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315:(FITL) systems are functionally equivalent to DLC. FITL accomplishes the same two primary functions DLC was intended for: pair gain and the elimination of electrical constraints due to long metallic loops. FITL architectures vary from simply deploying fibre feeder plants (between central office and remote terminal site) to "
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dc. Electric current values vary with cable length and gauge. A minimum current of around 20 mA dc is required to convey terminal signalling information to the network. There is also a minimum power level required to provide adequate volume for the voice signal. A variety of schemes were implemented
218:(approximately the gauge of pencil lead), which is costly and bulky. The heavy-gauge cables yielded far fewer pairs per cable and led to early congestion in cable routes, especially in bridge crossings and other areas of limited space.
294:(CO). A fibre optic cable or several copper pairs for the whole system from the CO to the DLC remote terminal replace the individual pair previously needed for each loop. DLC remote terminals are typically stored in
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In a typical configuration, DLC remote terminals are installed in new neighbourhoods or buildings as a means of reducing the labour and complexity of installing individual local loops from the customer to the
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to reduce the attenuation of voice signals over long loops. These have detrimental effect to new transmission technologies using the local loop, like
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to power the voice signal on long loops. This requires volumes of auxiliary equipment, many cross wiring points and extensive record-keeping.
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copper wires. A DLC digitizes and multiplexes the individual signals carried by the local loops onto a single datastream on the DLC segment.
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Expense due to cable cost and the associated labour-intensive installation work (especially to solve the specific problems listed above)
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Cable route congestion (inability to add cable due to lack of space, particularly in urban street, bridge, and building conduit)
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Add signal regeneration and signal extension equipment – The comments regarding amplifiers apply here as well.
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Construction challenges (in areas of difficult terrain) when limited cable pairs are already available
309:(DSLAM), both systems then taking advantage of the digital transmission link from the DLC to the CO.
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Long loops, such as those terminating at more than 18,000 feet (5.49 kilometres) from the
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DLC eliminates the need for these remedies by extending closer to the customer the
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long loops offered to signalling and volume levels. They included the following:
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323:" where an optical network unit (ONU) is located at each home.
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185:, pose electrical challenges. When the subscriber goes
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254:which digitises the voice signal for use by the
126:roadside cabinet housing a Remote Integrated
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307:digital subscriber line access multiplexers
189:, a cable pair behaves like a single loop
146:farther than would be possible using only
106:Learn how and when to remove this message
142:transmission to extend the range of the
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214:Use heavy-gauge conductors – Up to 19
161:systems address a number of problems:
130:(RIM) and Customer Multiplexer (CMUX).
165:Electrical constraints on long loops.
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206:before DLC technology to offset the
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346:"RIM Remote Integrated Multiplexer"
168:Insufficient available cable pairs.
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301:With the growth in popularity of
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277:The DLC solution was dubbed "
138:(DLC) is a system which uses
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262:loop caused by distance,
303:digital subscriber line
296:Serving Area Interfaces
159:Subscriber Loop Carrier
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154:Reasons for using DLCs
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55:"Digital loop carrier"
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136:digital loop carrier
40:improve this article
328:Remote concentrator
319:" and, ultimately "
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321:fibre to the home
317:fibre to the curb
313:Fibre in the loop
221:Increase battery
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96:February 2008
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51:Find sources:
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29:This article
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148:twisted pair
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38:Please help
33:verification
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268:attenuation
128:Multiplexer
369:Local loop
333:References
230:amplifiers
144:local loop
66:newspapers
350:Whirlpool
326:See also
279:pair gain
264:impedance
252:line card
208:impedance
195:potential
363:Category
187:off-hook
223:voltage
197:and an
140:digital
124:Telstra
80:scholar
260:analog
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272:noise
216:gauge
87:JSTOR
73:books
270:and
256:PSTN
238:Add
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59:news
244:DSL
42:by
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