0-9  A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z Fabry-Perot lasers A low cost, long wavelength laser used in short and intermediate reach transmitters. Because of a wide spectral width, these devices are not typically used in WDM systems. Lasers are available in either 1310nm or 1550nm wavelength windows. Most Gigabit Ethernet 1000Base-LX modules use 1310nm Fabry-Perot lasers. facilities-based service provider A communications service provider that owns a significant amount of its infrastructure elements-- fiber, wireless spectrum, networking systems, or co-location facilities -- as opposed to a service provider that leases most of these elements from other carriers or service providers. fast ethernet A standard for LAN communications, Ethernet defines the hardware and communications standard for communications at 10Mbps over coax, twisted-pair or fiber. Fast Ethernet refers to the 100Mbps version of Ethernet. Federal Communications Commission (FCC) The U.S. government agency charged with oversight of communications originating in the United States and crossing state lines. festooned networks Systems of short island-to-island, or coastline links that allow operators to use optical networks without repeaters for distances of up to 450 kilometers. Also called coastal stitching. fiber The structure that guides light in a fiber optic system. fiber Bragg gratings Fiber Bragg gratings offer a passive fiber-based means of filtering and stabilizing wavelengths to improve performance of optical components. They are used to preselect and filter signals in WDM to increase capacity and performance. Laser stabilization gratings improve the performance of lasers and allow looser manufacturing tolerances. Fiber gratings are made by exposing the core of a single-mode fiber to a periodic pattern of ultraviolet light. The light permanently increases the refractive index of the fiber's core. fiber exhaust When an optical fiber is used at capacity and cannot carry any more optical signals. fiber-optic Refers to the medium, optical fiber, and the technology associated with the transmission of information as light impulses along a glass or plastic wire or fiber. Transmission over fiber-optic wire requires repeating at intervals. Glass fiber requires more protection within an outer cable than copper. For these reasons, and because the installation of any new wiring is labor intensive, few communities yet have fiber-optic wires or cables in the local loop. fiber-optic cable A transmission medium that uses glass or plastic fibers, rather than copper wire, to transport data or voice signals via lightwaves as the transmission carrier. The signal is imposed on the fiber via pulses (modulation) of light from a laser or a light-emitting diode (LED). fiber optics A technology that uses light as a digital transmission carrier. fiber plant Aerial or buried fiber-optic cable that establishes connectivity between fiber-optic transmission equipment locations. fiber to the curb (FTTC) When fiber is laid from the central office to an optical network unit (ONU) located at the curbside of a home of business. fibre channel An industry-standard specification that originated in Great Britain which details computer channel communications over fiber optics at transmission speeds from 132 Mb/s to 1062.5 Mb/s at distances of up to 10 kilometers filter A passive optical component that passes certain frequencies of light and rejects all others. first-generation (1G) A generic name for first-generation analog cellular telephone standards such as AMPS and TACS for voice applications. fixed broadband wireless Technology that uses high-frequency microwaves (12-50 GHz) to transmit data packets over short distances at speeds of up to 150 Mbps. Service is usually deployed in metropolitan areas, as transmitting and receiving antennas must be placed on rooftops for direct line-of-sight communication. flash memory A storage medium that can retain memory without electricity and which is smaller in size than DRAM. Unlike DRAM, flash memory does not need a continuous electric charge to retain memory, but it can be electronically erased and reprogrammed. flip-chip integrated circuit (FCIC) An integrated circuit technology developed for high-reliability automated manufacturing. float Refers to the number of shares of a security that are outstanding and available for trading by the public. This number is calculated by subtracting insider shares, as determined in the company's proxy statements, from the outstanding shares. Smaller floats often lead to increased volatility, since a given number of shares being bought or sold will have a greater impact on the price. In the first year after an initial public offering, a company's float can vary greatly as lock up periods periodically expire, allowing insiders to freely trade their previously restricted shares. follow-on offering Refers to additional stock or bond issuances by companies that are already public. After an initial public offering, the company may require additional capital for further expansion. The offering will be dilutive to previous shareholders (i.e., earnings per share and book value per share fall), but is expected to more rapidly grow the company's revenue and earnings. forward error correction A communications technique that can correct bad data on the receiving end. Before transmission, the data is processed through an algorithm that adds extra bits for error correction. If the transmitted message is received in error, the correction bits are used to repair it. frame A fixed block of data transmitted as a single entity. In local area networks (LANs), the terms frame and packet are used synonymously. frame relay A packet-switched method of data communication (similar to, but more efficient than, the original X.25 WAN protocol provided by telecommunications carriers and Internet service providers. Frame relay can provide guaranteed bandwidth at no additional charge if the lines are open during periods of low traffic. Frame relay can run at speeds of 36 Kbps frame relay switch Network element that directs frame relay traffic across service provider networks. frequency converter A device that converts input current of one frequency to an output current of another frequency. frequency division duplexing (FDD) A transmission method that separates the transmitting and receiving channels with a guard band (some amount of spectrum that acts as a buffer or insulator). frequency division multiple access (FDMA) The technology used in the analog cellular telephone network that divides the spectrum into 30KHz channels. frequency division multiplexing (FDM) A technology that transmits multiple signals simultaneously over a single transmission path, such as a cable or wireless system. Each signal travels within its own unique frequency range (carrier), which is modulated by the data (text, voice, video, etc.). frequency source A device used to create a signal of a particular frequency or frequency range (e.g., and oscillator). fused fiber A bundle of fibers fused together so they maintain a fixed alignment with respect to each other in a rigid rod. fusion splicers In fiber optics, a splice created by localized heating of the ends of the two fibers to be joined.