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 4 (01/2015) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Digital terminal equipment General SERIES Y: GLOBAL INFORMATION INFRA
2、STRUCTURE, INTERNET PROTOCOL ASPECTS AND NEXT-GENERATION NETWORKS Internet protocol aspects Transport Interfaces for the optical transport network (OTN) Amendment 4 Recommendation ITU-T G.709/Y.1331 (2012) Amendment 4 ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND
3、 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 CHARACTERISTICS OF INTERNATIONAL CAR
4、RIER 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.799 General G.700G.709 Coding
5、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 characteristics of transcoder and digi
6、tal 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 DIGITAL NETWORKS G.800G.899 DIGITA
7、L 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.8000G.8999 ACCESS NETWORKS G.9000
8、G.9999 For further details, please refer to the list of ITU-T Recommendations. Rec. ITU-T G.709/Y.1331 (2012)/Amd.4 (01/2015) i Recommendation ITU-T G.709/Y.1331 Interfaces for the optical transport network (OTN) Amendment 4 Summary Amendment 4 to Recommendation ITU-T G.709/Y.1331 (2012) contains ex
9、tensions related to the: addition of the OTSn OTN synchronization messaging channel (OSMC) overhead; addition of the OTUk OTN synchronization messaging channel (OSMC) overhead; modification of the OCh overhead transport over OTM-1 multi-vendor IaDI specification to align with the specifications in R
10、ecommendation ITU-T G.7712; addition of optional FEC processing in the FC-1600 client signal. 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.1
11、331 2003-03-16 15 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
12、/1000/9646 2.5 ITU-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 (
13、2009) Amd. 2 2011-04-13 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
14、/1000/11982 4.4 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 _ * To access the Recommendation, type the URL http:/handle.itu.int/ in the ad
15、dress 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.709/Y.1331 (2012)/Amd.4 (01/2015) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of tel
16、ecommunications, 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 on them with a view to standardizing telec
17、ommunications 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 ITU-T Recommendations is covered by the p
18、rocedure 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 used for conciseness to indicate both a t
19、elecommunication 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 the Recommendation is achieved when all o
20、f 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 of any party. INTELLECTUAL PROPERTY RIGHT
21、SITU 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 Property Rights, whether asserted by ITU m
22、embers 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, implementers are cautioned that this may not
23、 represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2015 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T G.709/Y
24、.1331 (2012)/Amd.4 (01/2015) iii Table of Contents Page 1) Introduction . 1 2) Additions. 1 2.1) Clause 7 1 2.2) Clause 15, Figure 15-1 . 1 2.3) Clause 15, Figure 15-2 . 1 2.4) Clause 15.3 . 2 2.5) Clause 15.5.4 2 2.6) Clause 15.7.1 3 2.7) Clause 15.7.2.3 . 3 2.8) Clause 15.7.2.4 . 3 2.9) Clause 17.
25、9.2 4 Rec. ITU-T G.709/Y.1331 (2012)/Amd.4 (01/2015) 1 Recommendation ITU-T G.709/Y.1331 Interfaces for the optical transport network (OTN) Amendment 4 1) Introduction This amendment contains extensions to the fourth version (02/2012) of Recommendation ITU-T G.709/Y.1331; these relate to the: additi
26、on of the OTSn OTN synchronization messaging channel (OSMC) overhead (clauses 7, 15, 15.3, 15.3.5); addition of the OTUk OTN synchronization messaging channel (OSMC) overhead (clauses 15, 15.7.1, 15.7.2.3, 15.7.2.4); modification of the OCh overhead transport over OTM-1 multi-vendor IaDI specificati
27、on to align with the specifications in ITU-T G.7712 (clause 15.5.4); addition of optional FEC processing in the FC-1600 client signal (clause 17.9.2). 2) Additions 2.1) Clause 7 Modify the text in this clause as follows: The OTS (with optional OSMC), OMS, OCh and COMMS overhead is inserted into the
28、OOS using mapping and multiplexing techniques which are outside the scope of this Recommendation. 2.2) Clause 15, Figure 15-1 Replace Figure 15-1 with the following figure that includes the OTSn OSMC overhead: Figure 15-1 OTSn, OMSn and OCh overhead as logical elements within the OOS 2.3) Clause 15,
29、 Figure 15-2 Replace Figure 15-2 with the following figure that includes the OTUk OSMC overhead in row 1, column 13 and modify the figure legend as shown: 2 Rec. ITU-T G.709/Y.1331 (2012)/Amd.4 (01/2015) Figure 15-2 OTUk frame structure, frame alignment and OTUk overhead 2.4) Clause 15.3 Extend the
30、list of OTSn overhead in clause 15.3 with the OTSn OSMC overhead and add a new clause 15.3.5 OTSn OSMC to clause 15.3 as presented hereafter: 15.3 OTS OH description The following OTM-n OTSn overhead is defined: OTSn-TTI OTSn-BDI-P OTSn-BDI-O OTSn-PMI OTSn-OSMC. 15.3.5 OTSn OTN synchronization messa
31、ge channel (OSMC) For synchronization purposes, the OTSn OSMC signal is defined as an OTN synchronization message channel to transport SSM and PTP messages. NOTE 1 Support of OTSn OSMC in an OTM-n interface is optional. NOTE 2 Old equipment may not be able to support OTSn OSMC via their OTM-n interf
32、aces. Rec. ITU-T G.709/Y.1331 (2012)/Amd.4 (01/2015) 3 2.5) Clause 15.5.4 Modify the text in clause 15.5.4 as follows: Figure 15-5bis illustrates the information and representation to be used when the OCh overhead is to be transferred across a multi-vendor IaDI. This information consists of OCh over
33、head primitives and of additional information including an OH type field, a trail trace identifier field to check for misconnections over the OCN and a field indicating the nominal central frequency of the associated OCh payload. In the case of single-vendor IaDI, the coding and method of OCh overhe
34、ad information transfer is vendor specific. For multi-vendor IaDI, the OCh overhead is transferred over the overhead communication network (OCN) as described in ITU-T G.7712. NOTE A multi-vendor IaDI which transfers OCh overhead over an OCN cannot provide fate-sharing of the OCh overhead with the OC
35、h payload across this interface. Each OCh overhead primitive is represented by a bit that is set to one if the respective condition is present, and will be set to zero when it is not. The OCh FDI-P, FDI-O and OCI overhead primitives are communicated over the OCN. The specification of the encapsulati
36、on, identification and transmission of this information is outside the scope of this Recommendation and specified in ITU-T G.7712. This information must be communicated with the peers such that the OCh overhead primitives come into sync within one second in the absence of changes to OCh FDI-P, FDI-O
37、 or OCI. In the event of changes to any OCh overhead primitive, the update must be sent within 10 ms of the change and with a mechanism to guarantee receipt in the event of packet loss. Size Contents 2 octets OH type, 0x0001=OCh overhead 64 octets Trail trace identifier (TTI): 16 octets SAPI 16 octe
38、ts DAPI 32 octets operator specific 4 octets Nominal central frequency (NCF) Encoded as a “DWDM Wavelength Label” per Section 3.2 of b-IETF RFC 6205 1 octet OAM bits The OAM bits are represented as follows: 1 2 3 4 5 6 7 8 FDI-P FDI-O OCI Reserved Figure 15-5bis OCh overhead information elements to
39、be used for multi-vendor 15.5.4.1 Trail trace identifier (TTI) The TTI is defined to transport a 64-byte TTI as specified in clause 15.2 over a multi-vendor IaDI to ensure there are no misconnections across the OCN. 15.5.4.2 Nominal central frequency (NCF) The NCF encodes the nominal central frequen
40、cy of the intended OCh payload. This is sent explicitly across a multi-vendor IaDI to ensure there are no misconnections across the OCN. The coding for this information for a multi-vendor IaDI is specified in clause 15.5.4. 4 Rec. ITU-T G.709/Y.1331 (2012)/Amd.4 (01/2015) 2.6) Clause 15.7.1 Replace
41、Figure 15-9 with the following figure that includes OTUk OSMC overhead in row 1, column 13: Figure 15-9 OTUk overhead 2.7) Clause 15.7.2.3 Modify the text in clause 15.7.2.3 as follows: Two One bytes of an the OTUk overhead are is reserved for future international standardization. Theise bytes areis
42、 located in row 1, columns 13 and 14. Theise bytes areis set to all-0s. 2.8) Clause 15.7.2.4 Add the following new clause, clause 15.7.2.4 OTUk OTN synchronization message channel (OSMC), after clause 15.7.2.3: 15.7.2.4 OTUk OTN synchronization message channel (OSMC) For synchronization purposes, on
43、e byte is defined in the OTUk overhead as an OTN synchronization message channel to transport SSM and PTP messages within OTM-0 and OTM-nr inter-domain interfaces. The OSMC bandwidth is listed in Table 15-1bis. NOTE 1 OTUk OSMC is not defined for OTM-n and OTM-1 intra-domain interfaces. NOTE 2 Suppo
44、rt of OTUk OSMC in an OTM-0 and OTM-nr inter-domain interface is optional. NOTE 3 Old equipment may not be able to support OTUk OSMC via their OTM-0 and OTM-nr interfaces. NOTE 4 OTM-0 and OTM-nr single-vendor intra-domain interfaces may support an OSMC function. The encapsulation of the messages an
45、d overhead location are then vendor specific. Table 15-1bis OSMC bandwidth OTUk OSMC bandwidth (kbit/s) OTU1 163.361 OTU2 656.203 OTU3 2635.932 OTU4 6851.101 The SSM and PTP messages within an OTM-0 and OTM-nr inter-domain interface are encapsulated into GFP-F frames as specified in ITU-T G.7041. GF
46、P frames arrive as a continuous bit stream with a capacity that is identical to the OSMC overhead bandwidth, due to the insertion of idle frames at the GFP encapsulation stage. The GFP frame stream is not scrambled during encapsulation. NOTE 5 There is no rate adaptation or scrambling required at th
47、e mapping stage; this is performed by the GFP encapsulation process. The mapping of generic framing procedure (GFP) frames is performed by aligning the byte structure of every GFP frame with the byte of the OSMC overhead field. Since the GFP frames are of variable length and longer than one byte, a
48、frame crosses the OTUk (k=1,2,3,4) frame boundary. Rec. ITU-T G.709/Y.1331 (2012)/Amd.4 (01/2015) 5 2.9) Clause 17.9.2 Modify the text in this clause as follows: 17.9.2 FC-1600 The characteristic information of the mapped FC-1600 client signal consists of a sequence of 64B/66B encoded blocks with a
49、nominal bit-rate of 14 025 000 kbit/s, 100 ppm. In case the FC-1600 interface at the mapper has FEC enabled, the mapper must recover the FEC code word synchronization, extract the FEC parity bits, perform error correction and transdecode the 64B/65B blocks to 64B/66B blocks as specified in b-INCITS 470. In case the FC-1600 interface at the demapper has FEC enabled, the demapper must recover 66B block lock from the demapped CBR signal, transcode the 64B/66B block
