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.8121/Y.1381 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Amendment 1 (08/2017) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Packet over Transport aspects MPLS over Transport aspects SERIES Y:
2、GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS, NEXT-GENERATION NETWORKS, INTERNET OF THINGS AND SMART CITIES Internet protocol aspects Transport Characteristics of MPLS-TP equipment functional blocks Amendment 1 Recommendation ITU-T G.8121/Y.1381 (2016) Amendment 1 ITU-T G-SERIES RECO
3、MMENDATIONS TRANSMISSION SYSTEMS AND 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 METALLI
4、C LINES G.300G.399 GENERAL CHARACTERISTICS 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 DI
5、GITAL TERMINAL EQUIPMENTS G.700G.799 DIGITAL 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
6、.7999 PACKET OVER TRANSPORT ASPECTS G.8000G.8999 Ethernet over Transport aspects G.8000G.8099 MPLS over Transport aspects G.8100G.8199 Synchronization, quality and availability targets G.8200G.8299 Service Management G.8600G.8699 ACCESS NETWORKS G.9000G.9999 For further details, please refer to the
7、list of ITU-T Recommendations. Rec. ITU-T G.8121/Y.1381 (2016)/Amd.1 (08/2017) i Recommendation ITU-T G.8121/Y.1381 Characteristics of MPLS-TP equipment functional blocks Amendment Summary Recommendation ITU-T G.8121/Y.1381 specifies both the functional components and the methodology that should be
8、used in order to specify multi-protocol label switching transport profile (MPLS-TP) layer network functionality of network elements; it does not specify individual MPLS-TP network equipment as such. Corrigendum 1 removes irrelevant indexes in a few “OAM Tool“ MIs. Amendment 1 deletes the LCAS-capabl
9、e ODUk to MPLS-TP Adaptation function (clause 11.2.2) which is left as an empty clause. Figures 1-1 and 9-1 were also replaced. History Edition Recommendation Approval Study Group Unique ID* 1.0 ITU-T G.8121/Y.1381 2006-03-29 15 11.1002/1000/8785 1.1 ITU-T G.8121/Y.1381 (2006) Cor. 1 2006-12-14 15 1
10、1.1002/1000/9007 1.2 ITU-T G.8121/Y.1381 (2006) Amd. 1 2007-10-22 15 11.1002/1000/9178 2.0 ITU-T G.8121/Y.1381 2012-09-21 15 11.1002/1000/11517 2.1 ITU-T G.8121/Y.1381 (2012) Amd. 1 2012-12-22 15 11.1002/1000/11800 3.0 ITU-T G.8121/Y.1381 2013-11-06 15 11.1002/1000/12020 4.0 ITU-T G.8121/Y.1381 2016
11、-04-13 15 11.1002/1000/12804 4.1 ITU-T G.8121/Y.1381 (2016) Cor. 1 2016-11-13 15 11.1002/1000/13100 4.2 ITU-T G.8121/Y.1381 (2016) Amd. 1 2017-08-13 15 11.1002/1000/13317 Keywords Atomic functions, equipment functional blocks, multi-protocol label switching transport profile, MPLS-TP, MPLS-TP layer
12、network. * 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-en. ii Rec. ITU-T G.8121/Y.1381 (2016)/Amd.1 (08/2017) FOREWORD The International Tele
13、communication 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 permanent organ of ITU. ITU-T is responsible for studying technical, operating and t
14、ariff 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, establishes the topics for study by the ITU-T study groups which, in turn, produce Reco
15、mmendations 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 standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recomm
16、endation, 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 Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperabi
17、lity 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 equivalents are used to express requirements. The use of such words does not suggest that complian
18、ce 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 claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or
19、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 received notice of intellectual property, protected by patents, which may be required to impl
20、ement 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/ipr/. ITU 2017 All rights reserved. No part of this publication may be reproduced, by any m
21、eans whatsoever, without the prior written permission of ITU. Rec. ITU-T G.8121/Y.1381 (2016)/Amd.1 (08/2017) iii Table of Contents Page 1 Scope . 1 2 References . 2 3 Definitions 4 3.1 Terms defined elsewhere 4 3.2 Terms defined elsewhere 5 4 Abbreviations and acronyms 5 5 Conventions 8 6 Supervisi
22、on . 9 6.1 Defects 9 6.2 Consequent actions . 16 6.3 Defect correlations 16 6.4 Performance filters . 16 7 Information flow across reference points . 16 8 MPLS-TP processes 16 8.1 G-ACh process . 16 8.2 TC/Label processes 18 8.3 Queuing process . 20 8.4 MPLS-TP-specific GFP-F processes 21 8.5 Contro
23、l word (CW) processes 23 8.6 OAM related processes used by server adaptation functions . 24 8.7 OAM related processes used by adaptation functions 26 8.8 Proactive and on-demand OAM related processes . 32 8.9 Dataplane loopback processes 41 9 MPLS-TP layer functions . 43 9.1 Connection functions 45
24、9.2 Termination functions 54 9.3 Adaptation functions 64 9.4 MT diagnostic function 72 9.5 MPLS-TP MEP and MIP functions 83 10 MPLS-TP to Non-MPLS-TP client adaptation functions . 85 10.1 MPLS-TP to ETH adaptation function (MT/ETH_A) . 85 10.2 MPLS-TP to SCC and MCC adaptation functions . 91 11 Non-
25、MPLS-TP server to MPLS-TP adaptation functions 97 11.1 SDH to MPLS-TP adaptation function (S/MT_A) . 97 11.2 OTH to MPLS-TP adaptation function (O/MT_A) 117 11.3 PDH to MPLS-TP adaptation function (P/MT_A) . 136 iv Rec. ITU-T G.8121/Y.1381 (2016)/Amd.1 (08/2017) Page 11.4 Ethernet to MPLS-TP adaptat
26、ion function . 147 Appendix I Examples of processing of packets with expired TTL . 152 Appendix II Flow of PHB information through MEP and MIP . 156 Appendix III SDL descriptions . 158 Bibliography. 159 Rec. ITU-T G.8121/Y.1381 (2016)/Amd.1 (08/2017) 1 Recommendation ITU-T G.8121/Y.1381 Characterist
27、ics of MPLS-TP equipment functional blocks1 Amendment 1 Editorial note: This is a complete-text publication. Modifications introduced by this Amendment are shown in revision marks relative to Recommendation ITU-T G.8121/Y.1381 (2016) plus Cor. 1. 1 Scope This Recommendation describes both the functi
28、onal components and the methodology that should be used in order to describe multi-protocol label switching transport profile (MPLS-TP) layer network functionality of network elements; it does not describe individual MPLS-TP network equipment as such. This Recommendation provides a representation of
29、 the MPLS-TP technology using the methodologies that have been used for other transport technologies (e.g., synchronous digital hierarchy (SDH), optical transport network (OTN) and Ethernet).2 This Recommendation forms part of a suite of Recommendations covering the full functionality of network equ
30、ipment. These Recommendations are ITU-T G.705, ITU-T G.783, ITU-T G.798, ITU-T G.806 and ITU-T G.8021. This Recommendation also follows the principles defined in ITU-T G.805. These Recommendations specify a library of basic building blocks and a set of rules by which they may be combined in order to
31、 describe digital transmission equipment. The library comprises the functional building blocks needed to specify completely the generic functional structure of the MPLS-TP layer network. In order to be compliant with this Recommendation, equipment needs to be describable as an interconnection of a s
32、ubset of these functional blocks contained within this Recommendation. The interconnections of these blocks should obey the combination rules given. Not every atomic function defined in this Recommendation is required for every application. Different subsets of atomic functions may be assembled in d
33、ifferent ways according to the combination rules given in this Recommendation to provide a variety of different capabilities. Network operators and equipment suppliers may choose which functions must be implemented for each application. 1 Cisco Systems has expressed concerns that in the event of a d
34、ifference between this ITU-T Recommendation and any of the normatively referenced IETF RFCs, interoperability issues may arise. To prevent interoperability issues, the behaviour defined in the IETF RFCs must be maintained, and any such differences must be resolved in coordination with the IETF in a
35、timely manner. Orange has expressed concerns that in the event of a difference between this ITU-T Recommendation and any of the normatively referenced IETF RFCs, interoperability issues may arise. To prevent interoperability issues, the behaviour defined in the IETF RFCs must be maintained, and any
36、such differences must be resolved in coordination with the IETF in a timely manner. Verizon Communications has expressed concerns that in the event of a difference between this ITU-T Recommendation and the behavior defined in the normatively referenced IETF RFCs, interoperability issues may arise. T
37、here is no guidance in this ITU-T Recommendation that describes how to address differences in behaviour between the Recommendation and the normatively referenced IETF RFCs. Verizon Communications feels that any difference should be resolved in coordination with the IETF in a timely manner and until
38、the issue is resolved, the behavior defined in the IETF RFCs should be maintained. 2 This ITU-T Recommendation is intended to be aligned with the IETF MPLS RFCs normatively referenced by this Recommendation. 2 Rec. ITU-T G.8121/Y.1381 (2016)/Amd.1 (08/2017) Figure 1-1 presents the set of atomic func
39、tions associated with the traffic signal transport. The functions are based on the functional architecture as described in ITU-T G.8110.1. It is noted that this Recommendation only defines Ethernet for the client of MPLS-TP as multi-protocol label switching - transport profile / Ethernet MAC layer n
40、etwork (MT/ETH) adaptation function. Figure 1-1 MPLS-TP atomic functions 2 References The following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated we
41、re valid. All Recommendations and other references are subject to revision; users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendations and other references listed below. A list of the currently valid ITU-T Recommend
42、ations is regularly published. The reference to a document within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. ITU-T G.704 Recommendation ITU-T G.704 (1998), Synchronous frame structures used at 1544, 6312, 2048, 8448 and 44 736 kbit/s hierarchical
43、 levels. ITU-T G.705 Recommendation ITU-T G.705 (2000), Characteristics of plesiochronous digital hierarchy (PDH) equipment functional blocks. ITU-T G.707 Recommendation ITU-T G.707/Y.1322 (2007), Network node interface for the synchronous digital hierarchy (SDH). ITU-T G.709 Recommendation ITU-T G.
44、709/Y.1331 (2016), Interfaces for the optical transport network. ITU-T G.783 Recommendation ITU-T G.783 (2006), Characteristics of synchronous digital hierarchy (SDH) equipment functional blocks. Rec. ITU-T G.8121/Y.1381 (2016)/Amd.1 (08/2017) 3 ITU-T G.798 Recommendation ITU-T G.798 (2012), Charact
45、eristics of optical transport network hierarchy equipment functional blocks. ITU-T G.805 Recommendation ITU-T G.805 (2000), Generic functional architecture of transport networks. ITU-T G.806 Recommendation ITU-T G.806 (2012), Characteristics of transport equipment Description methodology and generic
46、 functionality. ITU-T G.832 Recommendation ITU-T G.832 (1998), Transport of SDH elements on PDHnetworks Frame and multiplexing structures. ITU-T G.7041 Recommendation ITU-T G.7041/Y.1303 (2016), Generic framing procedure. ITU-T G.7043 Recommendation ITU-T G.7043/Y.1343 (2004), Virtual concatenation
47、of plesiochronous digital hierarchy (PDH) signals. ITU-T G.7044 Recommendation ITU-T G.7044/Y.1347 (2011), Hitless adjustment of ODUflex(GFP). ITU-T G.7712 Recommendation ITU-T G.7712/Y.1703 (2010), Architecture and specification of data communication network. ITU-T G.8021 Recommendation ITU-T G.802
48、1/Y.1341 (2015), Characteristics of Ethernet transport network equipment functional blocks. ITU-T G.8040 Recommendation ITU-T G.8040/Y.1340 (2005), GFP frame mapping into Plesiochronous Digital Hierarchy (PDH). ITU-T G.8101 Recommendation ITU-T G.8101/Y.1355 (2015), Terms and definitions for MPLS tr
49、ansport profile. ITU-T G.8110.1 Recommendation ITU-T G.8110.1/Y.1370.1 (2011), Architecture of the Multi-Protocol Label Switching transport profile layer network. ITU-T G.8131 Recommendation ITU-T G.8131/Y.1382 (2014), Linear protection switching for MPLS transport profile. ITU-T G.8251 Recommendation ITU-T G.8251 (2010), The control of jitter and wander within the optical transport network (OTN). ITU-T Y.1415 Recommendation ITU-T Y.1415 (2005), Ethern
