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.8131/Y.1382 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Amendment 2 (11/2016) 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 AND NEXT-GENERATION NETWORKS, INTERNET OF THINGS AND SMART CITIES Internet protocol aspects Transport Linear protection switching for MPLS transport profile Amendment 2 Recommendation ITU-T G.8131/Y.1382 (2014) Amendment 2 ITU-T G-SERIES R
3、ECOMMENDATIONS 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 META
4、LLIC 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
5、 DIGITAL 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.70
6、00G.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 t
7、he list of ITU-T Recommendations. Rec. ITU-T G.8131/Y.1382 (2014)/Amd.2 (11/2016) i Recommendation ITU-T G.8131/Y.1382 Linear protection switching for MPLS transport profile Amendment 2 Summary Recommendation ITU-T G.8131/Y.1382 provides architecture and mechanisms for subnetwork connection (SNC) pr
8、otection switching for MPLS transport profile (MPLS-TP) networks. It describes the SNC protection architectures type, the uni- and bidirectional switching types and the revertive/non-revertive operation types. It defines an automatic protection coordination protocol used to coordinate both ends of t
9、he protected domain. Amendment 1 provided the format of APC specific information, and descriptions about management (MI) signals and trail protection architecture. Amendment 2 to Recommendation ITU-T G.8131/Y.1382 (2014) provides: Support for pseudowire (PW) protection. Modifications to the referenc
10、es of terms related to new Recommendation ITU-T G.808 History Edition Recommendation Approval Study Group Unique ID* 1.0 ITU-T G.8131/Y.1382 2007-02-06 15 11.1002/1000/9008 1.1 ITU-T G.8131/Y.1382 (2007) Amd. 1 2007-09-22 15 11.1002/1000/9179 2.0 ITU-T G.8131/Y.1382 2014-07-07 15 11.1002/1000/12188
11、2.1 ITU-T G.8131/Y.1382 (2014) Amd. 1 2016-04-13 15 11.1002/1000/12807 2.2 ITU-T G.8131/Y.1382 (2014) Amd. 2 2016-11-13 15 11.1002/1000/13103 Keywords APC, APS, PSC, bridge, selector, SNC protection, MPLS-TP. _ * To access the Recommendation, type the URL http:/handle.itu.int/ in the address field o
12、f 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.8131/Y.1382 (2014)/Amd.2 (11/2016) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunicati
13、ons, 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 telecommunication
14、s 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 procedure lai
15、d 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 telecommunica
16、tion 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 of these mand
17、atory 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 RIGHTSITU draws a
18、ttention 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 members or ot
19、hers 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 represent t
20、he 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 written permission of ITU. Rec. ITU-T G.8131/Y.1382 (2014
21、)/Amd.2 (11/2016) iii Table of Contents Page 1 Scope . 1 2 References . 1 3 Definitions 2 3.1 Terms defined elsewhere 2 3.2 Terms defined in this Recommendation . 3 4 Abbreviations and acronyms 3 5 Conventions 4 6 Protection architecture and characteristics . 5 6.1 MPLS-TP protection architecture .
22、5 6.2 Switching types 5 6.3 Operation types . 6 6.4 Protection switching trigger mechanism 6 6.5 Provisioning mismatches 7 7 Protection group commands and state 7 7.1 End-to-end commands 7 7.2 Local commands . 8 7.3 States . 8 8 Automatic protection coordination protocol . 9 8.1 Automatic protection
23、 coordination specific information structure 9 8.2 Priorities of local and remote requests . 12 8.3 APC initiation criteria . 13 8.4 APC protocol type 13 8.5 Transmission and acceptance of APC messages 14 8.6 1-phase APC protocol . 14 8.7 Equal priority requests 16 8.8 Control of bridge 17 8.9 Contr
24、ol of selector 17 8.10 Acceptance and retention of local requests 17 8.11 Hold-off timer . 18 8.12 Wait-to-restore timer 18 8.13 Exercise operation 18 8.14 Signal degrade processing 18 8.15 Failure of protocol defects 19 9 Application architectures 19 9.1 Unidirectional 1+1 SNC/S protection switchin
25、g 19 9.2 Bidirectional 1+1 SNC/S protection switching 21 iv Rec. ITU-T G.8131/Y.1382 (2014)/Amd.2 (11/2016) Page 9.3 Bidirectional 1:1 SNC/S protection switching . 22 9.4 Relationship with ITU-T G.8131 (2007) 25 9.5 Pseudowire protection 25 10 Security aspects 26 Annex A State transition tables of p
26、rotection switching. 27 Appendix I Operation example of MPLS-TP linear protection protocol 28 Appendix II Format of APC specific information 29 Rec. ITU-T G.8131/Y.1382 (2014)/Amd.2 (11/2016) 1 Recommendation ITU-T G.8131/Y.1382 Linear protection switching for MPLS transport profile Amendment 2 Edit
27、orial note: This is a complete-text publication. Modifications introduced by this amendment are shown in revision marks relative to Recommendation ITU-T G.8131/Y.1382 (2014) plus its Amendment 1 (2016). 1 Scope This Recommendation provides architecture and mechanisms for linear protection switching
28、for MPLS transport profile (MPLS-TP) networks. The automatic protection coordination protocol, and 1+1 and 1:1 protection architecture are defined in this Recommendation. Other protection architecture types are for further study. This Recommendation describes the protection switching functionality f
29、or point-to-point connections using the automatic protection switching (APS) mode defined in IETF RFC 7271. This Recommendation provides a representation of the MPLS-TP technology using the methodologies that have been used for other transport technologies (e.g., synchronous digital hierarchy (SDH),
30、 optical transport network (OTN) and Ethernet).1 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 were valid. All Recommenda
31、tions 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 Recommendations is regularly publ
32、ished. 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.780 Recommendation ITU-T G.780/Y.1351 (2010), Terms and definitions for synchronous digital hierarchy (SDH) networks. ITU-T G.805 Recommendation ITU-T G.
33、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 functionality. ITU-T G.808 Recommendation ITU-T G.808 (2016), Terms and definitions for network protection and
34、restoration. ITU-T G.808.1 Recommendation ITU-T G.808.1 (2014), Generic protection switching Linear trail and subnetwork protection. ITU-T G.870 Recommendation ITU-T G.870/Y.1352 (2012), Terms and definitions for optical transport networks. _ 1 This ITU-T Recommendation is intended to be aligned wit
35、h the IETF MPLS RFCs normatively referenced by this Recommendation. 2 Rec. ITU-T G.8131/Y.1382 (2014)/Amd.2 (11/2016) ITU-T G.8031 Recommendation ITU-T G.8031/Y.1342 (2011), Ethernet linear protection switching. ITU-T G.8110.1 Recommendation ITU-T G.8110.1/Y.1370.1 (2011), Architecture of the Multi-
36、Protocol Label Switching transport profile layer network. ITU-T G.8121 Recommendation ITU-T G.8121/Y.1381 (2013), Characteristics of MPLS-TP equipment functional blocks. IETF RFC 5586 IETF RFC 5586 (2009), MPLS Generic Associated Channel IETF RFC 6378 IETF RFC 6378 (2011), MPLS Transport Profile (MP
37、LS-TP) Linear Protection. IETF RFC 7271 IETF RFC 7271 (2014), MPLS Transport Profile (MPLS-TP) Linear Protection to Match the Operational Expectations of Synchronous Digital Hierarchy, Optical Transport Network, and Ethernet Transport Network Operators. IETF RFC 7771-A IETF RFC 7771 (2016), Switchin
38、g Provider Edge (S-PE) Protection for MPLS and MPLS Transport Profile (MPLS-TP) Static Multi-Segment Pseudowires; Appendix A Optional Linear Protection Approach. 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses the following terms defined elsewhere: 3.1.1 1+1 protection architectur
39、e ITU-T G.870 3.1.2 1:n protection architecture ITU-T G.870 3.1.3 1-phase ITU-T G.870 3.1.4 2-phase ITU-T G.870 3.1.5 3-phase ITU-T G.870 3.1.6 active transport entity ITU-T G.870 3.1.7 APS protocol ITU-T G.870 3.1.8 architecture ITU-T G.870 3.1.9 bidirectional protection switching ITU-T G.780 3.1.1
40、0 bridge ITU-T G.870 3.1.11 defect ITU-T G.806 3.1.12 failure ITU-T G.806 3.1.13 forced switch ITU-T G.870 3.1.14 hold-off time ITU-T G.870 3.1.15 manual switch ITU-T G.870 3.1.16 non-revertive (protection) operation ITU-T G.870 3.1.17 normal traffic signal ITU-T G.870 3.1.18 permanent bridge ITU-T
41、G.870 3.1.19 protected domain ITU-T G.870 Rec. ITU-T G.8131/Y.1382 (2014)/Amd.2 (11/2016) 3 3.1.20 protection ITU-T G.870 3.1.21 protection group ITU-T G.870 3.1.22 protection transport entity ITU-T G.870 3.1.23 revertive (protection) operation ITU-T G.870 3.1.24 selector ITU-T G.870 3.1.25 selector
42、 bridge ITU-T G.870 3.1.26 signal ITU-T G.870 3.1.27 signal degrade (SD) ITU-T G.806 3.1.28 signal fail (SF) ITU-T G.806 3.1.29 standby transport entity ITU-T G.870 3.1.30 subnetwork connection protection ITU-T G.870 3.1.31 switch ITU-T G.870 3.1.32 traffic signal ITU-T G.870 3.1.33 trail ITU-T G.80
43、5 3.1.34 trail protection ITU-T G.870 3.1.35 transport entities ITU-T G.870 3.1.36 unidirectional protection switching ITU-T G.780 3.1.37 wait-to-restore time ITU-T G.870 3.1.38 working transport entity ITU-T G.870 3.1.1 1+1 protection architecture ITU-T G.808 3.1.2 1:n protection architecture ITU-T
44、 G.808 3.1.3 1-phase ITU-T G.808 3.1.4 2-phase ITU-T G.808 3.1.5 3-phase ITU-T G.808 3.1.6 active transport entity ITU-T G.808 3.1.6 APS protocol ITU-T G.808 3.1.7 bidirectional protection switching ITU-T G.780 3.1.8 bridge ITU-T G.808 3.1.9 defect ITU-T G.806 3.1.10 failure ITU-T G.806 3.1.11 force
45、d switch ITU-T G.808 3.1.12 hold-off time ITU-T G.880 3.1.13 manual switch ITU-T G.808 3.1.14 non-revertive (protection) operation ITU-T G.808 3.1.15 normal traffic signal ITU-T G.808 3.1.16 permanent bridge ITU-T G.808 3.1.17 protected domain ITU-T G.808 4 Rec. ITU-T G.8131/Y.1382 (2014)/Amd.2 (11/
46、2016) 3.1.18 protection ITU-T G.808 3.1.19 protection group ITU-T G.808 3.1.20 protection transport entity ITU-T G.808 3.1.21 revertive (protection) operation ITU-T G.808 3.1.22 selector ITU-T G.808 3.1.23 selector bridge ITU-T G.808 3.1.24 signal degrade (SD) ITU-T G.806 3.1.25 signal fail (SF) ITU
47、-T G.806 3.1.26 standby transport entity ITU-T G.808 3.1.27 subnetwork connection protection ITU-T G.808 3.1.28 switch ITU-T G.808 3.1.29 trail ITU-T G.805 3.1.30 trail protection ITU-T G.807 3.1.31 transport entity ITU-T G.805 3.1.32 unidirectional protection switching ITU-T G.780 3.1.33 wait-to-re
48、store time ITU-T G.808 3.1.34 working transport entity ITU-T G.808 3.2 Terms defined in this Recommendation This Recommendation defines the following term: 3.2.1 PSC protocol: A means to coordinate the two ends of the protected domain via the exchange of a single message as defined in IETF RFC 6378.
49、 4 Abbreviations and acronyms This Recommendation uses the following abbreviations and acronyms: ACH Associated Channel Header APC Automatic Protection Coordination APS Automatic Protection Switching dFOP Failure of Protocol defect DNR Do-not-Revert DPath Data Path EXER Exercise FPath Fault Path FS Force
