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designation, would have been terrestrial with no TASI or DCME, and the C6 signalling on the data link could perform for 48 or 96 traffic channels. It could function for up to 2,048 in the maximum. The question is whether two operators would have that many traffic channels between them, dependent on
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were slowly beginning to exceed these data rates over 4w circuits; these data links had the advantage that there was no national tail from the ISC out to a normal end point in the country. It was often the
National Section that detracted the most from the quality and reliability of such links.
186:. Taking the signalling function away from the traffic channel could cut costs, and would later lead to Common Channel Signalling. There would be no need for filtering signalling away from speech, and the duty cycle of the costly trunk for each revenue earning call would be better. Signalling
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Finally it was considered possible that a mesh of such data channels could be set up between major centres, leading to a system where the link between country A and country B could perform the signalling functions for links to country A from country D for example.
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just one bearer for signalling and subject to occasional failure. It was of course practice to have standby route over a diverse path in case of outage on the original DP data circuit link.
240:
telephone calls. The next development was correspondent and non-correspondent switching of telephone calls by new operators in the countries where more sophisticated methods were required.
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CCITT No 6 was a method developed & implemented by administrations in a limited number of countries for use in correspondent
International Switching of
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The system had limited applications since at that time the predecessor systems
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between international switching centers (ISCs). It is specified in
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channels. In some cases these were advantaged or multiplied with
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Traffic switching in the ISCs was then typically handled by
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208:. Technology at the time was an M1040 or M1020 analogue
178:(DCME). These transmission methods were not suited to
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201:The CCITT 6 signalling channel was typically a 2.4
46:. Unsourced material may be challenged and removed.
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154:or electronically controlled cross-points such as
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1372:Global telecommunications regulation bodies
275:- Specifications of Signalling System No. 6
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125:) was introduced in the 1970s as an early
106:Learn how and when to remove this message
176:digital circuit multiplication equipment
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172:time-assignment speech interpolation
44:adding citations to reliable sources
15:
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1007:Free-space optical communication
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273:ITU-T Recommendation Q.251-Q.300
250:
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31:needs additional citations for
1465:Signaling (telecommunications)
224:The data circuit known with a
1:
243:
140:Recommendations Q.251-Q.300.
132:method for telecommunication
1393:Telecommunication portal
1174:Telecommunications equipment
305:. You can help Knowledge by
7:
910:Alexander Stepanovich Popov
10:
1609:
614:Telecommunications history
284:
166:links or long terrestrial
1554:
1531:Multi-frequency signaling
1526:Dual-tone multi-frequency
1471:
1381:
1323:
1260:
1222:Public Switched Telephone
1182:
1146:
1103:
1044:
1034:telecommunication circuit
995:Fiber-optic communication
978:
740:Francis Blake (telephone)
687:
535:Optical telecommunication
379:
1583:Telecommunications stubs
1506:Special information tone
1133:Orbital angular-momentum
570:Satellite communications
409:Communications satellite
297:This article related to
55:"Signaling System No. 6"
1546:Signalling System No. 7
1541:Signalling System No. 6
1012:Molecular communication
835:Gardiner Greene Hubbard
664:Undersea telegraph line
399:Cable protection system
1536:Signaling System No. 5
1154:Communication protocol
940:Charles Sumner Tainter
755:Walter Houser Brattain
700:Edwin Howard Armstrong
508:Information revolution
145:Signaling System No. 5
119:Signaling System No. 6
1588:ITU-T recommendations
1564:Telephones portal
1128:Polarization-division
860:Narinder Singh Kapany
825:Erna Schneider Hoover
745:Jagadish Chandra Bose
725:Alexander Graham Bell
456:online video platform
970:Vladimir K. Zworykin
930:Almon Brown Strowger
900:Charles Grafton Page
555:Prepaid mobile phone
483:Electrical telegraph
40:improve this article
920:Johann Philipp Reis
679:Wireless revolution
641:The Telephone Cases
498:Hydraulic telegraph
188:time in call set up
184:register signalling
1118:Frequency-division
1095:Telephone exchange
965:Charles Wheatstone
895:Jun-ichi Nishizawa
870:Innocenzo Manzetti
805:Reginald Fessenden
540:Optical telegraphy
373:Telecommunications
299:telecommunications
160:transmission media
1593:Telephony signals
1570:
1569:
1431:
1430:
1169:Store and forward
1164:Data transmission
1078:Network switching
1029:Transmission line
875:Guglielmo Marconi
840:Internet pioneers
705:Mohamed M. Atalla
674:Whistled language
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258:Telephones portal
210:Four-wire circuit
152:crossbar switches
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1262:Notable networks
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1192:Cellular network
1184:Types of network
1159:Computer network
1046:Network topology
960:Thomas A. Watson
815:Oliver Heaviside
800:Philo Farnsworth
775:Daniel Davis Jr.
750:Charles Bourseul
710:John Logie Baird
419:Data compression
414:Computer network
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587:Semiconductor
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57: –
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51:Find sources:
45:
41:
35:
34:
29:This article
27:
23:
18:
17:
1496:Reorder tone
1486:Ringing tone
1105:Multiplexing
980:Transmission
945:Nikola Tesla
935:Henry Sutton
890:Samuel Morse
820:Robert Hooke
785:Amos Dolbear
720:John Bardeen
639:
619:Telautograph
523:Mobile phone
478:Edholm's law
461:social media
394:Broadcasting
307:expanding it
296:
281:
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235:
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223:
200:
162:were likely
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122:
118:
117:
102:
96:January 2011
93:
83:
76:
69:
62:
50:
38:Please help
33:verification
30:
1491:Busy signal
1305:NPL network
1017:Radio waves
955:Alfred Vail
865:Hedy Lamarr
850:Dawon Kahng
810:Elisha Gray
770:Yogen Dalal
695:Nasir Ahmed
629:Teleprinter
493:Heliographs
156:reed relays
1577:Categories
1351:Antarctica
1310:Toasternet
1232:Television
715:Paul Baran
647:Television
631:(teletype)
624:Telegraphy
602:transistor
580:Phryctoria
550:Photophone
528:Smartphone
518:Mass media
244:References
212:presented
192:clear down
174:(TASI) or
130:signalling
66:newspapers
1476:Dial tone
1335:Americas
1324:Locations
1295:Internet2
1056:Bandwidth
760:Vint Cerf
657:streaming
635:Telephone
575:Semaphore
466:streaming
206:data link
182:or inter-
164:satellite
1516:Zip tone
1481:Ringtone
1403:Category
1290:Internet
1280:CYCLADES
1197:Ethernet
1147:Concepts
1071:terminal
1022:wireless
845:Bob Kahn
688:Pioneers
513:Internet
404:Cable TV
238:analogue
1521:2600 Hz
1423:Commons
1413:Outline
1366:Oceania
1285:FidoNet
1270:ARPANET
1083:circuit
652:digital
381:History
80:scholar
1361:Europe
1331:Africa
1315:Usenet
1275:BITNET
1212:Mobile
1088:packet
597:MOSFET
592:device
389:Beacon
218:Modems
216:link.
203:kbit/s
158:. The
134:trunks
82:
75:
68:
61:
53:
1344:South
1339:North
1300:JANET
1237:Telex
1227:Radio
1066:Nodes
1061:Links
982:media
560:Radio
545:Pager
473:Drums
439:video
434:image
424:audio
301:is a
196:fraud
138:CCITT
87:JSTOR
73:books
1356:Asia
1242:UUCP
1202:ISDN
303:stub
190:and
180:line
59:news
1247:WAN
1217:NGN
1207:LAN
488:Fax
429:DCT
123:SS6
42:by
1579::
226:DP
1457:e
1450:t
1443:v
1374:)
1370:(
365:e
358:t
351:v
334:e
327:t
320:v
309:.
121:(
109:)
103:(
98:)
94:(
84:·
77:·
70:·
63:·
36:.
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