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With the 32-TC-PAM modulation scheme described in
Annexes F and G, symmetric data rates of up to 5,696 kbit/s are permitted on one pair in the optional extended SHDSL mode. Up to four pairs of wires may be bonded using M-pair bonding to produce data rates as high as M5,696 kbit/s. By using
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conditions (more noise or higher rate means decreased reach) and may be up to 3,000 meters. The two pair feature may alternatively be used for increased reach applications by keeping the data rate low. Halving the data rate per pair will provide similar speeds to single pair lines while increasing
157:. Major updates to G.991.2 were released in December 2003. Equipment conforming to the 2003 version of G.991.2 is often referred to by the standard's draft name of G.SHDSL.bis or just SHDSL.bis. The updated G.991.2 features:
68:, cannot be used to allow a telephone line to be shared by both an SHDSL service and a POTS service at the same time. Support of symmetric data rates made SHDSL a popular choice by businesses for
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in 8 kbit/s increments for one pair and 384 kbit/s to 4,624 kbit/s in 16 kbit/s increments for two pairs of wires. The reach varies according to the
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Optional support for dynamic rate repartitioning, allowing flexible change of the SHDSL data rate without service interruption, described in Annex E.10.3
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SHDSL standardized regional variant for Europe and must not be confused with the usage of the term SDSL in North
America to refer to
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recommendation G.991.2. This was first published in
February 2001. SHDSL equipment is also known by the standard's draft name of
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packets. A 'dual bearer' mode allows a mixture of two separate streams (e.g. T1 and ATM) to share the SHDSL bandwidth.
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Optional extensions to allow user data rates up to 5696 kbit/s per pair, described in
Annexes F and G
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38:(SDSL), a data communications technology for equal transmit and receive (i.e. symmetric) data rate over
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ITU-T Recommendation G.991.2: Single-pair high-speed digital subscriber line (SHDSL) transceivers
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transmission scheme, TC-PAM operates at frequencies that include those used by the analog voice
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New payload definitions including
Ethernet packet transfer mode (PTM), described in Annex E.11
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four bonded wire pairs, a single SHDSL interface can transmit up to 22,784 kbit/s.
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symmetric DSL technology defined in ITU-T G.991.1. SHDSL has largely been replaced by
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because of greater bandwidth, less interference and greater utilization.
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193:(ETSI) using the name 'SDSL'. This ETSI variant is compatible with the
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can provide. As opposed to other DSL technologies, SHDSL employs
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Optional support for up to four copper pair connections (M-pair)
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The SHDSL payload may be either 'clear channel' (unstructured),
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directions, from 192 kbit/s to 2,312 kbit/s of
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191:European Telecommunications Standards Institute
149:The industry standard for SHDSL is defined by
28:Single-pair high-speed digital subscriber line
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189:, a variant of SHDSL was standardized by the
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64:(POTS). As such, a frequency splitter, or
54:trellis-coded pulse-amplitude modulation
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126:(full rate or fractional), multiple
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199:symmetric digital subscriber line
36:symmetric digital subscriber line
508:ITU-T G Series Recommendations
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45:, faster than a conventional
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174:SHDSL supersedes the older
111:the error/noise tolerance.
83:SHDSL features symmetrical
62:plain old telephone service
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467:Ethernet in the first mile
135:Asynchronous Transfer Mode
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80:and other data services.
498:Digital subscriber line
247:Digital subscriber line
74:virtual private network
70:private branch exchange
503:ITU-T recommendations
477:Single Pair Ethernet
433:(early CAP variants)
131:Basic Rate Interface
472:Long Reach Ethernet
352:ANSI T1.413 Issue 2
340:ANSI / ETSI / ITU-T
262:ANSI / ETSI / ITU-T
249:(DSL) technologies
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415:G.fast and MGfast
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137:(ATM) cells or
56:(TC-PAM). As a
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424:Proprietary
288:Proprietary
78:web hosting
492:Categories
408:deployment
384:G.lite.bis
333:Asymmetric
93:downstream
85:data rates
66:DSL filter
320:DSL Rings
310:Etherloop
255:Symmetric
47:voiceband
139:Ethernet
89:upstream
58:baseband
455:Related
396:Annex M
379:Annex L
374:Annex J
155:G.SHDSL
133:(BRI),
97:payload
76:(VPN),
72:(PBX),
391:ADSL2+
362:G.lite
187:Europe
40:copper
462:DSLAM
437:RADSL
369:ADSL2
357:G.dmt
305:MSDSL
279:SHDSL
195:ITU-T
180:VDSL2
151:ITU-T
108:noise
50:modem
32:SHDSL
18:SHDSL
442:UDSL
431:ADSL
347:ADSL
315:HVDL
300:SDSL
295:IDSL
269:HDSL
176:HDSL
128:ISDN
106:and
104:rate
101:loop
91:and
185:In
122:or
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124:E1
120:T1
239:e
232:t
225:v
30:(
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