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.709/Y.1331 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Amendment 1 (11/2016) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Digital terminal equipments General SERIES Y: GLOBAL INFORMATION INFR
2、ASTRUCTURE, INTERNET PROTOCOL ASPECTS, NEXT-GENERATION NETWORKS, INTERNET OF THINGS AND SMART CITIES Internet protocol aspects Transport Interfaces for the optical transport network Amendment 1 Recommendation ITU-T G.709/Y.1331 (2016) Amendment 1 ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS A
3、ND MEDIA, DIGITAL SYSTEMS AND NETWORKS INTERNATIONAL TELEPHONE CONNECTIONS AND CIRCUITS G.100G.199 GENERAL CHARACTERISTICS COMMON TO ALL ANALOGUE CARRIER-TRANSMISSION SYSTEMS G.200G.299 INDIVIDUAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON METALLIC LINES G.300G.399 GENERAL CHARACT
4、ERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON RADIO-RELAY OR SATELLITE LINKS AND INTERCONNECTION WITH METALLIC LINES 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.7
5、99 General G.700G.709 Coding of voice and audio signals G.710G.729 Principal characteristics of primary multiplex equipment G.730G.739 Principal characteristics of second order multiplex equipment G.740G.749 Principal characteristics of higher order multiplex equipment G.750G.759 Principal character
6、istics of transcoder and digital multiplication equipment G.760G.769 Operations, administration and maintenance features of transmission equipment G.770G.779 Principal characteristics of multiplexing equipment for the synchronous digital hierarchy G.780G.789 Other terminal equipment G.790G.799 DIGIT
7、AL NETWORKS G.800G.899 DIGITAL SECTIONS AND DIGITAL LINE SYSTEM G.900G.999 MULTIMEDIA QUALITY OF SERVICE AND PERFORMANCE GENERIC AND USER-RELATED ASPECTS G.1000G.1999 TRANSMISSION MEDIA CHARACTERISTICS G.6000G.6999 DATA OVER TRANSPORT GENERIC ASPECTS G.7000G.7999 PACKET OVER TRANSPORT ASPECTS G.8000
8、G.8999 ACCESS NETWORKS G.9000G.9999 For further details, please refer to the list of ITU-T Recommendations. Rec. ITU-T G.709/Y.1331 (2016)/Amd.1 (11/2016) i Recommendation ITU-T G.709/Y.1331 Interfaces for the optical transport network Amendment 1 Summary Recommendation ITU-T G.709/Y.1331 defines th
9、e requirements for the optical transport network (OTN) interface signals of the optical transport network, in terms of: OTN hierarchy functionality of the overhead in support of multi-wavelength optical networks frame structures bit rates formats for mapping client signals. Edition 5.0 of this Recom
10、mendation includes the text of Amendments 2, 3, 4, Corrigendum 2 and Erratum 1 to Edition 4.0 of this Recommendation, support for frequency and time synchronisation, addition of Beyond 100 Gbit/s OTU, ODU and OPU frame formats, overhead, ODU multiplexing, client mappings and optical layer terminolog
11、y updates. Edition 5.0 furthermore deleted the OPUk concatenation specifications and the ATM mapping into OPUk specification and changed the TCM ACT and FTFL overhead bytes into EXP overhead bytes. This amendment contains extensions to the fifth edition (06/2016) of Recommendation ITU T G.709/Y.1331
12、, related to the: Addition of paragraph that describes that ITU-T G.798 complements ITU-T G.709 (1) Addition of references to Recommendation ITU-T G.8260 (2) Addition of definitions and conventions that have been included in the past in ITU-T G.870 (3, 5) Deletion and addition of abbreviations (4) A
13、ddition of a sentence that describes that 3R regeneration is used on both sides of an interface interconnecting user and provider administrations and two provider administrations (6) Corrections to the STU, MOTU, SOTUm and MOTUm descriptions (8.1, 8.2, 8.3, 8.4) Addition of a note describing a vendo
14、r specific mode in the GCC0 communication channel deployment (15.7.2.2) Deletion of OTUCn OSMC (15, 15.7.1, 15.7.2.4, 15.7.2.4.1.2) Deletion of reference to concatenation (15.9.2) Aligning the OPUk/OPUflex clock performance requirement in case of BMP based client mapping with ITU-T G.8251 and ITU-T
15、G.798 (17.2, 17.19, 17.12) Clarify the 2-bit alignment when mapping 66-bit blocks into the OPUflex payload area (17.11, 17.12) Changing the minimum number of FlexE signals in a FlexE aware mapping into an OPUflex (17.12) Addition of 25GE client signal (2, 15.9.2.1.1, 17.13, 17.13.1) Deletion of ODUC
16、n HAO reference (20.4.3.1). ii Rec. ITU-T G.709/Y.1331 (2016)/Amd.1 (11/2016) History Edition Recommendation Approval Study Group Unique ID* 1.0 ITU-T G.709/Y.1331 2001-02-09 15 11.1002/1000/5350 1.1 ITU-T G.709/Y.1331 (2001) Amd. 1 2001-11-29 15 11.1002/1000/5629 2.0 ITU-T G.709/Y.1331 2003-03-16 1
17、5 11.1002/1000/6265 2.1 ITU-T G.709/Y.1331 (2003) Amd. 1 2003-12-14 15 11.1002/1000/7060 2.2 ITU-T G.709/Y.1331 (2003) Cor. 1 2006-12-14 15 11.1002/1000/8982 2.3 ITU-T G.709/Y.1331 (2003) Amd. 2 2007-11-22 15 11.1002/1000/9155 2.4 ITU-T G.709/Y.1331 (2003) Cor.2 2009-01-13 15 11.1002/1000/9646 2.5 I
18、TU-T G.709/Y.1331 (2003) Amd. 3 2009-04-22 15 11.1002/1000/9671 3.0 ITU-T G.709/Y.1331 2009-12-22 15 11.1002/1000/10398 3.1 ITU-T G.709/Y.1331 (2009) Cor. 1 2010-07-29 15 11.1002/1000/10875 3.2 ITU-T G.709/Y.1331 (2009) Amd. 1 2010-07-29 15 11.1002/1000/10874 3.3 ITU-T G.709/Y.1331 (2009) Amd. 2 201
19、1-04-13 15 11.1002/1000/11115 4.0 ITU-T G.709/Y.1331 2012-02-13 15 11.1002/1000/11485 4.1 ITU-T G.709/Y.1331 (2012) Cor. 1 2012-10-29 15 11.1002/1000/11776 4.2 ITU-T G.709/Y.1331 (2012) Amd. 1 2012-10-29 15 11.1002/1000/11774 4.3 ITU-T G.709/Y.1331 (2012) Amd. 2 2013-10-22 15 11.1002/1000/11982 4.4
20、ITU-T G.709/Y.1331 (2012) Amd. 3 2014-12-05 15 11.1002/1000/12363 4.5 ITU-T G.709/Y.1331 (2012) Cor. 2 2015-01-13 15 11.1002/1000/12365 4.6 ITU-T G.709/Y.1331 (2012) Amd. 4 2015-01-13 15 11.1002/1000/12364 5.0 ITU-T G.709/Y.1331 2016-06-22 15 11.1002/1000/12789 5.1 ITU-T G.709/Y.1331 (2016) Amd. 1 2
21、016-11-13 15 11.1002/1000/13080 Keywords Client mappings, frame formats, multiplexing, OTN. _ * To access the Recommendation, 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-e
22、n. Rec. ITU-T G.709/Y.1331 (2016)/Amd.1 (11/2016) iii FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a
23、 permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four years, es
24、tablishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of 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
25、standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the
26、 Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with 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 equival
27、ents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required 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 claim
28、ed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual 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 re
29、ceived notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementers 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/
30、ipr/. ITU 2017 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. iv Rec. ITU-T G.709/Y.1331 (2016)/Amd.1 (11/2016) Table of Contents Page 1 Scope . 1 2 References . 1 3 Definitions 3 3.1 Terms defined elsewhere 3
31、 3.2 Terms defined in this Recommendation . 3 4 Abbreviations and acronyms 5 5 Conventions 9 6 Optical transport network interface structure . 10 6.1 Basic signal structure 11 6.2 Information structure for OTN interfaces . 13 7 Multiplexing/mapping principles and bit rates . 17 7.1 Mapping 19 7.2 Wa
32、velength division multiplex . 19 7.3 Bit rates and capacity 19 7.4 ODUk time-division multiplex . 24 8 OTN Interfaces . 31 8.1 Single-OTU (SOTU) interface . 31 8.2 Multi-OTU (MOTU) interface . 31 8.3 Single-OTU with management (SOTUm) interface . 32 8.4 Multi-OTU with management (MOTUm) interface 32
33、 9 Media Element 32 10 OCh and OTSiA . 32 10.1 OCh . 32 10.2 Optical tributary signal assembly (OTSiA) 33 11 Optical transport unit (OTU) 33 11.1 OTUk frame structure . 33 11.2 Scrambling 34 11.3 OTUCn frame structure 34 12 Optical data unit (ODU) . 35 12.1 ODU frame structure 35 12.2 ODU bit rates
34、and bit-rate tolerances . 36 13 Optical payload unit (OPU) 39 14 Overhead information carried over the OSC and OCC 39 15 Overhead description 40 15.1 Types of overhead 44 Rec. ITU-T G.709/Y.1331 (2016)/Amd.1 (11/2016) v Page 15.2 Trail trace identifier and access point identifier definition 45 15.3
35、OTS-O description 47 15.4 OMS-O description 48 15.5 OCh-O and OTSiG-O description 48 15.6 OTU/ODU frame alignment OH description . 50 15.7 OTU OH description 51 15.8 ODU OH description 57 15.9 OPU OH description . 71 16 Maintenance signals 73 16.1 OTS maintenance signals . 74 16.2 OMS maintenance si
36、gnals 74 16.3 OCh and OTiSA maintenance signals 74 16.4 OTU maintenance signals . 75 16.5 ODU maintenance signals 76 16.6 Client maintenance signal . 78 17 Mapping of client signals 78 17.1 OPU client signal fail (CSF) . 79 17.2 Mapping of CBR2G5, CBR10G, CBR10G3 and CBR40G signals into OPUk 79 17.3
37、 Blank clause 83 17.4 Mapping of GFP frames into OPUk (k=0,1,2,3,4,flex) 83 17.5 Mapping of test signal into OPU 84 17.6 Mapping of a non-specific client bit stream into OPUk . 85 17.7 Mapping of other constant bit-rate signals with justification into OPUk . 86 17.8 Mapping a 1000BASE-X and FC-1200
38、signal via timing transparent transcoding into OPUk . 96 17.9 Mapping a supra-2.488 Gbit/s CBR signal into OPUflex using BMP . 98 17.10 Mapping of packet client signals into OPUk 101 17.11 Mapping of FlexE client signals into OPUflex using IMP . 101 17.12 Mapping of FlexE aware signals into OPUflex
39、102 17.13 Mapping a 64b/66b PCS coded signal into OPUflex using BMP and 2-bit alignment of 66b code words . 106 18 Blank clause 108 19 Mapping ODUj signals into the ODTU signal and the ODTU into the OPUk tributary slots 108 19.1 OPUk tributary slot definition 108 19.2 ODTU definition 117 19.3 Multip
40、lexing ODTU signals into the OPUk . 119 19.4 OPUk multiplex overhead and ODTU justification overhead . 127 19.5 Mapping ODUj into ODTUjk 138 vi Rec. ITU-T G.709/Y.1331 (2016)/Amd.1 (11/2016) Page 19.6 Mapping of ODUj into ODTUk.ts 146 20 Mapping ODUk signals into the ODTUCn signal and the ODTUCn int
41、o the OPUCn tributary slots. 150 20.1 OPUCn tributary slot definition . 150 20.2 ODTUCn definition 154 20.3 Multiplexing ODTUCn signals into the OPUCn 155 20.4 OPUCn multiplex overhead and ODTU justification overhead . 156 20.5 Mapping ODUk into ODTUCn.ts 160 Annex A Forward error correction using 1
42、6-byte interleaved RS(255,239) codecs 163 Annex B Adapting 64B/66B encoded clients via transcoding into 513B code blocks . 165 B.1 Transmission order . 165 B.2 Client frame recovery . 165 B.3 Transcoding from 66B blocks to 513B blocks . 165 B.4 Link fault signalling . 170 Annex C Adaptation of OTU3
43、and OTU4 over multichannel parallel interfaces 171 Annex D Generic mapping procedure principles 174 D.1 Basic principle 174 D.2 Applying GMP in OTN 177 D.3 Cm(t) encoding and decoding . 181 D.4 CnD(t) encoding and decoding 187 Annex E Adaptation of parallel 64B/66B encoded clients . 189 E.1 Introduc
44、tion 189 E.2 Clients signal format . 189 E.3 Client frame recovery . 189 E.4 Additions to Annex B transcoding for parallel 64B/66B clients 192 Annex F Improved robustness for mapping of 40GBASE-R into OPU3 using 1027B code blocks . 195 F.1 Introduction 195 F.2 513B code block framing and flag bit pr
45、otection . 195 F.3 66B block sequence check 196 Annex G Mapping ODU0 into a low latency OTU0 (OTU0LL) . 200 G.1 Introduction 200 G.2 Optical transport unit 0 low latency (OTU0LL) . 200 Annex H OTUCn sub rates (OTUCn-M) 203 H.1 Introduction 203 H.2 OTUCn-M frame format 203 Appendix I Range of stuff r
46、atios for asynchronous mappings of CBR2G5, CBR10G, and CBR40G clients with 20 ppm bit-rate tolerance into OPUk, and for asynchronous multiplexing of ODUj into ODUk (k j) 204 Rec. ITU-T G.709/Y.1331 (2016)/Amd.1 (11/2016) vii Page Appendix II Examples of functionally standardized OTU frame structures
47、 210 Appendix III Example of ODUk multiplexing . 213 Appendix IV Blank appendix . 215 Appendix V ODUk multiplex structure identifier (MSI) examples . 216 Appendix VI Parallel logic implementation of the CRC-9, CRC-8, CRC-5 and CRC-6 . 218 Appendix VII OTL4.10 structure 221 Appendix VIII CPRI into OD
48、U mapping . 222 Appendix IX Overview of CBR clients into OPU mapping types . 223 Appendix X Overview of ODUj into OPUk mapping types 225 Appendix XI Derivation of recommended ODUflex(GFP) bit-rates and examples of ODUflex(GFP) clock generation 227 XI.1 Introduction 227 XI.2 Tributary slot sizes . 22
49、7 XI.3 Example methods for ODUflex(GFP) clock generation 230 Appendix XII Terminology changes between ITU-T G.709 Edition 4 and Edition 5 232 Appendix XIII OTUCn sub rates (OTUCn-M) Applications . 234 XIII.1 Introduction 234 XIII.2 OTUCn-M frame format and rates . 234 XIII.3 OTUCn-M fault condition 235 Bibliography. 236 Rec. ITU-T G.709/Y.1331 (2016)/Amd.1 (11/2016) 1 Recommendation ITU-
