1、 I n t e r n a t i o n a l T e l e c o m m u n i c a t i o n U n i o n ITU-T G.993.2 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Corrigendum 1 (11/2016) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Digital sections and digital line system Metallic access networks Very h
2、igh speed digital subscriber line transceivers 2 (VDSL2) Corrigendum 1 Recommendation ITU-T G.993.2 (2016) Corrigendum 1 ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS INTERNATIONAL TELEPHONE CONNECTIONS AND CIRCUITS G.100G.199 GENERAL CHARACTERISTICS COM
3、MON TO ALL ANALOGUE CARRIER-TRANSMISSION SYSTEMS G.200G.299 INDIVIDUAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON METALLIC LINES G.300G.399 GENERAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON RADIO-RELAY OR SATELLITE LINKS AND INTERCONNECTION WITH METALLIC LINES
4、G.400G.449 COORDINATION OF RADIOTELEPHONY AND LINE TELEPHONY G.450G.499 TRANSMISSION MEDIA AND OPTICAL SYSTEMS CHARACTERISTICS G.600G.699 DIGITAL TERMINAL EQUIPMENTS G.700G.799 DIGITAL NETWORKS G.800G.899 DIGITAL SECTIONS AND DIGITAL LINE SYSTEM G.900G.999 General G.900G.909 Parameters for optical f
5、ibre cable systems G.910G.919 Digital sections at hierarchical bit rates based on a bit rate of 2048 kbit/s G.920G.929 Digital line transmission systems on cable at non-hierarchical bit rates G.930G.939 Digital line systems provided by FDM transmission bearers G.940G.949 Digital line systems G.950G.
6、959 Digital section and digital transmission systems for customer access to ISDN G.960G.969 Optical fibre submarine cable systems G.970G.979 Optical line systems for local and access networks G.980G.989 Metallic access networks G.990G.999 MULTIMEDIA QUALITY OF SERVICE AND PERFORMANCE GENERIC AND USE
7、R-RELATED ASPECTS G.1000G.1999 TRANSMISSION MEDIA CHARACTERISTICS G.6000G.6999 DATA OVER TRANSPORT GENERIC ASPECTS G.7000G.7999 PACKET OVER TRANSPORT ASPECTS G.8000G.8999 ACCESS NETWORKS G.9000G.9999 For further details, please refer to the list of ITU-T Recommendations. Rec. ITU-T G.993.2 (2015)/Co
8、r.1 (11/2016) i Recommendation ITU-T G.993.2 Very high speed digital subscriber line transceivers 2 (VDSL2) Corrigendum 1 Summary Recommendation ITU-T G.993.2 specifies an access technology that exploits the existing infrastructure of copper wires that were originally deployed for POTS services. It
9、can be deployed from central offices, from fibre-fed cabinets located near customer premises, or within buildings. This Recommendation is an enhancement to ITU T G.993.1 that supports asymmetric and symmetric transmission at a bidirectional net data rate up to 200 Mbit/s on twisted pairs using a ban
10、dwidth up to 30 MHz. This version of this Recommendation integrates all the previous amendments and corrigenda with the 2011 version of Recommendation ITU-T G.993.2. Amendment 2 to Recommendation ITU-T G.993.2 (2015) defines the new functionality: Method to address the misestimation of the SNR durin
11、g MEDLEY. Corrigendum 1 covers the following functionality: 1. Segmentation of SOC messages for profile 35b (corrigendum). History Edition Recommendation Approval Study Group Unique ID* 1.0 ITU-T G.993.2 2006-02-17 15 11.1002/1000/8548 1.1 ITU-T G.993.2 (2006) Cor. 1 2006-12-14 15 11.1002/1000/8992
12、1.2 ITU-T G.993.2 (2006) Amd. 1 2007-04-06 15 11.1002/1000/8991 1.3 ITU-T G.993.2 (2006) Amd. 1 Cor. 1 2007-07-29 15 11.1002/1000/9164 1.4 ITU-T G.993.2 (2006) Cor. 2 2007-07-29 15 11.1002/1000/9166 1.5 ITU-T G.993.2 (2006) Amd. 2 2008-02-06 15 11.1002/1000/9165 1.6 ITU-T G.993.2 (2006) Amd. 3 2008-
13、08-22 15 11.1002/1000/9387 1.7 ITU-T G.993.2 (2006) Amd. 4 2009-01-13 15 11.1002/1000/9654 1.8 ITU-T G.993.2 (2006) Cor. 3 2009-06-29 15 11.1002/1000/9890 1.9 ITU-T G.993.2 (2006) Amd. 5 2010-04-22 15 11.1002/1000/10413 1.10 ITU-T G.993.2 (2006) Amd. 6 2010-11-29 15 11.1002/1000/11022 1.11 ITU-T G.9
14、93.2 (2006) Cor. 4 2011-04-13 15 11.1002/1000/11149 1.12 ITU-T G.993.2 (2006) Amd. 7 2011-06-22 15 11.1002/1000/11148 2.0 ITU-T G.993.2 2011-12-16 15 11.1002/1000/11415 2.1 ITU-T G.993.2 (2011) Amd. 1 2012-04-06 15 11.1002/1000/11502 2.2 ITU-T G.993.2 (2011) Cor. 1 2012-06-13 15 11.1002/1000/11642 2
15、.3 ITU-T G.993.2 (2011) Amd. 2 2012-12-07 15 11.1002/1000/11795 2.4 ITU-T G.993.2 (2011) Amd. 3 2013-04-22 15 11.1002/1000/11888 2.5 ITU-T G.993.2 (2011) Amd. 4 2013-08-29 15 11.1002/1000/11992 2.6 ITU-T G.993.2 (2011) Amd. 5 2014-01-13 15 11.1002/1000/12096 2.7 ITU-T G.993.2 (2011) Amd. 6 2015-05-2
16、2 15 11.1002/1000/12371 3.0 ITU-T G.993.2 2015-01-13 15 11.1002/1000/12370 3.1 ITU-T G.993.2 (2015) Amd. 1 2015-11-06 15 11.1002/1000/12563 3.2 ITU-T G.993.2 (2015) Amd. 2 2016-03-29 15 11.1002/1000/12796 3.3 ITU-T G.993.2 (2015) Cor.1 2016-11-13 15 11.1002/1000/13120 _ * To access the Recommendatio
17、n, type the URL http:/handle.itu.int/ in the address field of your web browser, followed by the Recommendations unique ID. For example, http:/handle.itu.int/11.1002/1000/11830-en. ii Rec. ITU-T G.993.2 (2015)/Cor.1 (11/2016) FOREWORD The International Telecommunication Union (ITU) is the United Nati
18、ons specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations
19、on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of
20、 ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is
21、 used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with
22、 the Recommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required
23、 of any party. INTELLECTUAL PROPERTY RIGHTSITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual
24、Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, ITU had received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, im
25、plementers are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2017 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior wri
26、tten permission of ITU. Rec. ITU-T G.993.2 (2015)/Cor.1 (11/2016) iii Table of Contents Page 1 Scope . 1 2 References . 3 3 Definitions 4 4 Abbreviations and acronyms 8 5 Reference models 11 5.1 VTU functional model 11 5.2 User plane protocol reference model 13 5.3 Management plane reference model .
27、 14 5.4 Application reference models . 15 6 Profiles 19 6.1 Definition 19 6.2 Profile parameter definitions 23 6.3 Profile compliance 26 7 Transmission medium interface characteristics 27 7.1 Duplexing method and band plan construction 27 7.2 Power spectral density (PSD) . 28 7.3 Termination impedan
28、ce 44 7.4 Longitudinal conversion loss 44 8 Transport protocol specific transmission convergence (TPS-TC) function . 45 8.1 The user data TPS-TC 45 8.2 Management TPS-TC (MPS-TC) . 47 8.3 Network timing reference TPS-TC (NTR-TC) 51 8.4 Time-of-day TPS-TC (ToD-TC) 52 9 Physical media specific transmi
29、ssion convergence (PMS-TC) sublayer . 59 9.1 PMS-TC functional model . 59 9.2 Scrambler 62 9.3 Forward error correction . 62 9.4 Interleaving . 63 9.5 Framing . 65 9.6 Impulse noise protection (INPp) . 74 9.7 Delay . 75 9.8 Bit error ratio (BER) . 76 9.9 Delay variation . 76 10 Physical media depend
30、ent (PMD) function 76 10.1 PMD functional model . 76 10.2 DMT superframe 77 iv Rec. ITU-T G.993.2 (2015)/Cor.1 (11/2016) Page 10.3 Symbol encoder for data symbols 78 10.4 Modulation . 92 10.5 Symbol encoder for sync symbol . 96 10.6 Symbol encoder for initialization . 96 11 Operation and maintenance
31、 (OAM) . 97 11.1 OAM functional model . 97 11.2 VDSL2 management entity (VME) 99 11.3 OAM primitives 134 11.4 OAM parameters 137 11.5 Data gathering function 172 12 Link activation methods and procedures 184 12.1 Overview 184 12.2 Special operations channel (SOC) 192 12.3 Initialization procedure .
32、196 12.4 Loop diagnostic mode procedures 286 12.5 Fast start-up 295 13 On-line reconfiguration (OLR) . 295 13.1 Types of on-line reconfiguration 295 13.2 Control parameters . 296 13.3 Timing of changes in subcarrier configuration 298 13.4 Receiver initiated procedure . 300 14 Electrical requirements
33、 . 303 14.1 Termination impedance model . 303 14.2 Service splitters 303 Annex A Region A (North America) 305 A.1 Band plan 305 A.2 Limit PSD masks 305 A.3 UPBO reference PSDs 313 Annex B Region B (Europe) . 314 B.1 Band plans 314 B.2 Limit PSD mask options . 317 B.3 UPBO reference PSDs 333 B.4 Temp
34、late PSD . 333 B.5 Compliance . 333 Annex C Region C (Japan) . 334 C.1 Band plan 334 C.2 Limit PSD masks 334 C.3 VDSL2 system with PSD reduction at frequencies below DPBOFMAX 343 C.4 Upstream power back-off (UPBO) PSD masks . 343 Rec. ITU-T G.993.2 (2015)/Cor.1 (11/2016) v Page C.5 Service Splitter
35、. 344 C.6 Test loops and crosstalk disturbers . 344 Annex D 346 Annex E 346 Annex F 346 Annex G 346 Annex H 346 Annex J 346 Annex K 346 Annex L TPS-TC functional descriptions . 347 L.1 STM transmission convergence (STM-TC) function . 347 L.2 ATM transmission convergence (ATM-TC) function . 353 L.3 P
36、acket transmission convergence function (PTM-TC) 363 Annex M Time-of-day distribution over VDSL2 links 369 M.1 Time-of-day distribution operational overview 369 M.2 Definitions 369 M.3 Abbreviations . 369 M.4 VTU functional model 369 M.5 TPS-TC function 369 M.6 eoc communication protocol 369 M.7 ToD
37、 TPS-TC (ToD-TC) . 369 M.8 Mapping of OH data . 369 M.9 eoc transmission protocol . 369 M.10 Frequency synchronization command 369 M.11 Time synchronization command and responses . 371 M.12 Updates to initialization 371 Annex N Region D (China) 372 N.1 Band plans 372 N.2 Limit PSD mask options . 374
38、 Annex O 379 Annex P Short reach VDSL2 with reduced power and enhanced data rate 380 P.1 Scope 380 P.2 Reduced ATP 380 P.3 Minimum bidirectional net data rate capability 380 P.4 ITU-T G.998.4 Annex D support for enhanced net data rates with ITU-T G.998.4 . 380 P.5 SRA support . 381 P.6 TPS-TC . 381
39、vi Rec. ITU-T G.993.2 (2015)/Cor.1 (11/2016) Page Annex Q Enhanced data rate 35 MHz VDSL2 with 4.3125 kHz subcarrier spacing . 382 Q.1 Scope 382 Q.2 Capabilities related to the profile . 382 Q.3 ITU-T G.998.4 Annex D support for enhanced net data rates . 383 Q.4 SRA support . 384 Q.5 TPS-TC . 385 Q.
40、6 Additional changes to ITU-T G.993.2 for operation according to profile 35b 385 Annex R 399 Annex S 399 Annex T 399 Annex U 399 Annex V 399 Annex W 399 Annex X ITU-T G.993.5-friendly ITU-T G.993.2 operation in the downstream direction 400 X.1 Power management commands and responses (clause 11.2.3.9
41、) . 400 X.2 Initialization procedure (supplements clause 12.3) 401 Annex Y Full ITU-T G.993.5-friendly ITU-T G.993.2 operation 408 Y.1 Initialization procedure (supplements clause 12.3) 408 Y.2 R-MSG1 (supplements clause 10.3.2.2 of ITU-T G.993.5) 411 Y.3 O-TA_UPDATE (supplements clause 10.4.2.1 of
42、ITU-T G.993.5) 411 Y.4 R-P-VECTOR 2 (replaces clause 10.4.4.5 of ITU-T G.993.5) . 411 Y.5 O-PMS (supplements clause 10.5.2.1 of ITU-T G.993.5) . 412 Y.6 eoc messages for backchannel configuration (replaces clause 8.1 of ITU-T G.993.5) 412 Y.7 Loop diagnostic mode procedures (replaces clause 12.4) 41
43、2 Appendix I Example values of DPBO parameters to protect ADSL2plus for clause C.3 413 I.1 Example PSD parameters . 413 I.2 Example Cable parameters . 413 I.3 Example frequency parameters 414 Appendix II Impact of loop and VTU impedance mismatch on the Hlog accuracy . 415 Bibliography. 418 Rec. ITU-
44、T G.993.2 (2015)/Cor.1 (11/2016) 1 Recommendation ITU-T G.993.2 Very high speed digital subscriber line transceivers 2 (VDSL2) Editorial note: This is a complete-text publication. It integrates Recommendation ITU-T G.993.2 (2015) plus its Amendments 1 and 2, and Corrigendum 1. 1 Scope This Recommend
45、ation is an enhancement to ITU-T G.993.1 that supports transmission at a bidirectional net data rate (the sum of upstream and downstream rates) up to 200 Mbit/s on twisted pairs. This Recommendation is an access technology that exploits the existing infrastructure of copper wires that were originall
46、y deployed for POTS (plain old telephone service). This Recommendation specifies only discrete multi-tone (DMT) modulation and incorporates components from ITU-T G.993.1 (VDSL), ITU-T G.992.3 (ADSL2), and ITU-T G.992.5 (ADSL2 plus). Whilst POTS uses approximately the lowest 4 kHz and ADSL uses appro
47、ximately 2 MHz of the copper wire spectrum, this Recommendation is defined to allow the use of up to 30 MHz of the spectrum. This Recommendation can be deployed from central offices, from fibre-fed cabinets located near the customer premises, or within buildings. The availability of bandwidth up to
48、30 MHz allows ITU-T G.993.2 transceivers to provide reliable high data rate operation on short loops. Without the use of the US0 band, this Recommendation should operate reliably over loop lengths that are similar to those of ITU-T G.993.1, or slightly longer lengths due to the mandatory support of
49、trellis coding. The addition of the US0 band and means to train echo cancellers and time-domain equalizers (TEQs) also allows this Recommendation to provide reliable operation on loops up to approximately 2 500 metres of 26 AWG (0.4 mm). This Recommendation defines a wide range of settings for various parameters (such as bandwidth and transmitter power) that could potentially be supported by a transceiver. Th
