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| The following
is a glossary of terms you're likely to come across as you get ready
bandwidth: The amount of data hat cable can carry from computer to computer. Category 5 cable, which is the state of the art in high-bandwidth cable, carries data at rates of up to 100 megabits per second. You may have seen a video clip played from a CD-ROM. Video data takes up more room, or bandwidth, as it travels over cable than other kinds of data. To play the video clip you saw, the computer needed to send data from the CD-ROM to the screen at 150 to 600 kilobytes per second, or only a fraction of the rate that data can travel over Category 5 cable. So, for instance, if there were only high-bandwidth cable between California schools and schools in Japan - and no low-bandwidth bottlenecks - a student in a schoolroom in Chattanooga could see live video of a pen-pal in Osaka.
box: A metal or plastic box, surface or flush mounted, behind an electrical receptacle like a jack or light switch. It encloses the wiring and, if the wiring catches fire, helps prevent the fire from spreading.
bulletin board service or BBS: A service that lets people make announcements, upload or download files and leave each other messages by computer. BBSs are different from the Internet in that you access them through the telephone network only, not through a computer network like Internet. There are many of them, mostly very small and run from just one computer.
Category 5 cable: Eight standard copper telephone wires, encased in a plastic sheath. The wires are color-coded to match corresponding slots in jacks and patch panels: blue and blue/white, orange and orange/white, green and green/white and brown and brown/white. Color/white wires may be striped blue and white, orange and white, etc., or they may just be white. The wires are twisted inside the sheath in a way that used for data transmission. It costs about 13 cents a foot at computer supply stores.
channel locks Brand name for adjustable pliers.
data: Just as S.O.S. signals say things with dots and dashes, computers "talk" using two kinds of electrical signals: high and low. A stream of these signals put together in an order that a computer can read is called data.
data closet or telecommunications closet: A closet that houses a patch panel and possibly other equipment. The central point at your school may not necessarily be inside a closet.
drywall saw: See saws.
EIA 568A specification: The Electronic Industries Association spec for installing Category 5 cable that allows the cable to transmit 100 megabits per second. Among other details, it specifies that cable runs must not be longer than 328 feet (100 meters), including any service coil or patch cords. Longer stretches of cable will slow the transmission of data over the network.
gutter: See raceway.
the Internet or the Net: A kind of wide area network. Just as sound is transmitted around the world from telephone to telephone over a network of wire and cable, electronic data is transmitted around the world from computer to computer by wire, cable and other means. The largest of such networks is called the Internet. The United States military developed the Internet in the 1960s. Universities began using it widely in the 1970s, and in the last few years the Internet has exploded into use in homes, schools and businesses around the world. Through the Internet, people can use computers to transmit digitized text, sound, pictures and movies. Different ways that data can be sent over the Internet include e-mail, file transfer, newsgroups and the World Wide Web. Voice transmission software lets people talk to each other through their Internet connections as if they were on the telephone.
Internet service provider or ISP: A company, such as Netcom or MCI or the WELL, that provides access to the Internet through a modem or faster connection. which in turn connects them to the Internet.
ISDN (integrated services digital network) line: A phone line configured to transmit data at high speeds.
jig saw: See saws.
keyhole saw: See saws.
LAN or local area network: See network.
low-voltage current: Buildings have two sets of wires, one for 120-volt power and anotherfor 12-volt signals. The 120-volt set powers appliances and most lighting. The 12-volt setcarries things like thermostat signals and computer data. It has very little amperage, so you canwire it without boxes, circuit breakers or fuses.
megabit or Mb: A million bits. A bit is the most basic unit that computers use to talk; it's a unit of electronic data equal to the choice between on and off. Category 5 cable transmits up to 100 megabits per second. See bandwidth.
mud ring: Same as low-voltage mounting bracket.
network: Links between two or more computers that let the computers exchange information. Networks usually include a server, which acts as a hub for all the other computers. A local area network, or LAN, is a group of linked computers in a school or business. The Internet is one kind of wide area network; America Online, CompuServe and the WELL are others.
on-line service: A service, such as CompuServe or America Online, that provides access to a network of information, services and a community of other subscribers as well as to the Internet.
patch panel: An assembly of pin locations and ports, mounted on a rack or wall bracket. A patch panel acts like a switchboard where cable from schoolrooms can be connected to each other (forming a local network) and to the outside (linking to the Internet or other wide area network). Krone and 110 are the names of two kinds of patch panels; Krones are made by Krone, and 110s are made by many companies. The patch panel in each NetDay kit has 24 ports and enough pin locations to wire 24 cables.
plate: See wall plate.
raceway, decorative raceway and gutter: Raceway is a wall-mounted channel with a removable top. Decorative raceway (also known by the brand name Wiremold) is big enough to hold two cables; it's used to mount cable against a wall. Raceway big enough to hold many cables is sometimes called gutter; it's used in ceilings and attics. Made of plastic or metal, raceway mounts with screws or an adhesive backing.
reciprocating: saw. See saws.
RJ45 jack: The kind of jack in your NetDay kit, for making up a connection to Category 5 cable. It consists of color-coded slots, into which you'll "punch down" wires to make an electrical connection, and a female plug. The plug looks like a standard phone jack but with eight pins instead of four. You can plug a standard phone cord into the middle four pins of an RJ45 jack.
rotary drill: Same as hammer drill.
run: The path of a length of cable from the central point to a schoolroom.
saws: A drywall saw is a hand saw for making cutouts in drywall. A jigsaw is a machine saw for making precise cutouts. A keyhole saw is a hand saw for making small holes in wood such as baseboard, paneling and lath. A reciprocating saw is a machine saw for rough-cutting wood and metal.
server: A computer used to manage file storage and traffic in a network.
Sheetrock: A brand name for drywall.
slip-joint pliers: Same as adjustable pliers.
T-bar: See dropped ceiling.
telecommunications closet: Same as data closet.
tie-wrap: A plastic tie for holding cables together or holding cable in place. One use of tie-wrap is to cinch cable to the wires that suspend a dropped ceiling. "Holey" tie-wraps have holes for screws to attach cable to a wall. Tie-wraps are also sold with adhesive-backed patches.
UTP (unshielded twisted pair) cable: Same as Category 5 cable.
wide area network: See network.
Wiremold: Brand name for decorative raceway.