Fiber Optics Illustrated Dictionary - Part 56 pdf

Fiber Optics Illustrated Dictionary Joint Utility Pole Examples A terminal (end) utility pole. Wires are aerially strung to only one side of the pole and aguy supports the other side. The lines on end poles may be termi- nated or may feed into a vertical conduitfor connection to nearby underground wiringfacilities. Joint Utility Poles These two photographs illustrate somewhat different utility poles located several blocks apart. The one on the left is a terminating pole, connecting conducting wires on only one side of the pole with conduits for channeling lines to the ground. The pole on the right is a more common mid-block pole that primarily supports the lines and passes them along to the next pole (and to local utility subscribers) without ending the connections or directing them earthward. Both poles include a variety of wires, cables, insulators, and transform- ing devices. In spite of their geographic and functional differences, these two poles clearly have many common structural characteristics, arising from various joint utility pole regulations and agreements. Most of the structural aspects have been worked out over the decades based upon electrical characteristics and safety and maintenance needs. Recently, the role ofjoint utility poles has be- come more complex. Not only has the demand for phone services increased, but additional types of 542 Amid-blockutilitypole in which wires are supported and passed on to the next pole in the path and to the nearby buildings of local utility subscribers. Not all poles have transformers, but three are shown here, in cylindrical metal housings. media, including copper-based high-speed data lines and fiber optic cables, have been added to the joint pole hierarchy, often severely stretching the space and weight limitations ofjoint poles, especially in densely populated urban areas. The problems of interference have increased as well. High-speed copper data lines, for example, have special needs that are different from voice lines. The loading coils added as induction structures to reduce attenuation (loss of signal) on voice lines may help facilitate voice transmissions over longer distances but they can also increase interference in high-speed data lines. Utility Pole General Characteristics Most utility poles are made of wood, usually ce- dar or fir, although some regions have poles made of metal or cement. Wood and metal poles are generally between 20 and 30 feet in height. Depend- ing upon the type of pole and the terrain, the setting depth is usually about 4 or 5 feet into the ground. The accessible ground surface around the curb is termed the grade. © 2003 by CRC Press LLC Joint Utility Pole Regions (Spaces) and Common Components higher voltage (primary) power conductor insulator (usually ceramic) crossarm - structural support for multiple power lines secondary power conductor (to supply nearby residences and businesses) stepdown transformer - steps down the voltage from the higher voltage conductors to secondary conductors leading to residences and businesses cable TV (CATV) bundle - there may be two CATV cables, one for the cable trunk line and one for the feeder (attached lower on the pole with connecting drops between the two) CATV loops, line extenders telephone wire bundle various amplifiers, power inverters, and line extenders may be located on conducting wires within arm's reach of the utility pole vertical wire casing/conduit utility closet (typically holds power supply/backup battery for CATV) grounding rods and wires • There are often various cylindrical or box- shaped metal cabinets attached to a pole. These have a variety of functions. They may contain battery or other auxiliary power supplies (usually located higher up on the poles), may include tools or components, or may be cabinets associated with CATV installations (usually located lower on the pole than the CATV cable). Mounting brackets must be designed and attached so they are strong enough to withstand the effects of wind, or the minor collision ofa vehicle with the pole. In general, in urban areas, the pole should be about 5 feet behind the face of a curb and about 6 feet from the shoulder of the road, with differences related to local speed limits and odd intersection situations that may require other solutions. In general, utility poles are not permitted to be placed in traffic islands. Highways generally require greater offsets than city streets. Hierarchical Organization of Components While there are variations, in general, higher voltage conductors are located higher up on the pole, for safety and to minimize their effects on data-carrying lines. In most cases, conducting wires are required to be at least 12 feet from the accessible ground (grade). In some cases, where alleys or driveways are involved, the requirement may be as high as 18 feet. A static grounded wire may be at the top of the pole, to draw lightning away from the conducting wires below. The power lines carrying high voltage between power supply substations are located near the tops of the poles and there may be one or more. Sec- ondary power lines for carrying lower voltages to local subscribers are lower than the primary power supply conductors but higher than the communications media. Stepdown transformers between the primary and secondary power lines provide voltage conversion functions. A multigrounded neutral (MGN), generally located below the primary power supply, is an unin- sulated conductor for carrying unbalanced residual current. Various grounding wires and rods run down the side of the pole, as needed. There may also be terminating equipment on end poles, or conduits for connecting an end pole with underground wiring. A grounding rod at the base of the pole may be used to ground the MGN. 543 © 2003 by CRC Press LLC Fiber Optics Illustrated Dictionary stock market that is particularly relevant in light of direct trading activities as they occur over the Inter- net (as opposed to traditional trading that was more often filtered through brokers). As in the Prisoner's Dilemma, people may well be better off not trading at all (not confessing), but given the social and eco- nomic dynamics, it's hard to resist. Joshi has proposed that with so many involved, the market becomes more fragmented and volatile with the result that it may be- come more difficult to achieve any gains. JOTP Java Open Trading Protocol toolkit under development for client/server implementations of the Internet Open Trading Protocol (IOTP). JOTP clients are implemented as protocol commerce beans for the Java Wallet. JOTP servers are based upon the Enter- prise JavaBean and Servlet component models. Inter- operability is through XML-based Open Trading Pro- tocol transaction transport mechanisms. joule (symb. - 1) An absolute meter-kilogram-second (MKS) unit ofwork or energy equal to 10 7 ergs. An SI unit of energy equal to 1 kg m 2 S·2. Named after James Joule. See work. Joule, James (1818-1889) An English physicist who studied the dynamics and efficiency of various types of engines. Joule demonstrated that when mechani- cal work is used in generating heat, the ratio of work to heat is a constant quantity. Ajoule, the absolute unit ofwork or energy, is named after him. Joy, William (Bill) One of the codevelopers of Sun Microsystems' Java, attributed with the original idea for the programming language which eventually be- came Java. In the early 1990s, Joy met with the members of the Stealth Project to develop a language which could create short, powerful programs. See Gosling, James; Java. joystick A hardware input device that receives and transmits signals containing directional information to acomputing device. Commonly used for manipu- lation of computer software on screen pointers and selectors. In its most common form, a joystick re- sembles an aircraft steering control, and mayor may not include buttons. It is commonly used for video gaming applications. See mouse, potentiometer, trackball. JPEG (pron. jay-peg) See JBIG Alliance, Joint Pho- tographic Experts Group. JPEG file format The JPEG image compression format was designed to be used with a wide variety of continuous tone images, without restrictions as to colors, resolution, content, etc. Depending on the software used to generate the file, the format provides the user with trade-offoptions between compression levels and the quality (lossiness) of the image, and is symmetric, with compression and decompression re- quiring about the same amount of time and process- ing power. Common file extension conventions to identify JPEG files are .jpeg and .jpg. JPEG is not perfect for every type of image. Continu- ous tone images with many colors generally look good when rendered and compressed with JPEG, in spite of the substantial loss of information and reduction in file size. Crisply rendered images with few colors, 544 sharp boundaries, and thin lines tend to take on a fuzzy or speckled appearance when compressed into JPEG format, and should probably be processed with adifferent compression format more suitable for that type of image. The traditional JPEG format does not support trans- parency. Iftransparency is required, another fonnat such as Portable Network Graphics (PNG) or Compu- serve Graphics Interchange Format (GIF) may be used. JPEG is not usually the best fonnat for the storage and rendering of images to be printed on a traditional press, as it is a "lossy" format; that is, it does not re- tain all the information from the original. The reso- lutions ofprinted images on paper are much higher than those of renderings on acomputer screen (1800 dpi vs. 75 dpi). An image that looks good on the computer may look fuzzy and inadequate on paper. The TIFF format is generally a better choice for images to be printed, as the format retains a great deal of information about the image, while still providing rea- sonably good compression ratios with common compression schemes. JPEG is actually a family ofcompression formats and many implementations of it are quite minimal. For example, JFIF is a bare bones version of JPEG commonly found on the Web, and SPIFF has been for- mally defined to be upwardly compatible with JFIF. Variations on the JPEG format can often be identi- fied by looking at the first few bytes in the file header. Work is ongoing on the newer JPEG2000 standard. See JBIG, MPEG, TIFF. jukebox 1. Ahardware appliance or peripheral that holds and can selectively or randomly access multiple data storage items, generally of the same type, such as audio CDs, tapes or records; computer dis- kettes; tapes; or cartridges. For audio applications, 20 to 100 items may be accessible, and access may be very quick, whereas for archival purposes, especially with high-capacity storage tapes, there may be 5 to 20 tapes, and access may be slow. 2. Asoftware tool for selecting and playing digitized audio or multimedia files in the manner of a traditional phonograph jukebox from the 1950s. In fact, many softw~e jukeboxes have user interface designs that mimic old-time jukeboxes. The jukebox analogy is now being extended to multimedia resources on the Web. Users can store their original audio or multimedia files on a Web site and users can access the jukebox through a Web- page interface as a shared resource. JRG GIl Joint Rapporteur Group global information infrastructure. A group of rapporteurs and experts from various ITU study groups brought together to further discuss and coordinate global standards-setting tasks. JST See Japan Solderless Terminal. JStamp Acommercial battery-operated one-inch by two-inch circuit containing a realtime, native Java technology module developed by Systronix. The matchbox-sized module includes a 32-bit CPU, flash RAM and SRAM, and can handle realtime hardware interrupts. It's based on the aJile Systems Inc. chip design. The low-power-consumption module can © 2003 by CRC Press LLC operate up to 40 hours, depending upon the implementation. It is suitable for devices such as Personal Digital Assistants running Java applications, including graphics animations. This level ofminiaturiza- tion is likely to spawn a whole host ofcarry-around applications that haven't existed in the desktop world due to lack of portability and high relative cost. JTAG Joint Test Action Group. An international body, founded in 1985, JTAG seeks to develop electronics-related test methodologies and related standards. These standards are then recommended to various appropriate standards bodies, such as the IEEE. JTAPI See Java Telephony API. JTC See Joint Technical Committee. JTIE See JitterTrack of Time Interval Error. Judge Harold Greene See Greene, Harold. Jughead Named in association with other Internet tools, including Veronica, Jughead provides a way for Gopher administrators to access and retrieve menu information from the various gopher servers on the Net. They stretched alittle to put an acronym to this one, but ended up with "Jonzy's Universal Gopher Hierarchy Excavation and Display." See Archie, Veronica, gopher, Gopher. Julian calendar A solar-based calendar in wide- spread use (some traditions use a lunar calendar) in the western world that arose historically from calendar reform instituted by Julius Caesar, after his con- quest of Egypt. The Julian calendar is based on a 365- day year divided into 12 somewhat equal months with leap years used to reconcile the difference between the calendar divisions and actual celestial events (like adjusting a clock that runs slightly fast or slow in relation to clocks based on accepted time references). After some initial experimentation with leap years, they were standardized to occur every 4 years. The actual solar year is slightly shorter than the Julian solar year, which is 365.25 days with the 4-year leap year convention. In the short run, this discrepancy doesn't bother most people but for theologists, farm- ers, and scientists (especially astronomers), the discrepancy can be important, especially since it adds up: after a century, the calendar is almost a day out of synch with the actual solar year. By the time the Italian Renaissance came about, when intellectual cu- riosity was high and systematic observations were being strongly established, the calendar was re- formed, with input from a number of astronomers and theologians. In 1582, Pope Gregory XIII issued a papal bull establishing the Gregorian calendar, setting October 5, 1582, in the old calendar to October 15, 1582, in the new calendar, to synchronize the ad- ministrative calendar with the solar calendar. The day for using the leap year adjustment was changed as well, from February 25 to February 29. In essence, however, it is the same basic type ofcalendar as the Julian calendar. The Gregorian calendar coexisted with the Julian calendar for centuries, being first adopted by the Catholic communities. Gradually, however, nations switched over to the Gregorian calendar, though many of them not until the 1900s. Historians often have difficulty pinpointing historical dates related to the advancement of science in Eu- rope because of the coexistence of the two calendar systems. In many cases, even when a historical record is dated, it might not be definitely known in which system it was recorded. jumbo Large, oversized, bulky, etc. in relation to others of its type. Jumbo cables are typically those that are fatter overall or which carry larger numbers of optical filaments. Jumbo chips or LEDs are those that are largest in their category. Jumbo lenses are those that have a wider diameter or thickness than typical lenses. jumbogroup In general, an aggregation of associated devices, transmission media, lines, or channels. In analog voice phone systems, a group within the hierarchy for multiplexing that has been established as a series ofstandardized increments. The CCITT established ajumbo group as consisting of 6 mastergroups, each of which in tum comprises 10 supergroups or 600 voice channels. The lTU-T, successor to the CCITT, defines a mastergroup as comprising 5 supergroups, whereas in the U.S., com- mercial carriers follow a standard of a mastergroup comprising 10 supergroups. (Confused yet? The Voice Circuits Hierarchy diagram should help.) More recently, ajumbogroup has been described as the highest FDM multiplexing level that contains 3600 voice channels as contained within 6 master groups. The important thing is to remember the jumbogroup's place in the telephone setVice hierarchy. That way, ifcapacities change and jumbogroup ag- gregations change, the relationship to other groups is still understood. Ajumbo group is occasionally called a hypergroup. jump hunting In telephony, a means of searching for an available trunk or extension in nonconsecutive order by dialing the first number of the trunk to indicate which trunk to search. Also called nonconsecutive hunting. jumper 1. A temporary or customized connection used to bypass or reroute a circuit, frequently in the fonn ofa wire, often ashort one; common on printed circuit boards. Jumpers are used to test circuits, cor- rect errors, or make last minute changes in circuit board manufacture. They may also be used to set operating attributes on configurable peripherals such as hard drives (e.g., SCSI settings). Sometimes wire jumpers are equipped with alligator clip heads to facilitate quick connection. 2. A small, paired electrical protruberance on aprinted circuit board, intended for configuring a circuit with settings that are infre- quent. This type of jumper is common on hard drives, where there may be a row of seven or eight jumpers. The connections are "jumped" with very small U- shaped electrical tabs with plastic casings to set SCSI ill numbers or other configuration parameters. If the circuit is jumped, the tab is placed over both prongs in the circuit to complete the electrical connection. If not, the tab is removed or placed to one side on a single prong, so as to leave the circuit unconnected. junction box, J boxA wire or fiber optic encasement box for coupling cables. It is often made of metal or 545 © 2003 by CRC Press LLC Fiber Optics Illustrated Dictionary other moisture- or fire-retardant materials, and is commonly found in homes and businesses. Junction boxes are frequently hidden in closets or attached to the sides of buildings near a utility/network drop. They are crucial to most wire and fiber transmission technologies. Every time a transmission link is interrupted, split, joined, amplified, or otherwise affected at a wiring junction, there is the possibility of damage, short circuits, noise, or loss of signal. The main functions of the junction box are to protect the wiring from moisture, heat, or other conditions that may damage the wires or fiber filaments or short an electrical circuit, to provide a means to connect sections of transmission lines so they can be combined to create a longer total line, to protect humans and animals from acciden- tal electrical shock from contact with electrical wires, switchers, or amplifying components, and to provide a means to readily access, connect, or change the wiring or effect repairs at a par- ticular point in a circuit. The junction box is commonly placed at the junction or demarcation point between internal and external wiring. It may also be placed at a point in a line where other lines are split off from a main line or where sections of line are connected, or where the signal on a line needs to be amplified. In building wiring, the J box often also incorporates fuses or breaker switches to protect against overload and fire hazards. The sim- plest J boxes are those that house the wiring for a switch or other wire connection point in a wall or ceiling. In fiber optics applications, the terminal and connecting boxes for the optical fiber splicing and connection points are also called J boxes. Since fiber optic media are more difficult to handle and connect than most electrical wires, J boxes for fiber optics must be built to accommodate the differences between electrical current and laser light transmissions. They may have specialized termination components and usually lock the fibers in place more rigidly and precisely than wires in an electrical J box to accommodate fiber transmission and physical properties such as orientation and preferential bend radius. Blown fiber techniques were developed in part to reduce the number ofjunction boxes in a fiber optic transmission line. In oceanic transmission cables, special techniques for installing and maintaining cables are necessary and the junction boxes must be built to withstand the rig- ors of salt water and cold temperatures. They must also be designed so that connections may be changed in an underwater environment without creating short circuits. Grounding and termination are accomplished differently from land-based installations. Many of the present undersea junction installation and maintenance boats are descended from vessels that laid the first transatlantic cable in the 1800s and the mine-laying naval ships of World War I. Since ma- rine junction boxes can't be hidden within walls, they must be designed so that they don't catch in fishing nets or interfere with nearby boating and diving activities. In radio and computer electronics, J boxes are often constructed by hobbyists to add electronic switches or components to existing systems. The box supports and protects wiring connections and may include Voice Circuits Hierarchy - Multiplexed Groupings Comprising a Jumbogroup D A c In analogphonesystems, lines are aggregated into standardized groups of the generalformat shown here. In this example, a single line (A) is combined with 11 other individual lines into a group (B), then 5 groups are multiplexed toform a supergroup (C), 10 supergroupsform a mastergroup (D), and 6 mastergroupsform ajumbogroup (E). 546 © 2003 by CRC Press LLC switches, buttons, status lights and connection termi- nals for data and power. J boxes are distinguished from interface devices mainly in that they do not provide complex data conversion or modulation functions, but focus on simple wiring circuits as an extension to the main circuit. As in many aspects of electronics, the distinction is not always clear; there is overlap between interface devices and the more advanced J boxes (sometimes called smart J boxes). Advanced electronic J boxes have been designed for industrial installations to au- tomatically evaluate the characteristics of an electrical line and log the information or report possible problems to an operator. These are essentially aJ box and associated electronic devices housed in one unit, using the J box nomenclature for familiarity in mar- keting the products. junctor A connective circuit extending between frames ofa switching unit, terminating in a switching device on each frame, as in an internal network trunk. JUNET Japan Unix Network. A noncommercial Japanese network dedicated to promoting communi- cation among researchers in and outside Japan. Junior Wireless Club Limited Apioneer amateur radio organization, formed in 1909. In April 191 0, one of the young members, W.E.D. Stokes, Jr., made history when he represented the club before a U.S. Sen- ate Commerce Subcommittee. As president of the club, he opposed a proposed bill to license wireless operators. Stokes also argued for a specified wave- length for amateur use to be allocated to amateur radio communications. In October 1911, the group changed its name to the Radio Club of America. See Radio Club of America. JuniperNetworksA software/hardware firm backed by prominent telecommunications firms 3Com, Lu- cent Technologies, and Northern Telecom. It has developed routing software in competition with Cisco Systems products and a number of channelized, long- haul, and multi link hardware interface products. See Junos routing code. JUNOS routingcodeA router operating system (OS) announced by Juniper Networks, Inc. in 1998 that en- ables high-speed network fOlWarding across complex paths. It is competitive with the Cisco Internetwork Operating System (lOS) dominant on Internet-de- ployed routers. In 2001, an upgrade was released to support the use of multiprotocol label switching (MPLS) on virtual private networks (VPNs) over In- ternet Protocol (IP) networks. just a bunch of disks JBOD. A disk data management system in which various organizational aspects of hard disk storage may span more than one disk. For example, some operating systems allow a user to transparently create large partitions (or file structures) that span more than one drive (as opposed to breaking up a drive into smaller segments) or even to create a file structure across more than one parti- tion, thus making flexible use of the total virtual storage space available on a system. As an example, imagine you have three 1 GByte drives and want to save a big animation file (e.g., a movie) that takes up 2.5 GBytes of drive space. Most consumer desktop systems aren't configured to do this; they will indicate that there isn't enough space, even if total disk space is 3 GBytes. In a JBOD system, the file management algorithms can manage the virtual space specified and split the file and file pointers appropriately over the various disk segment boundaries. The name is likely derived from RAID (redundant array of inexpensive disks) and has some aspects in common, in that the system is used with multiple disks, but it's not the same (in fact, it could be implemented across a RAID system). RAID is intended to provide redundancy on a system through mirroring or striping of data, whereas mOD is intended to provide more flexible management of data across several disks. See redundant array of inexpensive disks. Just-Enough-Time JET. A network transmission protocol proposed by Qiao and Yoo in 1999 for use with optical burst switching (OBS). It embodies the use ofa delayed connection reservation (DR) and the capability of integrating delayed reservation with fiber optic delay line-based buffered burst multiplex- ers (BBMs). JET is considered by its developers to be more efficient for use with OBS than TAG-based OBS protocols. In a given transmission path with a known number of hops, JET and OBS protocols can support multi- path routing. Deflection routing can also be supported with the control packet selecting an alternate. out- bound link and setting the switch for the following data burst. JET does not mandate buffer use or buffer size relative to the number of bursts or bits that can be stored or delayed simultaneously. Each burst will be buffered at the source during an offset interval and need not be buffered at intermediate nodes, if no blocking is encountered by the control packet. If a control packet is blocked, DR and BBM can be used to increase the effectiveness through buffer allocation and management. See optical burst switching. Just-In-Time nT. A term taken from the inventory and distribution field to describe computer process- ing systems that handle data translation or other tasks at runtime. For example, Just-in- Time compilers compile code on-the- fly instead of running a code interpeter (e.g., SmallTalk) in situations where this approach may be faster. See Java Virtual Machine. JvNCnet John von Neumann Center network. A mid- level, northeastern U.S. regional network owned and operated by Global Enterprise Services, Inc. JvNCnet was the first T-I research network and supported the networking needs of the U.S. National Science Foun- dation (NSF). In 1989, the National Science Foundation announced a 3-year award to JvNC to establish Phase II, with input from academic and industrial institutions and representatives from the National Science F ounda- tion and others. Phase II connected a number of prominent networks and organizations to JvNCnet, including Bell Laboratories, Rutgers University, Princeton University, Siemens Research, and JANET. 547 © 2003 by CRC Press LLC Fiber Optics Illustrated Dictionary GES provides users with the hardware and telephone line necessary to connect to JvNCnet access points with a variety of transmission speed options. 548 JWICS See Joint Worldwide Intelligence Commu- nications System. JXML See Java XML. © 2003 by CRC Press LLC k abbrev. kilo See kilo K 1. symb. cathode (in pinout diagrams). 2. abbrev. Kelvin. 3. symb. 1 024 (commonly used with quanti- ties of data elements such as bits). Thus, 2 10 or 2K = 2048 bits. Also a prefix as in Kbps (kilobits/sec). 3. symb. 1000 when used to indicate monetary quanti- ties. For example, $50K typically indicates a salary of $50,OOO/year. K plan, K-plan See keysheet. K Series Recommendations A series of ITU-T guidelines for preventing interference in telecommunications systems (there are also interference-related topics in various other Series Recommendation documents). These guidelines can be purchased from the ITV-T. Since ITV-T specifications and recommendations are widely followed by vendors in the telecommunications industry, those wanting to maxi- mize interoperability with other systems need to be aware of the information. A full list of general cat- egories is listed in Appendix C and specific series topics are listed under individual entries in this dictionary, e.g., J Series Recommendations. See K Se- ries Recommendations chart. K-bandA designated portion of the electromagnetic spectrum ranging from 10.9 to 36 GHz. The K-band range is commonly used for small antenna satellite transmissions. See band allocations, Ka-band, Ku-band. K-carrier A four-wire broadband cable carrier system utilizing frequencies to about 60 kHz. K-style handset The designation for the shape of newer telephone handsets which resemble older desk phone G style handsets, except that they have a more squared-off design on the ear- and mouthpieces. They are heavier and more substantial than some of the newer cordless or cell phone handsets, which tend to be flat and small. See G style handset. K56flex modem A 56k data telecommunications modem technology developed by Rockwell Semicon- ductor Systems and Lucent Technologies to enable higher data throughput rates over standard analog telephone lines (POTS). The modem was competitive with u.S. Robotics' x2 technologies in the ab- sence of an established 56k standard. Higher data rates were achievable by looking at the structure of the phone lines and the prevalent patterns of modem usage. These modems were designed to do less conversion as analog phone lines were actually part of a predominantly digital system. In addi- tion, the K56flex modems were optimized for down- stream transmissions, with upstream being delivered at speeds up to 33.6 Kbps. K56flex modems are backwardly compatible with the lTV Y:34 standard to enable fallback when the server doesn't support K56flex. When the Y:90 standard was approved by the International Telecommunication Union (lTV), Rockwell and Lucent announced that new modems would also be compatible with the lTV V.90 standard (formerly called \ZFast). Some K56f1ex modems could be upgraded to support V.90. See V.Fast, V Series Recommendations. kA abbrev. kiloampere, 1000 amperes. Ka-band The designated portion of the electromagnetic spectrum in the high microwave/millimeter range, approximately 18 to 22 GHz. The Ka-band is used primarily by small antenna satellite transmissions, and is intended to support future applications, for example, mobile voice. A 500-MHz allocation within this spectrum is earmarked for nongeostation- ary fixed satellite orbit services, and there are spec- trums for local multipoint distribution services (LMDS), mobile satellite services, and geostationary satellite services. See band allocations for chart. KA9Q Gopher server A Web-accessible Gopher server developed by Chris McNeil, with enhance- ments by McNeil and Peter Crawshaw. The Web version supports email, FTP, Gopher, NTP, Finger, and SLIP servers plus security through IP filtering. The name is based upon the underpinnings of Phil Kam's KA9QNET/NOS. KA9Q NOS TePIIP Phil Kam's popular commer- cial TCP/IP software implementation for packet radio communications. The name of the software comes from his amateur radio callsign. It is available in Bor- land C++ and a 32-bit protected-mode version for DJGPP. It is popular for its compatibility with lower memory and CPU systems (not everyone wants to throwaway perfectly good older computing systems). Amateur radio enthusiasts publish a number of amateur radio TCP/IP server gateways on the Web, which connect initially through telnet. Some ofthese are password-protected, and some can be accessed by 549 © 2003 by CRC Press LLC Fiber Optics Illustrated Dictionary anonymous login, somewhat similar to anonymous login sessions on FTP sites. Kahle, Brewster Project leader for the Wide Area Information Server (WAIS) at Thinking Machines Corporation in Massachusetts (1989), and involved with the company since its founding in 1983. WAIS, Inc. was sold to AOL in 1995. Kahle designed the CPU of the Connection Machine Model 2 in the 1980s. He founded the Internet Archive and co- founded the Alexa Web information company in April 1996, and is active in promoting scholarly re- positories of Internet history and documents that might otheIWise have a short shelf life. See Wide Area Information Server. Kahn, Robert "Bob" E. (1938- ) A prominent American developer ofnetwork technologies, Kahn coauthored A Protocol for Packet Network Internet- working (1974) describing Transmission Control Pro- tocol (TCP). In 1977, he co-demonstrated a gateway system that could interconnect packet radio wi th the ARPANET. In 1986, he founded the not-for-profit Corporation for National Research Initiatives to support and develop the National Information Infrastruc- ture (NIl). Kahn has received many awards for his contributions to the development of the Internet, including the Na- tional Medal of Technology, in 1997. See Cerf, Vinton G.; packet radio. Kalman, Rudolf Emil (1930- ) AHungarian-born American mathematician and engineer who studied at MIT and Columbia University in the 1950s. Since then he has held a number of professor and research positions at institutions such as ffiM and Stanford and served as director of the Center for Mathematical System Theory at the University ofFlorida and chair of Mathematical System Theory in ZUrich. Kalman is considered a significant pioneer in the field of control theory and is particularly remembered for codeveloping linear filtering techniques with R. Bucy, in the early 1960s. He studied and modeled state- space concepts such as linear-quadratic control, minimality, and observability and applied them to systems analysis. In the 1970s, he was among those who introduced the use of algebra and geometry in linear and nonlinear control theory. Kalman has received many engineering awards, including the IEEE Medal of Honor (1974). He was elected to the National Academy of Sciences in 1994. Kalman fIlter Amathematical means of removing unwanted noise from a stream of data, developed by R. Kalman and R. Bucy. In 1960, when the development of computer algorithms was still largely in its infancy, Kalman proposed a recursive means of solv- ing discrete-data linear filtering problems through a least-squares method. In "A New Approach to Lin- ear Filtering and Prediction Problems," Kalman de- scribes his objective as obtaining the specification of a linear dynamic system which accomplishes the prediction, separation, or detection of a random signal and points out some of the limitations oftraditional solutions prior to the Kalman approach. There is a discrete Kalman filter and an extended 550 © 2003 by CRC Press LLC K Series Recommendations, cont. Recom. Description K.20 Resistibility of telecommunication equipment .• installed in a telecommunications center to overvoltages and overcurrents K.21 Resistibility of telecommunication equipment installed in customer's premises to overvoltages and overcurrents K.22 Overvoltage resistibility of equipment connected to an ISDN TIS bus K.23 " Types of induced noise and description of noise voltage parameters for ISDN basic user networks K.24 Method for measUririgradio- frequency induced noise on telecommunications pairs K.25 Protection of optical fibre cables K.26 Protection of telecommunication lines against harmful effects from electric power and electrified railway lines K.27 Bonding configurations and earthing inside atelecommunication building K.28 Characteristics of semi-conductor arrester assemblies for the protection of telecommunications installations 1< 29 Coordinated proteetionschemes for telecommunication cables below ground K.30 Positive temperature coefficient(PTc) thennistors K.31 Bonding configurations and earthing of telecommunication installations inside a subscriber's building K.32 Immunityrequirements and test methodsforelectrostaticdischaCgeto telecommunicatioIl equipment- generic EMC recommendation K.33 Limitsforpeople stlfetyrelated~o coupiingintotelecommunicatio ll system from AC electric power and AC electrified railway installations in fault conditions K.34 Classification of electromagnetic environmental· conditions for telecommunication equipment basic EMCrecommendation K.35 Bonding configurations and earthing at remote electronic sites Selection of protective devices 1< 37 1< 38 K.39 1< 40 K.41 1< 42 1< 43 K.44 K.4S K.46 K.47 K.48 K.49 K.SO K.Sl K.52 K.53 K.54 Low and highfrequency EMC mitigationtecliniquesfor telecommunication installations and systems - basic EMC Recommendation Radiated. e11li~$i()Il testptocedure for physically large systemS Risk assessment of damages to telecommunication.sites due to lightning discharges ProtectionagainstLE1vfP in telecommunication centers Resistibility·ofinternaI interfaces of telecommuni~ation centers to surge overvoltages: Preparation of emission and immunity requirements for telecommunication e~uipmentJ0i~~~eraI ~ri~~iples Iriit11unityrequirements for telecommunication· equipment Resistibility of telecommunication equipment.toovervoltages •••• and overCUJ.TeIlts Resistibility of access· network equipment toovervoltages and overcurrents Protection of telecommunication. lines usingmetal1iesymmetriCconductors· against lightriing-induced surges Protection of telecommunication lines using.meta.lli~~onduc~against direct··.lighttUngdischarges EMC requirements for each telecommunication network equipment -product farllily recoriunendation Testcondition "and perfonnance criteria for voice terminalsubject to disturbanceftom digital mobile phone Safe limits of operating voltages and curr~nts fort~!~~mmunicati()~ systems powetedover.tlienelWork Safety criteria for telecommunication equipment (]uida.riceon~omplyirigwithlimits for hUll1anexpo8Ute to electromagnetic fields Values of induced voltages on telecommunication installations to establish telecommunications, AC power, and railway operators responsibilities Conducted immunitytestmethod and levelatfundarptrnta1 pow~r frequencies 551 © 2003 by CRC Press LLC . commerce beans for the Java Wallet. JOTP servers are based upon the Enter- prise JavaBean and Servlet component models. Inter- operability is through XML-based Open Trading Pro- tocol transaction transport mechanisms. joule (symb. - 1) An absolute meter-kilogram-second (MKS) unit. boxA wire or fiber optic encasement box for coupling cables. It is often made of metal or 545 © 2003 by CRC Press LLC Fiber Optics Illustrated Dictionary other moisture- or fire-retardant materials, and is commonly found in homes and businesses. Junction boxes are frequently hidden in closets or attached to the sides of buildings near a utility/network drop. They are crucial to most wire and fiber transmission technologies. Every time a transmission link is interrupted, split, joined, amplified, or otherwise affected at a wiring junction, there is the possibility of damage, short circuits, noise, or loss of signal. The main functions of the junction box are to protect the wiring from moisture, heat, or other conditions that may damage the wires or fiber filaments or short an electrical circuit, to provide. equipment on end poles, or conduits for connecting an end pole with underground wiring. A grounding rod at the base of the pole may be used to ground the MGN. 543 © 2003 by CRC Press LLC Fiber Optics Illustrated Dictionary stock market that is particularly

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