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.8021/Y.1341 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (04/2015) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Packet over Transport aspects Ethernet over Transport aspects SERIES Y: GLOBAL I
2、NFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS AND NEXT-GENERATION NETWORKS Internet protocol aspects Transport Characteristics of Ethernet transport network equipment functional blocks Recommendation ITU-T G.8021/Y.1341 ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SY
3、STEMS 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 CHARACTERISTICS OF INTERNAT
4、IONAL 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.799 DIGITAL NETWORKS
5、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.8000G.8999 Ether
6、net 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 ITU-T Recommendations. Rec. ITU-T G.8021/Y.134
7、1 (04/2015) i Recommendation ITU-T G.8021/Y.1341 Characteristics of Ethernet transport network equipment functional blocks Summary Recommendation ITU-T G.8021/Y.1341 specifies both the functional components and the methodology that should be used in order to specify the Ethernet transport network fu
8、nctionality of network elements; it does not specify individual Ethernet transport network equipment. History Edition Recommendation Approval Study Group Unique ID* 1.0 ITU-T G.8021/Y.1341 2004-08-22 15 11.1002/1000/7364 1.1 ITU-T G.8021/Y.1341 (2004) Amd. 1 2006-06-06 15 11.1002/1000/8776 2.0 ITU-T
9、 G.8021/Y.1341 2007-12-22 15 11.1002/1000/9173 2.1 ITU-T G.8021/Y.1341 (2007) Amd. 1 2009-01-13 15 11.1002/1000/9661 2.2 ITU-T G.8021/Y.1341 (2007) Amd. 2 2010-02-22 15 11.1002/1000/10428 3.0 ITU-T G.8021/Y.1341 2010-10-22 15 11.1002/1000/10900 3.1 ITU-T G.8021/Y.1341 (2010) Amd. 1 2011-07-22 15 11.
10、1002/1000/11137 4.0 ITU-T G.8021/Y.1341 2012-05-07 15 11.1002/1000/11512 4.1 ITU-T G.8021/Y.1341 (2012) Amd. 1 2012-10-29 15 11.1002/1000/11777 4.2 ITU-T G.8021/Y.1341 (2012) Amd. 2 2013-08-29 15 11.1002/1000/12030 5.0 ITU-T G.8021/Y.1341 2015-04-06 15 11.1002/1000/12382 5.1 ITU-T G.8021/Y.1341 (201
11、5) Cor. 1 2015-08-13 15 11.1002/1000/12551 Keywords Atomic functions, equipment functional blocks, Ethernet transport 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:/
12、handle.itu.int/11.1002/1000/ 11830-en. ii Rec. ITU-T G.8021/Y.1341 (04/2015) 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 Standardizat
13、ion 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 telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which mee
14、ts 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 laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts
15、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 telecommunication administration and a recognized operating agency. Compliance with this Recommendation is
16、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 mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ a
17、nd 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 attention to the possibility that the practice or implementation of this Recommendation may inv
18、olve 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 others outside of the Recommendation development process. As of the date of approval of this Rec
19、ommendation, ITU had not 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 the latest information and are therefore strongly urged to consult the TSB patent database
20、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.8021/Y.1341 (04/2015) iii Table of Contents Page 1 Scope . 1 2 References . 3 3 Definitions 4 4 Abbreviatio
21、ns and acronyms 6 5 Methodology and conventions 12 6 Supervision . 12 6.1 Defects 12 6.2 Consequent actions . 21 6.3 Defect correlations 21 6.4 Performance filters . 21 7 Information flow across reference points . 21 8 Generic processes for Ethernet equipment . 21 8.1 OAM related processes . 21 8.2
22、Queueing process 114 8.3 Filter process 114 8.4 Replicate process 115 8.5 802.3 protocols processes . 115 8.6 MAC length check process . 118 8.7 MAC frame counter process . 119 8.8 Server-specific common processes . 119 8.9 QoS related processes . 122 9 Ethernet MAC layer (ETH) functions 124 9.1 ETH
23、 connection functions (ETH_C) 128 9.2 ETH termination functions . 139 9.3 ETH adaptation functions . 161 9.4 ETH diagnostic functions . 189 9.5 Server to ETH adaptation functions (/ETH_A) . 208 9.6 ETH traffic conditioning and shaping functions (ETH_TCS) . 210 9.7 ETH link aggregation functions . 21
24、5 9.8 ETH MEP and MIP functions 227 10 Ethernet PHY layer functions (ETYn) . 229 10.1 ETYn connection functions (ETYn_C) 229 10.2 ETYn trail termination functions (ETYn_TT) . 229 10.3 ETYn to ETH adaptation functions (ETYn/ETH_A) . 233 10.4 1000BASE-(SX/LX/CX) ETY to Coding sublayer adaptation funct
25、ions (ETY3/ETC3_A) 238 10.5 ETCn trail termination functions (ETCn_TT) 239 10.6 ETCn to ETH adaptation functions (ETCn/ETH_A) . 239 iv Rec. ITU-T G.8021/Y.1341 (04/2015) Page 10.7 ETY4 to Ethernet PP-OS adaptation function (ETY4/ETHPP-OS_A) 239 11 Non-Ethernet server to ETH adaptation functions . 24
26、2 11.1 SDH to ETH adaptation functions (S/ETH_A) 242 11.2 SDH to ETC adaptation functions (Sn-X/ETC3_A) 263 11.3 S4-64c to ETH-w adaptation functions 268 11.4 PDH to ETH adaptation functions (P/ETH_A) 268 11.5 OTH to ETH adaptation functions (O/ETH_A) . 281 11.6 MPLS to ETH adaptation functions (MPL
27、S/ETH_A) . 299 11.7 ATM VC to ETH adaptation functions (VC/ETH_A) . 299 11.8 RPR to ETH adaptation functions (RPR/ETH_A) . 299 Appendix I Applications and functional diagrams . 300 Appendix II AIS/RDI mechanism for an Ethernet private line over a single SDH or OTH server layer 302 Appendix III Compo
28、und functions . 306 Appendix IV Startup conditions . 307 Appendix V SDL descriptions 308 Appendix VI Calculation methods for frame loss measurement 309 VI.1 Dual-ended loss measurement 309 VI.2 Single-ended loss measurement . 309 Appendix VII Considerations of the support of a rooted multipoint EVC
29、service . 311 VII.1 Port group function . 311 VII.2 Configuration of asymmetric VLANs 312 Appendix VIII Configurations for ingress VID filtering 314 Appendix IX Handling of expected defects 315 IX.1 Interruption events 315 IX.2 Service activation . 316 IX.3 Additional considerations . 317 Bibliograp
30、hy. 318 Rec. ITU-T G.8021/Y.1341 (04/2015) v Introduction This Recommendation forms part of a suite of ITU-T Recommendations covering the full functionality of Ethernet transport network architecture and equipment (e.g., Recommendations ITU-T G.8010/Y.1306 and ITU-T G.8012/Y.1308) and follows the pr
31、inciples defined in Recommendation ITU-T G.805. This Recommendation specifies a library of basic building blocks and a set of rules by which they may be combined in order to describe equipment used in an Ethernet transport network. The building blocks are based on atomic modelling functions defined
32、in Recommendations ITU-T G.806 and ITU-T G.809. The library comprises the functional building blocks needed to wholly specify the generic functional structure of the Ethernet transport network. In order to be compliant with this Recommendation, the Ethernet functionality of any equipment which proce
33、sses at least one of the Ethernet transport layers needs to be describable as an interconnection of a subset of these functional blocks contained within this Recommendation. The interconnections of these blocks should obey the combination rules given. The specification method is based on functional
34、decomposition of the equipment into atomic and compound functions. The equipment is then described by its equipment functional specification (EFS) which lists the constituent atomic and compound functions, their interconnection and any overall performance objectives (e.g., transfer delay, availabili
35、ty, etc.). Rec. ITU-T G.8021/Y.1341 (04/2015) 1 Recommendation ITU-T G.8021/Y.1341 Characteristics of Ethernet transport network equipment functional blocks 1 Scope This Recommendation covers the functional requirements of Ethernet functionality within Ethernet transport equipment. This Recommendati
36、on uses the specification methodology defined in ITU-T G.806 in general for transport network equipment and is based on the architecture of Ethernet layer networks defined in ITU-T G.8010, the interfaces for Ethernet transport networks defined in ITU-T G.8012, and in support of services defined in I
37、TU-T G.8011. It also provides processes for Ethernet OAM based on ITU-T G.8013. The description is generic and no particular physical partitioning of functions is implied. The input/output information flows associated with the functional blocks serve for defining the functions of the blocks and are
38、considered to be conceptual, not physical. The functionality defined in this Recommendation can be applied at user-to-network interfaces (UNIs) and network-to-network interfaces (NNIs) of the Ethernet transport network. Not every functional block defined in this Recommendation is required for every
39、application. Different subsets of functional blocks from this Recommendation and others (e.g., ITU-T G.783, ITU-T G.798, ITU-T G.806 and b-ITU-T I.732) may be assembled in different ways according to the combination rules given in these Recommendations (e.g., ITU-T G.806) to provide a variety of dif
40、ferent capabilities. Network operators and equipment suppliers may choose which functions must be implemented for each application. The internal structure of the implementation of this functionality (equipment design) need not be identical to the structure of the functional model, as long as all the
41、 details of the externally observable behaviour comply with the equipment functional specification (EFS). Equipment developed prior to the production of this Recommendation may not comply with all the details in this Recommendation. The equipment requirements described in this Recommendation are gen
42、eric and no particular physical partitioning of functions is implied. The input/output information flows associated with the functional blocks define the functions of the blocks and are considered to be conceptual, not physical. Figure 1-1 presents a summary illustration of the set of atomic functio
43、ns associated with the Ethernet signal transport. These atomic functions may be combined in various ways to support a variety of Ethernet services, some of which are illustrated in Appendix I. In order to reduce the complexity of the figures, the functions for the processing of management communicat
44、ion channels (e.g., SDH DCC or OTH COMMS) are not shown. For DCC or COMMS functions, refer to the specific layer network descriptions. 2 Rec. ITU-T G.8021/Y.1341 (04/2015) Figure 1-1 Overview of ITU-T G.8021/Y.1341 atomic model functions Rec. ITU-T G.8021/Y.1341 (04/2015) 3 2 References The followin
45、g 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 Recommendations and other references are subject to revision; users of this Recommen
46、dation 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 published. The reference to a document within this Recommendation does not giv
47、e it, as a stand-alone document, the status of a Recommendation. 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.709/Y.1331 (2012), Interfaces for the optical transport network (OTN). ITU-T G
48、.783 Recommendation ITU-T G.783 (2006), Characteristics of synchronous digital hierarchy (SDH) equipment functional blocks. ITU-T G.798 Recommendation ITU-T G.798 (2012), Characteristics of optical transport network hierarchy equipment functional blocks. ITU-T G.805 Recommendation ITU-T G.805 (2000)
49、, 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.809 Recommendation ITU-T G.809 (2003), Functional architecture of connectionless layer networks. ITU-T G.832 Recommendation ITU-T G.832 (1998), Transport of SDH elements on PDH networks Frame and multiplexing structures. ITU-T G.7041 Recommendation ITU-T G.
