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by New York
Telephone. As of 2003, it was estimated that there were 20 million Centrex lines installed worldwide by 20 telephone companies, with the most installations in the United States (15 million), Canada (2 million), and the United Kingdom (1 million). This accounted for approximately 5% of
147:
In the United States, the usage of
Centrex lines has fallen from 16.5 million in 2002 to 10.7 million in 2008 as users transition to IP-PBX (through VoIP). Centrex continues to be used by large institutions, government agencies, and universities as most of the equipment has already been paid for,
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19:
This article is about the type of telephone exchange. For the
British police training agency, see
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866:
801:
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369:
108:
86:
70:
Typical standard phone used with
Centrex. Note the "Recall" button and the Message Waiting Lamp.
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1025:
911:
871:
701:
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93:, but is provisioned with equipment owned by, and located at, the telephone company premises.
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49:
Please help update this article to reflect recent events or newly available information.
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In terms of user-visible features, Centrex and PBX are similar. Features include:
317:. The Telecommunications Industry Association. 2009. pp. 3–20. Archived from
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Centrex service was first installed in the early 1960s in
203:. Artech House. Chapter 1, Introduction to Centrex.
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though leasing
Centrex lines may be more expensive.
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255:. John Wiley & Sons. Section 3.3.1 (Features).
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101:all installed business telephone lines, worldwide.
23:. For the Gazprom-related group of companies, see
114:Automatic routing of calls to obtain lowest cost
354:
8:
1369:Global telecommunications regulation bodies
312:"TIA'S 2009 ICT MARKET REVIEW AND FORECAST"
1405:
361:
347:
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197:Abrahams, John R.; Lollo, Mauro (2003).
157:
168:Understanding Voice Over IP Technology
89:. It provides functions similar to a
7:
1415:
192:
190:
188:
1441:Telephone service enhanced features
165:Wittenberg, Nicholas (2009-02-19).
25:Centrex Europe Energy & Gas AG
14:
171:. Cengage Learning. p. 367.
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1395:
1394:
1383:
1004:Free-space optical communication
278:"Centrex: It's alive (for now)!"
276:Reed, Brad (February 13, 2012).
200:Centrex Or PBX: The Impact of IP
34:
21:Centrex (police training agency)
1:
98:New York's financial district
1390:Telecommunication portal
1171:Telecommunications equipment
907:Alexander Stepanovich Popov
131:Automatic call distribution
1462:
611:Telecommunications history
18:
16:Telephone exchange service
1378:
1219:Public Switched Telephone
1031:telecommunication circuit
992:Fiber-optic communication
737:Francis Blake (telephone)
532:Optical telecommunication
249:Horak, Ray (2012-11-19).
43:This article needs to be
1130:Orbital angular-momentum
567:Satellite communications
406:Communications satellite
225:"Telephony 101: Centrex"
1009:Molecular communication
832:Gardiner Greene Hubbard
661:Undersea telegraph line
396:Cable protection system
288:(3): 10. Archived from
229:The Museum of Telephony
1151:Communication protocol
937:Charles Sumner Tainter
752:Walter Houser Brattain
697:Edwin Howard Armstrong
505:Information revolution
71:
1125:Polarization-division
857:Narinder Singh Kapany
822:Erna Schneider Hoover
742:Jagadish Chandra Bose
722:Alexander Graham Bell
453:online video platform
137:Call detail recording
109:Direct inward dialing
69:
967:Vladimir K. Zworykin
927:Almon Brown Strowger
897:Charles Grafton Page
552:Prepaid mobile phone
480:Electrical telegraph
77:is a portmanteau of
1446:Telephone exchanges
917:Johann Philipp Reis
676:Wireless revolution
638:The Telephone Cases
495:Hydraulic telegraph
117:Call pick-up groups
1115:Frequency-division
1092:Telephone exchange
962:Charles Wheatstone
892:Jun-ichi Nishizawa
867:Innocenzo Manzetti
802:Reginald Fessenden
537:Optical telegraphy
370:Telecommunications
126:Conference calling
87:telephone exchange
85:change, a kind of
72:
1428:
1427:
1166:Store and forward
1161:Data transmission
1075:Network switching
1026:Transmission line
872:Guglielmo Marconi
837:Internet pioneers
702:Mohamed M. Atalla
671:Whistled language
64:
63:
1453:
1418:
1417:
1408:
1407:
1398:
1397:
1388:
1387:
1386:
1259:Notable networks
1249:Wireless network
1189:Cellular network
1181:Types of network
1156:Computer network
1043:Network topology
957:Thomas A. Watson
812:Oliver Heaviside
797:Philo Farnsworth
772:Daniel Davis Jr.
747:Charles Bourseul
707:John Logie Baird
416:Data compression
411:Computer network
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978:
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877:Robert Metcalfe
732:Tim Berners-Lee
680:
500:Information Age
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121:Call forwarding
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1110:Space-division
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989:
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959:
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947:Camille Tissot
944:
939:
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929:
924:
922:Claude Shannon
919:
914:
912:Tivadar Puskás
909:
904:
899:
894:
889:
884:
882:Antonio Meucci
879:
874:
869:
864:
859:
854:
852:Charles K. Kao
849:
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827:Harold Hopkins
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727:Emile Berliner
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666:Videotelephony
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562:Radiotelephone
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448:Internet video
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292:on 3 July 2013
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1142:
1136:
1135:Code-division
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1128:
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1123:
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1120:Time-division
1118:
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1111:
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1048:
1046:and switching
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1027:
1024:
1020:
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1016:
1015:
1012:
1010:
1007:
1005:
1002:
998:
997:optical fiber
995:
994:
993:
990:
988:
987:Coaxial cable
985:
984:
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980:
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902:Radia Perlman
900:
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800:
798:
795:
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792:Lee de Forest
790:
788:
787:Thomas Edison
785:
783:
780:
778:
777:Donald Davies
775:
773:
770:
768:
765:
763:
762:Claude Chappe
760:
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614:
612:
609:
607:
606:Smoke signals
604:
600:
597:
595:
592:
590:
587:
586:
585:
584:Semiconductor
582:
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443:Digital media
441:
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324:on 2018-05-21
320:
313:
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291:
287:
283:
282:Network World
279:
272:
269:
264:
262:9781118585801
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210:9781580536226
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178:9781111806613
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46:
41:
32:
31:
26:
22:
1102:Multiplexing
977:Transmission
942:Nikola Tesla
932:Henry Sutton
887:Samuel Morse
817:Robert Hooke
782:Amos Dolbear
717:John Bardeen
636:
616:Telautograph
520:Mobile phone
475:Edholm's law
458:social media
391:Broadcasting
326:. Retrieved
319:the original
306:
294:. Retrieved
290:the original
285:
281:
271:
251:
244:
233:. Retrieved
231:. 2016-07-09
228:
219:
199:
167:
160:
146:
103:
95:
82:
78:
74:
73:
52:
44:
1302:NPL network
1014:Radio waves
952:Alfred Vail
862:Hedy Lamarr
847:Dawon Kahng
807:Elisha Gray
767:Yogen Dalal
692:Nasir Ahmed
626:Teleprinter
490:Heliographs
296:22 February
143:Phasing out
1435:Categories
1348:Antarctica
1307:Toasternet
1229:Television
712:Paul Baran
644:Television
628:(teletype)
621:Telegraphy
599:transistor
577:Phryctoria
547:Photophone
525:Smartphone
515:Mass media
328:2012-02-22
235:2019-01-04
152:References
1332:Americas
1321:Locations
1292:Internet2
1053:Bandwidth
757:Vint Cerf
654:streaming
632:Telephone
572:Semaphore
463:streaming
55:July 2019
1400:Category
1287:Internet
1277:CYCLADES
1194:Ethernet
1144:Concepts
1068:terminal
1019:wireless
842:Bob Kahn
685:Pioneers
510:Internet
401:Cable TV
1420:Commons
1410:Outline
1363:Oceania
1282:FidoNet
1267:ARPANET
1080:circuit
649:digital
378:History
75:Centrex
45:updated
1358:Europe
1328:Africa
1312:Usenet
1272:BITNET
1209:Mobile
1085:packet
594:MOSFET
589:device
386:Beacon
259:
207:
175:
1341:South
1336:North
1297:JANET
1234:Telex
1224:Radio
1063:Nodes
1058:Links
979:media
557:Radio
542:Pager
470:Drums
436:video
431:image
421:audio
322:(PDF)
315:(PDF)
133:(ACD)
111:(DID)
79:centr
1353:Asia
1239:UUCP
1199:ISDN
298:2012
257:ISBN
205:ISBN
173:ISBN
1244:WAN
1214:NGN
1204:LAN
485:Fax
426:DCT
91:PBX
81:al
1437::
286:29
284:.
280:.
227:.
187:^
83:ex
1371:)
1367:(
362:e
355:t
348:v
331:.
300:.
265:.
238:.
213:.
181:.
57:)
53:(
47:.
27:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
