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.8032/Y.1344 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Corrigendum 1 (08/2017) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Packet over Transport aspects Ethernet over Transport aspects SERI
2、ES Y: GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS, NEXT-GENERATION NETWORKS, INTERNET OF THINGS AND SMART CITIES Internet protocol aspects Transport Ethernet ring protection switching Corrigendum 1 Recommendation ITU-T G.8032/Y.1344 (2015) Corrigendum 1 ITU-T G-SERIES RECOMMENDATION
3、S 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 METALLIC LINES G.
4、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 DIGITAL TERM
5、INAL 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.7999 PACK
6、ET 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 list of IT
7、U-T Recommendations. Rec. ITU-T G.8032/Y.1344 (2015)/Cor.1 (08/2017) i Recommendation ITU-T G.8032/Y.1344 Ethernet ring protection switching Corrigendum 1 Summary Recommendation ITU-T G.8032/Y.1344 defines the automatic protection switching (APS) protocol and protection switching mechanisms for Ethe
8、rnet layer network (ETH) ring topologies. Included are details pertaining to Ethernet ring protection characteristics, architectures and the ring APS (R-APS) protocol. Amendment 1 provides support for management information indicating the node state of an Ethernet ring node and the port states of an
9、 Ethernet ring nodes ports. It also updates references to Recommendation ITU-T G.870/Y.1352 with references to Recommendation ITU-T G.808. Corrigendum 1 clarifies clause 10.1.10, Flush logic. History Edition Recommendation Approval Study Group Unique ID* 1.0 ITU-T G.8032/Y.1344 2008-06-22 15 11.1002
10、/1000/9415 1.1 ITU-T G.8032/Y.1344 (2008) Amd. 1 2009-04-22 15 11.1002/1000/9678 2.0 ITU-T G.8032/Y.1344 2010-03-09 15 11.1002/1000/10661 2.1 ITU-T G.8032/Y.1344 (2010) Amd. 1 2010-06-11 15 11.1002/1000/10934 2.2 ITU-T G.8032/Y.1344 (2010) Cor. 1 2010-10-07 15 11.1002/1000/10902 2.3 ITU-T G.8032/Y.1
11、344 (2010) Amd. 2 2011-02-25 15 11.1002/1000/11328 3.0 ITU-T G.8032/Y.1344 2012-02-13 15 11.1002/1000/11514 3.1 ITU-T G.8032/Y.1344 (2012) Amd. 1 2013-07-12 15 11.1002/1000/12025 4.0 ITU-T G.8032/Y.1344 2015-08-13 15 11.1002/1000/12550 4.1 ITU-T G.8032/Y.1344 (2015) Amd. 1 2016-11-13 15 11.1002/1000
12、/13096 4.2 ITU-T G.8032/Y.1344 (2015) Cor. 1 2017-08-13 15 11.1002/1000/13313 _ * 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
13、-T G.8032/Y.1344 (2015)/Cor.1 (08/2017) 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 permanent org
14、an 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, establishes the
15、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 standards are
16、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 Recommendatio
17、n 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 equivalents are used
18、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 claimed Intellectua
19、l 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 received notice
20、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/ipr/. ITU 2017
21、 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.8032/Y.1344 (2015)/Cor.1 (08/2017) iii Table of Contents Page 1 Scope . 1 2 References . 1 3 Definitions 2 3.1 Terms defined elsewhere 2 3.2 Terms d
22、efined in this Recommendation . 3 4 Abbreviations and acronyms 3 5 Conventions 4 5.1 Representation of octets . 4 6 Introduction . 5 7 Ring protection characteristics . 5 7.1 Monitoring methods and conditions . 5 7.2 Ethernet traffic and bandwidth consideration . 6 7.3 Ethernet ring protection switc
23、hing performance 6 8 Ring protection conditions and commands. 6 9 Ring protection architectures 7 9.1 Revertive and non-revertive switching . 7 9.2 Protection switching triggers 7 9.3 Protection switching models on a single Ethernet ring 7 9.4 Traffic channel blocking . 11 9.5 R-APS channel blocking
24、 11 9.6 Filtering database flush . 12 9.7 Ethernet ring protection switching models for interconnection . 12 10 Protection control protocol . 21 10.1 Principles of operations 21 10.2 Protection switching behaviour 38 10.3 R-APS format . 43 10.4 Failure of protocol defect . 45 Appendix I Ring protect
25、ion network objectives . 46 Appendix II Ethernet ring network objectives 48 Appendix III Ring protection scenarios 50 Appendix IV Considerations for different timers . 59 IV.1 State machine use of timers 59 IV.2 Guard timer use to block outdated R-APS messages . 59 Appendix V 61 Appendix VI . 62 App
26、endix VII . 63 iv Rec. ITU-T G.8032/Y.1344 (2015)/Cor.1 (08/2017) Page Appendix VIII Flush optimization 64 VIII.1 Flushing FDB consideration . 64 VIII.2 Scenarios of unnecessary FDB flushing . 64 VIII.3 Example of FDB flush optimization . 64 VIII.4 Additional definition of the ERP control process mo
27、del and state machine 65 VIII.5 DNF status 69 Appendix IX . 70 Appendix X 71 Appendix XI . 72 Bibliography. 73 Rec. ITU-T G.8032/Y.1344 (2015)/Cor.1 (08/2017) 1 Recommendation ITU-T G.8032/Y.1344 Ethernet ring protection switching Corrigendum 1 Editorial note: This is a complete-text publication. Mo
28、difications introduced by this corrigendum are shown in revision marks relative to Recommendation ITU-T G.8032/Y.1344 (2015) plus Amendment 1. 1 Scope This Recommendation defines the automatic protection switching (APS) protocol and protection switching mechanisms for Ethernet layer network (ETH) ri
29、ng topologies. The protection protocol defined in this Recommendation enables protected point-to-point, point-to-multipoint and multipoint-to-multipoint connectivity within a ring or interconnected rings, called “multi-ring/ladder network“ topology. The ETH ring maps to the physical layer ring struc
30、ture. Protection schemes for the other layers, including the Ethernet physical layer network (ETY), are out of the scope of this Recommendation. 2 References The following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute provisions of th
31、is Recommendation. At the time of publication, the editions indicated were 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 othe
32、r references listed below. A list of the currently valid ITU-T Recommendations 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.805 Recommendation ITU-T G.805 (2000), Generic functional
33、 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 restoration. ITU-T G.808.1 Rec
34、ommendation ITU-T G.808.1 (2014), Generic protection switching Linear trail and subnetwork protection. ITU-T G.809 Recommendation ITU-T G.809 (2003), Functional architecture of connectionless layer networks. ITU-T G.8001 Recommendation ITU-T G.8001/Y.1354 (2016), Terms and definitions for Ethernet f
35、rames over transport. ITU-T G.8010 Recommendation ITU-T G.8010/Y.1306 (2004), Architecture of Ethernet layer networks. ITU-T G.8013 Recommendation ITU-T G.8013/Y.1731 (2015), Operation, administration and management (OAM) functions and mechanisms for Ethernet based networks. 2 Rec. ITU-T G.8032/Y.13
36、44 (2015)/Cor.1 (08/2017) ITU-T G.8021 Recommendation ITU-T G.8021/Y.1341 (2016), Characteristics of Ethernet transport network equipment functional blocks. IEEE 802.1Q IEEE Std 802.1Q (2014), IEEE standard for local and metropolitan area networks: Media access control (MAC) bridges and virtual brid
37、ged local area networks. 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses the following terms defined elsewhere: 3.1 Terms defined elsewhere This Recommendation uses the following terms defined elsewhere: 3.1.1 adaptation: ITU-T G.809 3.1.2 adapted information: ITU-T G.805 3.1.3 ch
38、aracteristic information: ITU-T G.805 3.1.4 defect: ITU-T G.806 3.1.5 ERP instance: ITU-T G.8001 3.1.6 Ethernet ring node: ITU-T G.8001 3.1.7 Ethernet ring: ITU-T G.8001 3.1.8 failure: ITU-T G.806 3.1.9 flow: ITU-T G.809 3.1.10 hold-off time: ITU-T G.808 3.1.11 interconnection node: ITU-T G.8001 3.1
39、.12 layer network: ITU-T G.809 3.1.13 link: ITU-T G.805 3.1.14 maintenance entity (ME): ITU-T G.8001 3.1.15 maintenance entity group (MEG): ITU-T G.8001 3.1.16 major ring: ITU-T G.8001 3.1.17 MEG end point (MEP): ITU-T G.8001 3.1.18 network: ITU-T G.809 3.1.19 non-revertive (protection) operation: I
40、TU-T G.808 3.1.20 port: ITU-T G.809 3.1.21 protected domain: ITU-T G.808 3.1.22 protection transport entity: ITU-T G.808 3.1.23 protection: ITU-T G.808 3.1.24 R-APS virtual channel: ITU-T G.8001 3.1.25 revertive (protection) operation: ITU-T G.808 3.1.26 ring MEL: ITU-T G.8001 3.1.27 ring protection
41、 link (RPL): ITU-T G.8001 3.1.28 RPL neighbour node: ITU-T G.8001 3.1.29 RPL owner node: ITU-T G.8001 3.1.30 server signal fail (SSF): ITU-T G.806 3.1.31 signal degrade (SD): ITU-T G.806 Rec. ITU-T G.8032/Y.1344 (2015)/Cor.1 (08/2017) 3 3.1.32 signal fail (SF): ITU-T G.806 3.1.33 signal: ITU-T G.808
42、 3.1.34 sub-ring link: ITU-T G.8001 3.1.35 sub-ring: ITU-T G.8001 3.1.36 switch: ITU-T G.808 3.1.37 switching time: ITU-T G.808 3.1.38 tandem connection: ITU-T G.805 3.1.39 trail signal fail (TSF): ITU-T G.806 3.1.40 trail: ITU-T G.805 3.1.41 transfer time (Tt): ITU-T G.808.1 3.1.42 transport entity
43、: ITU-T G.809 3.1.43 transport: ITU-T G.809 3.1.44 wait to block timer: ITU-T G.8001 3.1.45 wait-to-restore time: ITU-T G.808 3.1.46 working transport entity: ITU-T G.808 3.2 Terms defined in this Recommendation None. 4 Abbreviations and acronyms This Recommendation uses the following abbreviations
44、and acronyms: AI Adapted Information APS Automatic Protection Switching BPR Blocked Port Reference CCM Continuity Check Message CI Characteristic Information DNF Do Not Flush E-LAN Ethernet LAN EPL Ethernet Private Line ERP Ethernet Ring Protection ETH Ethernet layer network ETHDi Ethernet MAC layer
45、 network Diagnostic function within MIP ETY Ethernet physical layer network EVPL Ethernet Virtual Private Line FDB Filtering Database FF Flow Forwarding FOP-PM Failure Of Protocol Provisioning Mismatch FOP-TO Failure Of Protocol Time Out FP Flow Point FS Forced Switch 4 Rec. ITU-T G.8032/Y.1344 (201
46、5)/Cor.1 (08/2017) GFP Generic Framing Procedure ID Identification MAC Media Access Control MEG Maintenance Entity Group MEL Maintenance Entity group Level MEP Maintenance entity group End Point MI Management Information MPLS Multiprotocol Label Switching MS Manual Switch NR No Request OAM Operation
47、, Administration and Maintenance OUI Organizationally Unique Identifier PDU Protocol Data Unit R-APS Ring APS RB RPL Blocked RPL Ring Protection Link SD Signal Degrade SDH VC Synchronous Digital Hierarchy Virtual Circuit SF Signal Fail SSF Server Signal Fail STP Spanning Tree Protocol TCM Tandem Con
48、nection Monitoring TLV Type, Length and Value Tx Transmit VID VLAN Identifier VLAN Virtual Local Area Network VPLS Virtual Private Local Area Network Service WTB Wait To Block WTR Wait To Restore 5 Conventions 5.1 Representation of octets Octets are represented as defined in ITU-T G.8013. When conse
49、cutive octets are used to represent a binary number, the lowest octet number has the most significant value. The bits in an octet are numbered from 1 to 8, where 1 is the least significant bit and 8 is the most significant bit. Rec. ITU-T G.8032/Y.1344 (2015)/Cor.1 (08/2017) 5 6 Introduction This Recommendation specifies protection switching mechanisms and a protocol for Ethernet layer netw
