In an RF overlay, carriers send traditional cable video to the home as its own separate wavelength within the fiber — a 1550 nanometer stream that rides alongside the 1490 nm wavelength, carrying everything else (the high-speed Internet, the voice and the video-on-demand, or VoD, content) as well as the 1310 nm wavelength going back the other way. [Con06]
Request for Proposal
A term sometimes applied to describe a fine herringbone pattern in a picture. May also cause a slight horizontal displacement of scanning lines resulting in a rough or ragged vertical edge of the picture. Caused by high-frequency interference.
A coaxial cable used for broadband video applications; RG6 has an 18 gauge center conductor, allowing a higher bandwidth than the RG59 cable, which has a smaller 20 gauge center conductor; RG6 uses standard “F” connectors for video equipment connections. [Lin07]
Red, Green, and Blue; the basic parallel component set in which a signal is used for each primary color, or the related equipment or interconnect formats or standards. [Fib111]
Revenue Generating Unit
RG is the military designation for coaxial cable and U stands for general utility. [Arr11]
Recording Industry Association of America
A cable whose conductors lie side by side in a single plane. Usually has a molded polyethylene insulation. [Arr11]
Using the secondary mouse button (usually the right button) to open context menus.
Relative Intensity Noise; often used to quantify the noise characteristics of a laser. [Fib111]
A network topology in which the nodes are connected in a closed loop. Data is transmitted from node to node around the loop, always in the same direction.
An oscillatory transient occurring in the output of a system as a result of a sudden change in input. Results in close-spaced multiple reflections, particularly noticeable when observing test patterns, equivalent square waves, sine-squared signal, or any fixed objects whose reproduction requires frequency components approximating the cutoff frequency of the system.
A network topology in which terminals are connected in a point-to-point serial fashion in an unbroken circular configuration. [Fib111]
Ring Network Diagram courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/r
Routing Information Protocol
The time taken to make a transition from one state to another, usually measured between the 10% and 90% completion points of the transition. Alternatively the rise time may be specified at the 20% and 80% amplitudes. Shorter or faster rise times require more bandwidth in a transmission channel. [Fib111]
Pulse Waveform Diagram courtesy of Fiber Optics Info, http://www.fiber-optics.info/fiber_optic_glossary/r
Rivest Cipher 4 (RC4)
A variable length stream cipher. Optionally used to encrypt the media traffic in PacketCable.
Random Jitter [Fib111]
An RJ-11 connector is the small, modular plug used for most analog telephones. It has six pin slots in the head, but usually only two or four of them are used.
RJ-11 Photo courtesy of Your Dictionary dot com, http://images.yourdictionary.com/rj-11
An RJ-45 connector is similar in appearance to a modular RJ-11 connector, but is wider and has eight-pin slot positions instead of six. RJ-45 connectors are used to connect ISDN S/T Interfaces and for 10-Base-T, 100Base-T, or 1000Base-T Ethernet cabling.
RJ-45 Photo courtesy of Your Dictionary dot com, http://images.yourdictionary.com/rj-11
Record Keeping Server
Remote Method Invocation
Rights Management System
Root Mean Square; technique used to measure AC voltages. [Fib111]
Rotary Mechanical Splice
The practice of stripping commercials in designated time periods across multiple cable channels. Can be an effective method for catching channel surfers.
Reconfigurable Optical Add/Drop Multiplexer; a passive device that can add, block, pass or redirect modulated infrared (IR) and visible light beams of various wavelengths in a fiber optic network. ROADMs are used in systems that employ wavelength division multiplexing.
Before the development of optical multiplexing devices such as ROADMs, signal routing in fiber optic networks was done by converting the IR or visible beams to electrical signals and routing those signals using conventional electronic switches. The rerouted electrical signals were then converted back into IR or visible beams. In a conventional ROADM, switching is accomplished without optical-to-electrical or electrical-to-optical conversion using three operations called add, drop and cut-through. An outgoing IR or visible beam can be generated (the add operation) or an incoming beam terminated (the drop operation). A beam can also be passed through the device without modification (the cut-through operation). In combination, these functions allow optical signal routing of considerable complexity. The configuration of the system can be changed remotely. Two major ROADM technologies are in current use. They are called wavelength blocking (WB) and planar light-wave circuit (PLC). Wavelength blocking, also called first-generation ROADM technology is the older of the two. When a wavelength change is necessary for a particular channel, the IR or visible light beam at the original wavelength is filtered out and its data extracted. Then the data is impressed onto a beam of another wavelength. PLC or second-generation ROADM technology in effect combines these steps, streamlining the process and reducing the cost. Neither the WB nor the PLC ROADM designs facilitate true optical branching, in which beams of any wavelength can be directly routed to any desired port without the need to perform multiple intermediate operations. Optical branching capability is important in the deployment of efficient, reliable, high-volume optical networks designed to provide advanced services such as video on demand (VoD). An evolving technology called enhanced ROADM (eROADM) makes true optical branching possible. [Sea11]
ROADM Diagram courtesy of International Engineering Consortium, http://www.iec.org/newsletter/jan06_2/broadband_1.html