1、 International Telecommunication Union ITU-T G.870/Y.1352TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (10/2012) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Digital networks Optical transport networks SERIES Y: GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS
2、 AND NEXT-GENERATION NETWORKS Internet protocol aspects Transport Terms and definitions for optical transport networks Recommendation ITU-T G.870/Y.1352 ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS INTERNATIONAL TELEPHONE CONNECTIONS AND CIRCUITS G.100G
3、.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 CARRIER TELEPHONE SYSTEMS ON RADIO-RELAY OR SATELLITE LINKS AND INTE
4、RCONNECTION 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 G.800G.899 General aspects G.800G.809 Design objectives for digital networ
5、ks G.810G.819 Quality and availability targets G.820G.829 Network capabilities and functions G.830G.839 SDH network characteristics G.840G.849 Management of transport network G.850G.859 SDH radio and satellite systems integration G.860G.869 Optical transport networks G.870G.879DIGITAL SECTIONS AND D
6、IGITAL 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.9000G.9999 For furth
7、er details, please refer to the list of ITU-T Recommendations. Rec. ITU-T G.870/Y.1352 (10/2012) i Recommendation ITU-T G.870/Y.1352 Terms and definitions for optical transport networks Summary Recommendation ITU-T G.870/Y.1352 provides terms, definitions and abbreviations used in optical transport
8、network (OTN) Recommendations. It contains a list of the definitions and abbreviations introduced in Recommendations associated with optical transport networks, and can be considered a companion Recommendation to Recommendations ITU-T G.780/Y.1351 and ITU-T G.8081/Y.1353. This Recommendation does no
9、t include terms specific to the physical layer or synchronization. The goal of this Recommendation is to be a single normative source for terms in this subject area. History Edition Recommendation Approval Study Group 1.0 ITU-T G.870/Y.1352 2004-06-13 15 1.1 ITU-T G.870/Y.1352 (2004) Amd. 1 2005-06-
10、29 15 2.0 ITU-T G.870/Y.1352 2008-03-29 15 2.1 ITU-T G.870/Y.1352 (2008) Amd.1 2009-11-13 15 3.0 ITU-T G.870/Y.1352 2010-07-29 15 4.0 ITU-T G.870/Y.1352 2012-02-13 15 5.0 ITU-T G.870/Y.1352 2012-10-29 15 Keywords Acronyms, optical transport network, OTN, terminology, terms. ii Rec. ITU-T G.870/Y.135
11、2 (10/2012) 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 organ of ITU. ITU-T is responsi
12、ble 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 topics for study by the ITU-
13、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 prepared on a collaborative
14、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 Recommendation may contain certain mandat
15、ory 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 to express requirements. The
16、 use of such words does not suggest that compliance with the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTS ITU 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
17、 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 not received notice of intellectual propert
18、y, 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 2013 All rights reserved. N
19、o part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T G.870/Y.1352 (10/2012) 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 Abbr
20、eviations and acronyms 16 5 Conventions 18 Appendix I List of source Recommendations . 20 Bibliography. 21 Rec. ITU-T G.870/Y.1352 (10/2012) 1 Recommendation ITU-T G.870/Y.1352 Terms and definitions for optical transport networks 1 Scope This Recommendation contains a complete listing of the terms,
21、definitions and abbreviations introduced in the Recommendations associated with optical transport networks (OTNs). OTN terms specific to synchronization or physical layer characteristics are not a part of this Recommendation. 2 References The following ITU-T Recommendations and other references cont
22、ain 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 Recommendation are therefore encouraged to investigate th
23、e 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 give it, as a stand-alone document, the status of a
24、Recommendation. ITU-T G.709 Recommendation ITU-T G.709/Y.1331 (2009), Interfaces for the Optical Transport Network (OTN). ITU-T G.780 Recommendation ITU-T G.780/Y.1351 (2008), Terms and definitions for synchronous digital hierarchy (SDH) networks. ITU-T G.805 Recommendation ITU-T G.805 (2000), Gener
25、ic functional architecture of transport networks. ITU-T G.806 Recommendation ITU-T G.806 (2009), Characteristics of transport equipment Description methodology and generic functionality. ITU-T G.808.1 Recommendation ITU-T G.808.1 (2006), Generic protection switching Linear trail and subnetwork prote
26、ction. ITU-T G.872 Recommendation ITU-T G.872 (2001), Architecture of optical transport networks. ITU-T G.873.1 Recommendation ITU-T G.873.1 (2006), Optical Transport Network (OTN): Linear protection. ITU-T G.7710 Recommendation ITU-T G.7710/Y.1701 (2007), Common equipment management function requir
27、ements. ITU-T G.7712 Recommendation ITU-T G.7712/Y.1703 (2008), Architecture and specification of data communication network. ITU-T G.8081 Recommendation ITU-T G.8081/Y.1353 (2008), Terms and definitions for Automatically Switched Optical Networks (ASON). ITU-T G.8201 Recommendation ITU-T G.8201 (20
28、03), Error performance parameters and objectives for multi-operator international paths within the Optical Transport Network (OTN). ITU-T M.3010 Recommendation ITU-T M.3010 (2000), Principles for a telecommunications management network. ITU-T M.3013 Recommendation ITU-T M.3013 (2000), Considerations
29、 for a telecommunications management network. 2 Rec. ITU-T G.870/Y.1352 (10/2012) ITU-T X.700 Recommendation ITU-T X.700 (1992), Management framework for Open Systems Interconnection (OSI) for CCITT applications. 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses the following terms
30、defined elsewhere: 3.1.1 adaptation: ITU-T G.805. 3.1.2 adaptation function: ITU-T G.806. 3.1.3 adapted information: ITU-T G.805. 3.1.4 administrative domain: ITU-T G.805. 3.1.5 atomic function: ITU-T G.806. 3.1.6 automatic protection switching (APS): ITU-T G.780. 3.1.7 block: ITU-T G.780. 3.1.8 cha
31、racteristic information (CI): ITU-T G.805. 3.1.9 connection: ITU-T G.805. 3.1.10 connection function (C): ITU-T G.806. 3.1.11 connection point (CP): ITU-T G.806. 3.1.12 connection supervision: ITU-T G.805. 3.1.13 data communications channel (DCC): ITU-T G.780. 3.1.14 defect: ITU-T G.806. 3.1.15 erro
32、red block (EB): ITU-T G.780. 3.1.16 embedded control channel (ECC): ITU-T G.7712. 3.1.17 failure: ITU-T G.806. 3.1.18 fault: ITU-T G.806. 3.1.19 function: ITU-T G.806. 3.1.20 layer: ITU-T G.780. 3.1.21 link connection: ITU-T G.805. 3.1.22 managed object: ITU-T X.700. 3.1.23 management application fu
33、nction (MAF): ITU-T G.780. 3.1.24 management information (MI): ITU-T G.806. 3.1.25 member: ITU-T G.806. 3.1.26 message communication function: ITU-T M.3013. 3.1.27 multiplex section (MS): ITU-T G.780. 3.1.28 multiplex section overhead (MSOH): ITU-T G.780. 3.1.29 network: ITU-T G.805. 3.1.30 network
34、connection (NC): ITU-T G.805. 3.1.31 network element: ITU-T M.3010. Rec. ITU-T G.870/Y.1352 (10/2012) 3 3.1.32 network element function (NEF): ITU-T M.3010. 3.1.33 network node interface (NNI): ITU-T G.780. 3.1.34 operations systems function (OSF): ITU-T M.3010. 3.1.35 path: ITU-T G.806. 3.1.36 path
35、 overhead (POH): ITU-T G.780. 3.1.37 process: ITU-T G.806. 3.1.38 reference point: ITU-T G.780. 3.1.39 section: ITU-T G.806. 3.1.40 signal degrade (SD): ITU-T G.806. 3.1.41 signal fail (SF): ITU-T G.806. 3.1.42 subnetwork: ITU-T G.805. 3.1.43 subnetwork connection (SNC): ITU-T G.805. 3.1.44 synchron
36、ous transport module (STM): ITU-T G.780. 3.1.45 telecommunications management network: ITU-T M.3010. 3.1.46 trail: ITU-T G.805. 3.1.47 trail termination function (TT): ITU-T G.806. 3.1.48 unequipped VC: ITU-T G.780. 3.1.49 unprotected: ITU-T G.780. 3.2 Terms defined in this Recommendation This Recom
37、mendation defines the following terms: 3.2.1 1+1 (protection) architecture: A 1+1 protection architecture has one normal traffic signal, one working transport entity, one protection transport entity and a permanent bridge. At the source end, the normal traffic signal is permanently bridged to both t
38、he working and the protection transport entities. At the sink end, the normal traffic signal is selected from the better of the two transport entities. Due to the permanent bridging, the 1+1 (protection) architecture does not allow an unprotected extra traffic signal to be provided. 3.2.2 1:n (prote
39、ction) architecture (n 1): A 1:n protection architecture has n normal traffic signals, n working transport entities and one protection transport entity. It may have one extra traffic signal. At the source end, a normal traffic signal is either permanently connected to its working transport entity an
40、d may be connected to the protection transport entity (in the case of a broadcast bridge), or is connected to either its working or the protection transport entity (in the case of a selector bridge). At the sink end, the normal traffic signal is selected from either the working or the protection tra
41、nsport entity. An unprotected extra traffic signal can be transported via the protection transport entity, whenever the protection transport entity is not used to carry a normal traffic signal. 3.2.3 (1:1)nprotection architecture: n parallel 1:1 protection architectures, which have their n protectio
42、n transport entities share (and compete for) the protection bandwidth. It has n normal traffic signals, n working transport entities and n protection transport entities. It may have an extra traffic signal, in which case an additional protection transport entity will be present. 4 Rec. ITU-T G.870/Y
43、.1352 (10/2012) NOTE This architecture is applicable in cell/packet layer networks (e.g., ATM, MPLS). 3.2.4 access function (AC): An access function provides access (add, drop and continue) at CPs to communication channels transported in the overhead. 3.2.5 active transport entity: The transport ent
44、ity from which the protection selector selects the normal traffic signal. 3.2.6 adaptation management: The set of processes for managing client-layer network adaptation to/from the server-layer network. 3.2.7 APS-byte pass-through: The action of transmitting the same APS-bytes that are being receive
45、d. Protection channels are not passed through. APS-byte pass-through is bidirectional. 3.2.8 APS channel: The automatic protection switch (APS) channel is used to carry information between the two ends of a linear protection group to coordinate the head-end bridge with the tail-end selector for 1:n
46、protection, and to coordinate the selectors in both directions in the case of bidirectional protection. 3.2.9 APS protocol: 1-phase: A means to align the two ends of the protected domain via the exchange of a single message (Z A). For (1:1)narchitectures, the bridge/selector at Z are operated before
47、 it is known if Zs condition has priority over the condition at A. When A confirms the priority of the condition at Z, it operates the bridge and selector. For unidirectional switching, the priority is determined by Z only and the selector at Z and bridge at A are operated. For 1+1 architectures, th
48、e bridges are permanent and only the selectors are to be operated. 3.2.10 APS protocol: 2-phase: A means to align the two ends of the protected domain via the exchange of two messages (Z A, A Z). For (1:1)narchitectures, Z signals the switch condition to A and operates the bridge. When A confirms th
49、e priority of the condition at Z, it operates the bridge and selector. On receipt of confirmation, Z operates its selector. For unidirectional switching, the priority is determined by Z only and the selector at Z and bridge at A are operated. For 1+1 architectures, the bridges are permanent and only the selectors are to be operated. 3.2.11 APS protocol: 3-phase: A means to align the two ends of the protected domain
