Conrad L. Young’s Wired Broadband and Related Industry Glossary of Terms with Acronyms As of 15 February 2012 Open Access This document is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial
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Zo = 138/√ε * log (D/d) where D = the inner diameter of the shield d = the outer diameter of the center conductor ε = the dielectric constant of the dielectric material  Figure. Coaxial Cable Diagram courtesy of Modern Cable Television Technology: Video, Voice, And Data Communications, 2nd Edition, Walter Ciciora, et al, ©2004 Elsevier Inc., page 428.
Chassis Mounting Connector Another name for pin-type connector. (Arris Glossary of Terms) CHILA CableCARD-Host Interface License Agreement Chirp In laser diodes, the shift of the laser’s center wavelength during single pulse durations. (FiberOpticsInfo). Chirp is the frequency (or phase) modulation, wanted or unwanted, resulting from a signal intensity modulation. A chirped signal will exhibit a modification of its spectrum as long as it travels along a fiber. Depending upon the sign of the chirp and of the dispersion of the fiber, a short pulse can be enlarged or compressed during propagation. To characterize the chirp of a signal, a chirp parameter α is defined as the ratio between phase modulation and intensity modulation. One method to measure the chirp parameter is the frequency discrimination technique, whereby the induced phase modulation is converted in phase modulation via a Gaussian tunable optical filter placed just after the modulator. The temporal signal is recorded on both sides of the optical filter. The temporal chirp parameter is related to the ratio of the difference and the sum of both measurements. (Hauden) 
Laser Chirp Graph courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/c Chroma 1. Attribute of a visual sensation that permits a judgment to be made of the amount of pure chromatic color present. 2. The portion of a composite video signal that carries the chrominance values, including hue and saturation. (Photonics dot com) Chroma Crawl An artifact of encoded video, also known as dot crawl or cross-luminance, occurs in the video picture around the edges of highly saturated colors as a continuous series of crawling dots and is a result of color information being confused as luminance information by the decoder circuits. (SVAT Electronics) Chroma Keying In television, nearly instantaneous switching between multiple video signals, based on the state, i.e., phase, of the color (chroma) signal of one, to form a single composite video signal. Note 1: Chroma keying is used to create an overlay effect in the final picture, e.g., to insert a false background, such as a weather map or scenic view, behind the principal subject being photographed. Note 2: The principal subject is photographed against a background having a single color or a relatively narrow range of colors, usually in the blue or green. When the phase of the chroma signal corresponds to the preprogrammed state or states associated with the background color, or range of colors, behind the principal subject, the signal from the alternate, i.e., false, background is inserted in the composite signal and presented at the output. When the phase of the chroma signal deviates from that associated with the background color(s) behind the principal subject, video associated with the principal subject is presented at the output. Synonyms color keying, [loosely] blue-screening, [in security] keying. (ATIS) Chromatic Dispersion Reduced fiber bandwidth caused by different wavelengths of light traveling at different speeds down the optical fiber. Chromatic dispersion occurs because the speed at which an optical pulse travels depends on its wavelength, a property inherent to all optical fiber. May be caused by material dispersion, waveguide dispersion, and profile dispersion. (FiberOpticsInfo) 
Dispersion Graph courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/c Chrominance Signal That portion of the NTSC color television signal that contains the color information. The chrominance signal is created by adding a 3.579545 MHz sine wave to a monochrome television signal. The signal is ignored by monochrome television receivers, but is picked up and decoded by a color set as part of the broadcast. The colors are shifted by degrees, and usually come in pairs to graph the full color spectrum. (Glossary of Terms dot Net) Chrominance-to-Luminance Crosstalk Also referred to as Chrominance-to-Luminance Intermodulation and Cross-Modulation (XMOD). An undesirable change in luminance amplitude caused by superimposition of some chrominance information on the luminance signal. Appears in a TV picture as unwarranted brightness variations caused by changes in color saturation levels. (SVAT Electronics) Chrominance-to-Luminance Differential Delay Measurement of the differential group delay between the chrominance (color) and luminance (black and white) frequency components of an analog television (TV) signal. When the differential group delay becomes sufficiently large the video color and luminance do not align on the display. A commonly used level of acceptable differential delay in cable systems is 200 ns. Differential delay is normally only a factor affecting the two (2) channels adjacent to the diplex filter guard band separating forward and return paths. (Rhea, Cable Television Signal Distribution) 
Figure. NTSC Analog TV Chrominance (Chroma) and Luminance Displayed for a Single TV Frame courtesy of Cable Television System Measurements Handbook, NTSC Systems, Hewlett-Packard, February 1994, page 1-2. CIE Commission International de l'Eclairage (International Commission on Illumination). An international standards-setting organization, based in Vienna, Austria, which is concerned with the development of (a) color-matching systems, (b) recommended practices and standards concerning the properties and applications of light, and (c) methods of measurement pertaining thereto. (ATIS) CIF Common Intermediate Format. A compromise television display format adopted by the CCITT which is relatively easy to derive from both PAL and NTSC. (Satnews) CIN Carrier to Intermodulation Noise; the ratio of the continuous wave (CW) carrier to the noise-like signals generated by the non-linearity of a broadband transmission system carrying a combination of analog signals and digitally modulated signals. These distortion products are analogous to the composite second order (CSO) and composite triple beat (CTB) products generated by analog carriers, but due to the pseudo random nature of the digital modulation signals, appear as a noise-like interference. When CIN products fall within the analog portion of the spectrum, their effect on the analog signal is similar to increasing thermal (random) noise. Since CIN is a distortion product, its contribution is dependent on the output signal level. Source: ANSI/SCTE 17 2007 “Test Procedure for Carrier to Noise (C/N, CCN, CIN, and CTN)”, dated 05 October 2007. Cipher An algorithm that transforms data between plaintext and ciphertext. Ciphersuite A set which must contain both an encryption algorithm and a message authentication algorithm (e.g., a MAC or an HMAC). In general, it may also contain a key-management algorithm, which does not apply in the context of PacketCable. Ciphertext The (encrypted) message output from a cryptographic algorithm that is in a format that is unintelligible. Circuit A system of conducting mediums designed to pass an electric current. (Arris Glossary of Terms) 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. (Arris Glossary of Terms) 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. (Satnews) 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. (FiberOpticsInfo) 
Circulator Diagram courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/c Cladding
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. (FiberOpticsInfo) Clamp A video processing circuit that removes the energy dispersal signal component from the video waveform. (Satnews) 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. (Arris Glossary of Terms) 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. (Arris Glossary of Terms) CLASS Custom Local Area Signaling Services Class A Refers to weight of coating for zinc-coated steel wires. (Arris Glossary of Terms) 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. (PCmagazine) 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. (PCmagazine) 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. (PCmagazine) Class C Refers to weight of coating for zinc-coated steel wires and is three (3) times the weight of Class A. (Arris Glossary of Terms) 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. (PCmagazine) 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. (PCmagazine) Class G Amplifier A variation of the Class AB design that improves efficiency by switching to different fixed voltages as the signal approaches them. (PCmagazine) 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. (PCmagazine) 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. (PCmagazine) 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. (FiberOpticsInfo) 
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. (Arris Glossary of Terms) 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. (Ruby Tech) 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. (ATIS) 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. (Arris Glossary of Terms) 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. (FiberOpticsInfo) 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). (CMAP Webinar) 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] (Wikipedia) References
CMCI Cable Modem to CPE Interface CMOS Complementary Metal Oxide Semiconductor; a family of ICs particularly useful for low-speed or low-power applications. (FiberOpticsInfo) 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 Download 2.22 Mb. Share with your friends:
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