream Classifier is used by the CM to assign packets to upstream service flows.

Cleartext


The original (unencrypted) state of a message or data. Also called plaintext.

Cleave



The process of separating an optical fiber by a controlled fracture of the glass, for the purpose of obtaining a fiber end, which is flat, smooth, and perpendicular to the fiber axis. [Fib111]

Good Cleave Photo courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/c


Cleaving

The controlled breaking of a fiber so that the end surface is smooth.[Arr11]

CLEC


Competitive Local Exchange Carrier

CLI



Command Line Interface; a software tool, when employed with web-based management tools allows a network administrator to log on to an optical line terminal (OLT) converter to monitor, configure and control the activity of each Ethernet port within IEEE 802.3ah Gigabit Ethernet (GbE) PON compliant networks. [Rub11]
CLI

Cumulative Leakage Index; also referred to as Cumulative Signal Leakage Index, a mathematical calculation that represents a "snapshot" of a cable network's signal leakage performance at a given point in time. USA cable network CLI requirements are specified in US Code of Federal Regulations (CFR) 47: Telecommunication, Part 76: Multichannel Video and Cable Television Service.
Client
Commonly used term in PacketCable parlance to signify the customer premises equipment.

Cliff Effect

In the digital transmission of analog signals, including analog television and digital audio broadcasting (DAB), a signal-quality effect in which the decoded analog signal is either essentially flawless or totally unusable; i.e., it exhibits no gradual degradation or improvement attributable to the presence or absence of transient phenomena such as amplitude variations that may occur during transmission. Note: The cliff effect arises from the fact that analog variations in the intensity of the detected digital have no perceptible effect on the decoded analog signal; the only criterion for declaration of a digital mark is that the digital signal level is at or exceeds the decision level. The analog signal is then recovered without perceptible degradation. If the detection threshold is not met or exceeded, there will be no digital marks declared and the analog signal represented by them cannot be decoded, and will be lost entirely. [ATI11]
Clipping
The shearing off of the peaks of a signal. For a picture signal, this may affect either the positive (white) or negative (black) peaks. For a composite video signal, the sync signal may be affected.

Closed Circuit
A system of transmitting TV signals in which the receiving and originating equipment are directly linked by cable, microwave or telephone lines, without broadcasting through the air.

Closing Collar



A piece of a connector, this plastic part is moved for-ward in the entry body by tightening of the clamp nut, inclines on the closing collar and the terminal mate, and closes the fingers of the terminal onto the center conductor.[Arr11]
Cluster
The group of homes passed by a single fiber node.

Clustering


Grouping together of independent cable systems into a larger, more efficient single system that utilizes some of the same infrastructure.

cm



Centimeter; approximately 0.4 inches. [Fib111]
CM
Cable Modem

CMAP

Converged MultiService Access Platform. CMAP is a cable industry acronym describing an architecture combining the capabilities of an Edge QAM and a Cable Modem Termination System (CMTS) into a single platform. CMAP implements all DOCSIS® and MPEG transport stream (TS) QAMs from each cable operator headend (HE)/hub RF port. CMAP may be deployed in either integrated or modular format, similar to modular CMTS (M-CMTS). [CMA10]



CMMB

China Multimedia Mobile Broadcasting; a mobile television and multimedia standard developed and specified in People’s Republic of China (PRC) by the State Administration of Radio, Film, and Television (SARFT).[1] It is based on the Satellite and Terrestrial Interactive Multiservice Infrastructure (STiMi), developed by TiMiTech, a company formed by the Chinese Academy of Broadcasting Science.[2][3] Announced in October 2006,[1] it has been described as being similar to Europe's DVB-SH standard for digital video broadcast from both satellites and terrestrial 'gap fillers' to handheld devices.[3] It specifies usage of the 2.6 GHz frequency band and occupies 25 MHz bandwidth within which it provides 25 video and 30 radio channels with some additional data channels.[3] Multiple companies have chips that support CMMB standard - Innofidei who was the first with a solution March 28, 2007, Siano Mobile Silicon (with the SMS118x chip family, which support diversity and have superb performance) and more.[4] [5] [Wik1116]
References

    1. ^ a b Interfax China (2006-10-25). "China releases mobile TV industrial standard". Press release. http://www.interfax.cn/displayarticle.asp?aid=18260&slug=MOBILE%20TV. Retrieved 2007-04-14. 

    2. ^ "TiMi Technologies Co. Ltd.". Academy of Broadcasting Science. 2008-01-31. http://www.abs.ac.cn/en/Orgnization/Enterprises/200801/t20080131_2103.htm. Retrieved 2008-06-08. 

    3. ^ a b c Mike Clendenin (2006-12-18). "China's mobile-TV spec similar to Europe's". EETimes. http://www.eetimes.com/showArticle.jhtml;?articleID=196604027. Retrieved 2007-04-14. 

    4. ^ Interfax China (2007-03-28). "China releases first mobile TV chip based on CMMB standard - SARFT official". Press release. http://www.interfax.cn/displayarticle.asp?aid=22689&slug=CHINA-TELECOM-MOBILE. Retrieved 2007-04-14. 

    5. ^ Cai Yan (2007-03-29). "Chip supports China's CMMB mobile TV". EETimes. http://www.eetimes.com/news/semi/showArticle.jhtml?articleID=198700962. Retrieved 2007-04-14.


CMCI
Cable Modem to CPE Interface

CMOS

Complementary Metal Oxide Semiconductor; a family of ICs particularly useful for low-speed or low-power applications. [Fib111]

CMS
Call Management Server

CMSS
Call Management Server Signaling

CMTS
Cable Modem Termination System

CMTS-NSI
Cable Modem Termination System - Network Side Interface

C/N or CNR
Carrier-to-Noise Ratio

CO
Central Office


Coarse Wavelength Division Multiplexing (CWDM)
A method of combining multiple signals on laser beams at various wavelengths for transmission along fiber optic cables, such that the number of channels is fewer than in dense wavelength division multiplexing (DWDM) but more than in standard wavelength division multiplexing (WDM).

Coating



The material surrounding the cladding of a fiber. Generally a soft plastic material that protects the fiber from damage. [Fib111]

Fiber Optic Cable Cross-Section courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/c


Coaxial Cable
Copper or copper-sheathed aluminum wire surrounded by an insulating layer of polyethylene foam, used by cable television systems. The insulating layer is covered with tubular shielding composed of tiny strands of braided copper wire, or a seamless aluminum sheath, and protective outer skin. The wire and the shielding react with each other to set up an electromagnetic field between them. This system reduces frequency loss and gives cable its great signal-carrying capacity.


Coaxial Cable Cross-Section courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/c


Coaxiality (Axial Misalignment)
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