1、INTERNATIONAL TELECOMMUNICATION UNIONITU-TG.774.1TELECOMMUNICATIONSTANDARDIZATION SECTOROF ITU(02/2001)SERIES G: TRANSMISSION SYSTEMS AND MEDIA,DIGITAL SYSTEMS AND NETWORKSDigital terminal equipments Operations, administrationand maintenance features of transmission equipmentSynchronous digital hier
2、archy (SDH)bidirectional performance monitoring for thenetwork element viewCAUTION !PREPUBLISHED RECOMMENDATIONThis prepublication is an unedited version of a recently approved Recommendation.It will be replaced by the published version after editing. Therefore, there will bedifferences between this
3、 prepublication and the published version.FOREWORDThe International Telecommunication Union (ITU) is the United Nations specialized agency in the field oftelecommunications. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ ofITU. ITU-T is responsible for studying technic
4、al, operating and tariff questions and issuingRecommendations 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 tu
5、rn, produce Recommendations onthese 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 areprepared on a collaborative basis with ISO and IEC.NOTEIn t
6、his Recommendation, the expression “Administration“ is used for conciseness to indicate both atelecommunication administration and a recognized operating agency.INTELLECTUAL PROPERTY RIGHTSITU draws attention to the possibility that the practice or implementation of this Recommendation mayinvolve th
7、e 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 othersoutside of the Recommendation development process.As of the date of approval of this Recommendatio
8、n, ITU had/had not received notice of intellectualproperty, protected by patents, which may be required to implement this Recommendation. However,implementors are cautioned that this may not represent the latest information and are therefore stronglyurged to consult the TSB patent database. ITU 2001
9、All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means,electronic or mechanical, including photocopying and microfilm, without permission in writing from ITU.ITU-T G.774.1 (02/2001) Prepublished version 1RECOMMENDATION G.774.01“SYNCHRONOUS DIGITAL
10、HIERARCHY (SDH) BIDIRECTIONALPERFORMANCE MONITORING FOR THE NETWORK ELEMENT VIEW”SummaryThis Recommendation provides an information model for the Performance Monitoring ofSynchronous Digital hierarchy (SDH) Network. This model describes the managed object classesand their properties for the performa
11、nce monitoring function, as defined in Recommendation G.784and as related to SDH Network Elements. These objects are useful to describe informationexchanged across interfaces defined in M.3010 Telecommunications Management Network (TMN)architecture for the management of the performance monitoring fu
12、nction.1. ScopeSDH Performance Monitoring Functions are used to monitor specified performance events ofspecified Termination Points managed objects and to report these performance data, as well asQuality of Service Alarms to its managing system according to a given schedule.This Recommendation is fo
13、r bi-directional performance management of SDH path only.Recommendation M.2120 defines maintenance of transport network, Recommendation G.784defines the management of SDH based network element. This Recommendation defines the objectmodel based on Recommendation Q.822 according to the requirements de
14、scribed inRecommendations G.784 and M.2120. This model uses generic mechanisms defined inRecommendation Q.822.Structure of this RecommendationSubclause 5.1 provides an overview of the SDH performance monitoring information model.Clauses 6 to 15 describe the information model using the notation mecha
15、nisms defined in X.722Guidelines for the Definition of Managed Objects. Clause 15 contains the syntax definitions of theinformation carried in the protocol using Abstract Syntax Notation One (ASN.1) defined inRecommendation X.680 - X.683. Naming and Inheritance are illustrated in informative Annex A
16、.Diagrams illustrating the Threshold Reset behaviour are provided in informative Annex B. Clauses5 to 15 are normative; all other text is informative.2. ReferencesThe following Recommendations and other references contain provisions which, through referencein this text, constitute provisions of this
17、 Recommendation. At the time of publication, the editionsindicated were valid. All Recommendations and other references are subject to revision: all users ofthis Recommendation are therefore encouraged to investigate the possibility of applying the mostrecent edition of the Recommendations and other
18、 references listed below. A list of the currentlyvalid ITU-T Recommendations is regularly published. ITU-T Recommendation G.707 (2000), Network-node interface for the synchronous digitalhierarchy. ITU-T Recommendation G.773 (1993), Q-Interface protocols.ITU-T G.774.1 (02/2001) Prepublished version 2
19、 ITU-T Recommendation G.774 (2000), SDH management information model for the networkelement view. ITU-T Recommendation G.783 (1998), Characteristics of Synchronous Digital Hierarchy(SDH) equipment functional blocks. ITU-T Recommendation G.784 (1999), Synchronous Digital Hierarchy (SDH) management. I
20、TU-T Recommendation G.803 (1997), Architectures of transport networks based on thesynchronous digital hierarchy (SDH). ITU-T Recommendation G.831 (1996), Management capabilities of transport networks basedon the synchronous digital hierarchy (SDH). ITU-T Recommendation G.958 (1994), Digital line sys
21、tems based on SDH for use on opticalfibre cables. ITU-T Recommendation M.60 (1993), Maintenance terminology and definitions. ITU-T Recommendation M.2120 (1997), Digital path, section and transmission system faultdetection and localisation procedures. ITU-T Recommendation M.3010 (2000), Principles fo
22、r a telecommunication managementnetwork. ITU-T Recommendation M.3013 (2000), Considerations for a TelecommunicationsManagement Network. ITU-T Recommendation M.3100 (1995), Generic network information model. ITU-T Recommendation Q.811 (1990), Q3-Lower layers protocols. ITU-T Recommendation Q.812 (199
23、0), Q3-Higher layers protocols. ITU-T Recommendation Q.822 (1993), Stage 1, Stage 2 and Stage 3 description for theQ3-interface: performance management. ITU-T Recommendation X.680 - X.683 (1997), Specification of Abstract Syntax Notation One(ASN.1). ITU-T Recommendation X.701(1997) , Systems managem
24、ent overview. ITU-T Recommendation X.710 (1997), Common management information service. ITU-T Recommendation X.711(1997), Common management information protocol. ITU-T Recommendation X.720 (1992) and Amd.1 (95) and Corr.1 (94), Informationtechnology OSI Structure of Management Information: Managemen
25、t information model. ITU-T Recommendation X.721 (1993) and Corr. 1, 2, 3, and 4, Definition of managementinformation. ITU-T Recommendation X.722 (1992) and Amd.1 (95), Amd.2 (97), Amd.2 (97) and Corr.1(96), Information technology OSI Structure of management information: Guidelines forthe definition
26、of managed objects. ITU-T Recommendation X.730 (1992) and Amd.1 (95) and Corr1Amd1 (96), Objectmanagement function. ITU-T Recommendation X.731 (1992) and Amd.1 (95), Corr.1 (95) and Corr1Amd1 (96),State management function. ITU-T Recommendation X.733 (1992) and Corr.1 (94), Amd1 (95), Corr1Amd1 (96)
27、 andCorr.2 (99), Alarm reporting function.ITU-T G.774.1 (02/2001) Prepublished version 3 ITU-T Recommendation X.734 (1992) and Corr.1 (94), Amd1 (95), Corr1Amd1 (96) andCorr.2 (99), Event report management function. ITU-T Recommendation X.735 (1992) and Amd.1 (95) and Corr1Amd1 (96), Log controlfunc
28、tion. ITU-T Recommendation X.739 (1993), Information technology Open SystemsInterconnection Systems Management Metric objects and attributes.3. Terms and DefinitionsThis Recommendation uses the terms and definitions defined in Recommendations G.784, G.774and M.3100.4. AbbreviationsFor the purpose of
29、 this Recommendation, the following abbreviations are used:AIS Alarm Indication SignalBBE Background Block ErrorCSES Consecutive Severely Errored SecondCTP Connection Termination PointEBER Excessive Bit Error RatioES Errored SecondFEBBE Far End Background Block ErrorFEEB Far End Errored BlockFEES Fa
30、r End Errored SecondFERF Far End Receive FailureFESES Far End Severely Errored SecondISO International Organisation for StandardizationITU International Telecommunications UnionLB Laser BiasLOF Loss of FrameLOS Loss of SignalLT Laser TemperatureMS Multiplex SectionNCSES Number of Consecutive Severel
31、y Errored SecondNE Network ElementOFS Out of Frame SecondOOF Out of FrameOS Operations SystemOSI Open Systems InterconnectionOSL Optical Signal LevelPJC Pointer Justification CountITU-T G.774.1 (02/2001) Prepublished version 4PJE Pointer Justification EventPkg PackagePPI Plesiochronous Physical Inte
32、rfacePSC Protection Switch CountPSD Protection Switch DurationQOS Quality of ServiceRAI Remote Alarm IndicationRDN Relative Distinguished NameRS Regenerator sectionSDH Synchronous Digital HierarchySES Severely Errored SecondSPI Synchronous Physical InterfaceSTM-N Synchronous Transport Module NTMN Te
33、lecommunications Management NetworkTP Termination PointTR Threshold ResetTTP Trail Termination PointUAS Unavailable Second5. Performance Management Model5.1 OverviewThis clause provides Managed Objects required to support management of performance monitoringin SDH Network Elements.This model defines
34、 subclasses of the generic currentData and historyData object classes fromRecommendation Q.822, for each kind of monitoring point. For each type of monitoring point twosubclasses of currentData are defined. One is defined for either a 15 minute count or 1 day countperiod, and provides implicit clear
35、ing of threshold crossing alarms at the end of each granularityperiod. The other subclass is only relevant to 15 minute counting and performs explicit clearing ofthreshold alarms (Threshold Reset) at the end of a clear 15 minute period (refer to 2.3.4.2/M.2120).Starting and ending of unavailibilty p
36、eriod is reported by the instances of these subclasses that holdthe 24-hour counts.History information could either be collected as part of historyData instances or one of itssubclasses or as an eventRecord or one of its subclasses contained in a log. Utilization of a LOG isnot mandatory in this Rec
37、ommendation.The threshold reset (TR) mechanism used in this Recommendation corresponds to the resetthreshold report (RTR) of G.784.5.2 RequirementsThe SDH Performance Monitoring functions shall provide for:ITU-T G.774.1 (02/2001) Prepublished version 5 the ability for a managing system to request th
38、e collection of the various Performanceevents relating to a given monitored entity for a given collection period; the ability for a managing system to suspend/resume the performance data collection for agiven monitored entity (or set of entities); the ability for a managing system to instruct the NE
39、 to reset the performance monitoringcounters for a given monitored entity (or set of entities); the scheduling of performance collection activity within specified time periods, for a givenmonitored entity (or set of entities); the ability for a managing system to request the performance monitoring c
40、ounters for agiven monitored entity (or set of entities); the ability for a managed system to send event reports to a managing system to notify theresults of the performance data collection, at the end of the collection period; the ability for a managing system to instruct the NE to maintain Perform
41、ance historical datafor a specified duration, under specified conditions; the ability for a managing system to instruct the NE to remove specific Performancehistorical data; the ability for a managing system to instruct the NE to establish thresholding criteria for agiven monitored entity (or set of
42、 entities); the ability for a managed system to send Quality of Service Alarms upon threshold violationof a performance counter of a monitored entity.6. Managed Object Classes DefinitionsNote 1: See Appendix C for a list of the managed object classes that have been moved to G.774-6for unidirectional
43、 performance monitoring.Note 2: See Appendix D for the managed object classes that are no longer required.6.1 SDH Current DatasdhCurrentData MANAGED OBJECT CLASSDERIVED FROM “Recommendation Q.822“ : currentData;CHARACTERIZED BY“Recommendation Q.822“: zeroSuppressionPkg,“Recommendation Q.822“: thresh
44、oldPkg,sdhCurrentDataPackage PACKAGEBEHAVIOUR sdhCurrentDataBehaviour;ATTRIBUTES“Recommendation M.3100“: currentProblemList GET;CONDITIONAL PACKAGEShistoryPackage PRESENT IF“an instance does not support flexible assignment of the history length“,unavailableTimeAlarmPackage PRESENT IF“starting and en
45、ding of unavailable period has to be reported and thegranularity period is 24 hours“;REGISTERED AS g774-01MObjectClass 1;sdhCurrentDataBehaviour BEHAVIOURDEFINED AS“The sdhCurrentData class is used to define generic characteristic for SDH performance monitoring from whichsubclasses are defined in or
46、der to hold performance event counts for a specific monitoring point. Subclasses of thisclass are used in order to support performance monitoring of SDH paths at various layers as described inRecommendation G.803. The performance monitoring events ES, SES and BBE which are monitored by some of thesu
47、bclasses of this subclass are defined in 4.1.1/G.826. The granularityPeriod attribute can only be assigned a value atcreation time.ITU-T G.774.1 (02/2001) Prepublished version 6This class can only contain one reference to an instance of the thresholdData object class in the thresholdDataInstanceattr
48、ibute.The 15 and 24 hours granularity period must be supported fully. If a threshold is reached or crossed then thecurrentProblemList attribute shall indicate it with the probable cause Threshold crossed. Subclass of this class is usedto monitor the near end of the path in case of bidirectional path
49、 the far end of the path shall be supported additionaly. Incase of monitoring of a bidirectional path and Far End unavailability is monitored, an unavailable period starts if eitherthe near end or the far end is in a unavailable condition. In case of monitoring of a unidirectional path only the near endis considered.An unavailable condition starts when 10 consecutive severely errored seconds have been detected; these 10 secondsbelong to the unavailable time. An unavailable condition ends when 10 consecutive seconds w
