SIST EN 300 462-7-1 V1.1.2:2003

• Abstract:

  Standardize timing characteristics of slave clocks suitable for synchronization supply to equipment in local node applications

• Status: Published
• Publication Date: 30-Nov-2003
• ICS: 33.040.20 - Transmission systems
• Technical Committee: SS EIT - Technical Board for the electrotechnical, information technology and telecommunications fields
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Dec-2003
• Due Date: 01-Dec-2003
• Completion Date: 01-Dec-2003
• Ref Project: ETSI EN 300 462-7-1 V1.1.2 (2001-06) - Transmission and Multiplexing (TM); Generic requirements for synchronization networks; Part 7-1: Timing characteristics of slave clocks suitable for synchronization supply to equipment in local node applications

SIST EN 300 462-7-1 V1.1.2:2003 is the Slovene adoption of ETSI EN 300 462-7-1 Version 1.1.2 for timing characteristics of slave clocks used to provide synchronization to equipment in local node applications. It specifies the minimum performance of a Synchronization Supply Unit for local node applications (SSU-L) in Synchronous Digital Hierarchy (SDH), Public Switched Telephone Network (PSTN) and Public Land Mobile Networks (PLMN) use.

What does SIST EN 300 462-7-1 V1.1.2:2003 specify?

SIST EN 300 462-7-1 V1.1.2:2003 specifies requirements for SSU-Ls, the last synchronization supply unit in a synchronization chain for local node applications. The document is aimed at new synchronization network design and sets performance limits that help a designer, buyer or tester judge whether an SSU-L can supply stable timing to network equipment.

The scope links the SSU-L to SDH transport networks, PSTN and PLMN equipment. It also notes that the same logical function can be built as a stand-alone unit called a Stand-Alone Synchronization Equipment (SASE) or embedded in other equipment such as a telephony exchange or an SDH cross-connect.

The document is organized into clauses 4 to 10 and Annex A.

• Clause 4 - frequency accuracy
• Clause 5 - pull-in and pull-out ranges
• Clause 6 - noise generation
• Clause 7 - noise tolerance
• Clause 8 - transfer characteristic
• Clause 9 - transient response and holdover performance
• Clause 10 - interfaces
• Annex A - bibliography

It also states that the requirements apply under environmental classes from ETS 300 019 unless stated otherwise, so the manufacturer must identify the relevant operating class.

What are the key requirements of SIST EN 300 462-7-1 V1.1.2:2003?

Steady-state timing performance

Clause 4 covers long-term frequency accuracy, with the note that an SSU-L normally operates locked or in holdover rather than as a free-running clock. For a user, this means the clock has to stay within its declared timing behavior after the synchronization reference is removed.

Clause 5 defines the minimum pull-in range and leaves pull-out for further study. In practice, this is the part to check when you need the SSU-L to acquire synchronization from a reference that is not exactly on frequency.

Noise generation, jitter and wander

Clause 6 describes noise generation in terms of phase noise at the output and uses Maximum Time Interval Error (MTIE) and Time DEViation (TDEV) as the main measures. It also defines the measurement approach, including a 10 Hz equivalent first-order low-pass filter and a maximum sampling time, so test results are comparable between laboratories.

Clause 6 separates locked-mode wander and output jitter by interface type. The practical point is that the same SSU-L has to meet different output masks depending on whether you measure a 2048 kHz, 2048 kbit/s or STM-N interface.

Clause 7 sets input noise tolerance for jitter and wander. This is important because the SSU-L must survive noisy synchronization inputs without alarming, switching reference or falling into holdover too early.

Transfer and disturbance behavior

Clause 8 treats the SSU-L as a controlled transfer element for input phase variations. In practice, this means the clock must not pass input phase disturbances straight through to the output, and its transfer behavior is bounded.

Clause 9 covers reference switching, holdover, input interruptions and internal disturbances. For operators, this is the section that matters during failures, restoration events and internal protection switching because it limits phase jumps and drift while the clock changes reference or runs without one.

Clause 10 identifies the external synchronization interfaces to which the requirements apply: 2048 kHz, 2048 kbit/s and STM-N. That tells implementers which ports need to be assessed against the timing masks.

What terms does SIST EN 300 462-7-1 V1.1.2:2003 define?

• Synchronization Supply Unit for local node applications (SSU-L) - the slave clock function covered by this document, used at the end of a synchronization chain for local node equipment.
• Locked mode - the operating state where the SSU-L is synchronized to a timing reference.
• Holdover - the state where the SSU-L continues running after loss of reference while staying within specified limits.
• Maximum Time Interval Error (MTIE) - a measure used here to characterize wander over an observation interval.
• Time DEViation (TDEV) - a measure used here to characterize timing variation over an observation interval.
• Synchronous Transport Module-N (STM-N) - the SDH interface family for which separate output jitter limits are given.
• Stand-Alone Synchronization Equipment (SASE) - a separate equipment implementation of the SSU-L function.

Who uses SIST EN 300 462-7-1 V1.1.2:2003?

This standard is used by synchronization network designers, telecom equipment manufacturers, test laboratories and network operators. It is relevant when specifying or checking local node clocks for SDH transport, PSTN switching and PLMN infrastructure.

It is also useful for engineers working on telephony exchanges, SDH cross-connects, Base Station Controllers (BSC), Mobile Switching Centres (MSC) and other equipment that needs a stable synchronization source. Quality managers and buyers use it to compare declared timing performance with the required masks and operating conditions.

What changed in SIST EN 300 462-7-1 V1.1.2:2003 from the previous edition?

The document history shows an earlier version, V1.1.1, followed by this V1.1.2 edition. The provided document history does not state the detailed technical changes.

Which standards are used with SIST EN 300 462-7-1 V1.1.2:2003?

• ETS 300 019 - defines the environmental classes and environmental test conditions referenced by the scope.
• EN 300 462-1-1 - provides the common definitions and terminology used by this part.
• EN 300 462-2-1 - gives the synchronization network architecture and the SSU logical function.
• EN 300 462-3-1 - provides the control of jitter and wander within synchronization networks and measurement guidance.
• EN 300 462-4-1 - covers slave clocks for synchronization supply to SDH and PDH equipment.
• EN 300 462-5-1 - covers slave clocks for operation in SDH equipment and includes guidance on timing measurement.
• TS 100 912 - relates this clock type to GSM radio subsystem synchronization.
• ETS 300 166 - defines the 2048 kbit/s-based hierarchical digital interfaces used for some external ports.
• ITU-T Recommendation G.825 - gives jitter and wander control for SDH-based digital networks.
• ITU-T Recommendation G.823 - gives jitter and wander control for 2048 kbit/s hierarchy networks.
• ITU-T Recommendation O.172 - describes jitter and wander measuring equipment for SDH systems.

What does the SIST EN 300 462-7-1 V1.1.2:2003 document contain?

The document contains requirement clauses, masks, measurement conditions and explanatory figures for SSU-L timing behavior. It uses tables and figures to show wander, jitter and transient-response limits, rather than describing them only in prose.

Clauses 6 to 9 are the core technical parts, with graphs for MTIE, TDEV, jitter tolerance and wander tolerance, and with a formula-based holdover description. These are the parts used for design verification, type testing and conformance assessment of synchronization equipment.

Annex A gives a bibliography for related synchronization standards and recommendations.

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Transmission and Multiplexing (TM); Generic requirements for synchronization networks; Part 7-1: Timing characteristics of slave clocks suitable for synchronization supply to equipment in local node applications33.040.20Prenosni sistemTransmission systemsICS:Ta slovenski standard je istoveten z:EN 300 462-7-1 Version 1.1.2SIST EN 300 462-7-1 V1.1.2:2003en01-december-2003SIST EN 300 462-7-1 V1.1.2:2003SLOVENSKI
STANDARD
ETSIEN300462-7-1V1.1.2(2001-06)EuropeanStandard(Telecommunicationsseries)TransmissionandMultiplexing(TM);Genericrequirementsforsynchronizationnetworks;Part7-1:TimingcharacteristicsofslaveclockssuitableforsynchronizationsupplytoequipmentinlocalnodeapplicationsSIST EN 300 462-7-1 V1.1.2:2003

ETSIETSIEN300462-7-1V1.1.2(2001-06)2ReferenceDEN/TM-01057-7-1Keywordsnetwork,synchronization,transmissionETSI650RoutedesLuciolesF-06921SophiaAntipolisCedex-FRANCETel.:[phone]Fax:[phone]SiretN°34862356200017-NAF742CAssociationàbutnonlucratifenregistréeàlaSous-PréfecturedeGrasse(06)N°7803/88ImportantnoticeIndividualcopiesofthepresentdocumentcanbedownloadedfrom:http://www.etsi.orgThepresentdocumentmaybemadeavailableinmorethanoneelectronicversionorinprint.Inanycaseofexistingorperceiveddifferenceincontentsbetweensuchversions,thereferenceversionisthePortableDocumentFormat(PDF).Incaseofdispute,thereferenceshallbetheprintingonETSIprintersofthePDFversionkeptonaspecificnetworkdrivewithinETSISecretariat.Usersofthepresentdocumentshouldbeawarethatthedocumentmaybesubjecttorevisionorchangeofstatus.InformationonthecurrentstatusofthisandotherETSIdocumentsisavailableathttp://www.etsi.org/tb/status/Ifyoufinderrorsinthepresentdocument,sendyourcommentto:[e-mail]opartmaybereproducedexceptasauthorizedbywrittenpermission.Thecopyrightandtheforegoingrestrictionextendtoreproductioninallmedia.©EuropeanTelecommunicationsStandardsInstitute2001.Allrightsreserved.SIST EN 300 462-7-1 V1.1.2:2003

ETSIETSIEN300462-7-1V1.1.2(2001-06)3ContentsIntellectualPropertyRights.4Foreword.41Scope.52References.53Definitionsandabbreviations.63.1Definitions.63.2Abbreviations.64Frequencyaccuracy.75Pull-inandpull-outranges.76Noisegeneration.76.1Wanderinlockedmode.76.2Non-lockedwander.96.3Jitter.96.3.1Outputjitterata2048kHzand2048kbit/sinterface.96.3.2OutputjitterataSynchronousTransportModuleN(STM-N)interface.97Noisetolerance.107.1Jittertolerance.107.2Wandertolerance.118Transfercharacteristic.139Transientresponseandholdoverperformance.139.1Phaseresponseduringinputreferenceswitching.139.2PhaseresponseduringHold-overoperation.149.3Phaseresponsetoinputsignalinterruptions.149.4Phasediscontinuity.1510Interfaces.15AnnexA(informative):Bibliography.16History.17SIST EN 300 462-7-1 V1.1.2:2003

ETSIETSIEN300462-7-1V1.1.2(2001-06)4IntellectualPropertyRightsIPRsessentialorpotentiallyessentialtothepresentdocumentmayhavebeendeclaredtoETSI.TheinformationpertainingtotheseessentialIPRs,ifany,ispubliclyavailableforETSImembersandnon-members,andcanbefoundinETSISR000314:"IntellectualPropertyRights(IPRs);Essential,orpotentiallyEssential,IPRsnotifiedtoETSIinrespectofETSIstandards",whichisavailablefromtheETSISecretariat.LatestupdatesareavailableontheETSIWebserver(http://www.etsi.org/ipr).PursuanttotheETSIIPRPolicy,noinvestigation,includingIPRsearches,hasbeencarriedoutbyETSI.NoguaranteecanbegivenastotheexistenceofotherIPRsnotreferencedinETSISR000314(ortheupdatesontheETSIWebserver)whichare,ormaybe,ormaybecome,essentialtothepresentdocument.ForewordThisEuropeanStandard(Telecommunicationsseries)hasbeenproducedbyETSITechnicalCommitteeTransmissionandMultiplexing(TM).Thepresentdocumentispart7-1ofamulti-partdeliverablecoveringTransmissionandMultiplexing(TM);Genericrequirementsforsynchronizationnetworks,asidentifiedbelow:Part1-1:"Definitionsandterminologyforsynchronizationnetworks";Part2-1:"Synchronizationnetworkarchitecture";Part3-1:"Thecontrolofjitterandwanderwithinsynchronizationnetworks";Part4-1:"TimingcharacteristicsofslaveclockssuitableforsynchronizationsupplytoSynchronousDigitalHierarchy(SDH)andPlesiochronousDigitalHierarchy(PDH)equipment";Part4-2:"TimingcharacteristicsofslaveclockssuitableforsynchronizationsupplytoSynchronousDigitalHierarchy(SDH)andPlesiochronousDigitalHierarchy(PDH)equipment;ImplementationConformanceStatement(ICS)proformaspecification";Part5-1:"TimingcharacteristicsofslaveclockssuitableforoperationinSynchronousDigitalHierarchy(SDH)equipment";Part6-1:"Timingcharacteristicsofprimaryreferenceclocks".Part6-2:"Timingcharacteristicsofprimaryreferenceclocks;ImplementationConformanceStatement(ICS)proformaspecification";Part7-1:"Timingcharacteristicsofslaveclockssuitableforsynchronizationsupplytoequipmentinlocalnodeapplications".NationaltranspositiondatesDateofadoptionofthisEN:1June2001DateoflatestannouncementofthisEN(doa):30September2001DateoflatestpublicationofnewNationalStandardorendorsementofthisEN(dop/e):31March2002DateofwithdrawalofanyconflictingNationalStandard(dow):31March2002SIST EN 300 462-7-1 V1.1.2:2003

ETSIETSIEN300462-7-1V1.1.2(2001-06)51ScopeThepresentdocumentoutlinesrequirementsfortimingdevicescalledSynchronizationSupplyUnitsforlocalnodeapplications(SSU-Ls).ThisSSUisusedinsynchronizingnetworkequipmentintheSynchronousDigitalHierarchy(SDH)transportnetwork,inthePublicSwitchedTelephoneNetwork(PSTN)andinthePublicLandMobileNetworks(PLMN)forlocalnodeapplications.ThelastSSUinaSynchronizationchain,irrespectiveofthetrafficnetwork,providestheapplicationsforthistypeofclock.NOTE:TherequirementsinthepresentdocumentapplyunderenvironmentalconditionsaccordingtooneoftheenvironmentalclassesdefinedinETS300019[1],unlessstatedotherwise.Themanufacturerwillneedtospecifytowhichspecificenvironmentalclasstheequipmentbelongs.AdescriptionoftheSynchronizationSupplyUnit(SSU)logicalfunctionisgiveninfigure1inEN300462-2-1[3].Ingeneral,theSSUwillhavemultipletimingreferenceinputsandintheeventthatalltimingreferencesfail,theSSUshouldbecapableofmaintainingoperation(holdover)withinprescribedperformancelimitsasdetailedinthepresentdocument.TherequirementslaiddowninthepresentdocumentdescribetheminimumperformanceofanSSUappliedasalocalnodeclock(SSU-L).RequirementsfortransitnodeclockapplicationsforSSU'saredescribedinEN300462-4-1[5].TheSSU-LfunctioncanbeimplementedinaseparatepieceofequipmentcalledaStand-AloneSynchronizationEquipment(SASE)oritcanformalogicalfunctionofanotherequipmentsuchasatelephonyexchangeoranSDHcross-connect.Therequirementsspecifiedinthepresentdocumentrefertothedesignofnewsynchronizationnetworksandconsequentlytheydonotnecessarilyrepresenttheperformanceofexistingsynchronizationnetworkandequipment.AtimingdevicewithinSDHequipmentcanalsoconformtoEN300462-5-1[6].ThecharacteristicsrelatedtoholdoverandnoisegenerationperformancemakethistypeofclockalsosuitableforapplicationintheGSMradiosub-system(seeTS100912[7]).InparticularasaclockusedbyaBaseStationController(BSC)orbyaMobileSwitchingCentre(MSC),furthersynchronizing(typicallyviaatrafficlink)theBaseStation(BS).ThecharacteristicsofthisclockarenotoptimizedforaclocktobeimplementedintheBS.InordertofulfilthefrequencyaccuracyrequirementsrequiredintheGSMradiointerface,thisclockshouldbeconnectedtoasynchronizationnetworkthatisproperlydesignedandcorrectlyoperating.2ReferencesThefollowingdocumentscontainprovisionswhich,throughreferenceinthistext,constituteprovisionsofthepresentdocument.• Referencesareeitherspecific(identifiedbydateofpublicationand/oreditionnumberorversionnumber)ornon-specific.• Foraspecificreference,subsequentrevisionsdonotapply.• Foranon-specificreference,thelatestversionapplies.[1]ETSIETS300019:"EquipmentEngineering(EE);Environmentalconditionsandenvironmentaltestsfortelecommunicationsequipment".[2]ETSIEN300462-1-1:"TransmissionandMultiplexing(TM);Genericrequirementsforsynchronizationnetworks;Part1-1:Definitionsandterminologyforsynchronizationnetworks".[3]ETSIEN300462-2-1:"TransmissionandMultiplexing(TM);Genericrequirementsforsynchronizationnetworks;Part2-1:Synchronizationnetworkarchitecture".SIST EN 300 462-7-1 V1.1.2:2003

ETSIETSIEN300462-7-1V1.1.2(2001-06)6[4]ETSIEN300462-3-1:"TransmissionandMultiplexing(TM);Genericrequirementsforsynchronizationnetworks;Part3-1:Thecontrolofjitterandwanderwithinsynchronizationnetworks".[5]ETSIEN300462-4-1:"TransmissionandMultiplexing(TM);Genericrequirementsforsynchronizationnetworks;Part4-1:TimingcharacteristicsofslaveclockssuitableforsynchronizationsupplytoSynchronousDigitalHierarchy(SDH)andPlesiochronousDigitalHierarchy(PDH)equipment".[6]ETSIEN300462-5-1:"TransmissionandMultiplexing(TM);Genericrequirementsforsynchronizationnetworks;Part5-1:TimingcharacteristicsofslaveclockssuitableforoperationinSynchronousDigitalHierarchy(SDH)equipment".[7]ETSITS100912(GSM05.10):"Digitalcellulartelecommunicationssystem(Phase2+);Radiosubsystemsynchronization(3GPPTS05.10version8.8.0Release1999)".[8]ETSIETS300166:"TransmissionandMultiplexing(TM);Physicalandelectricalcharacteristicsofhierarchicaldigitalinterfacesforequipmentusingthe2048kbit/s-basedplesiochronousorsynchronousdigitalhierarchies".[9]ITU-TRecommendationG.825:"Thecontrolofjitterandwanderwithindigitalnetworkswhicharebasedonthesynchronousdigitalhierarchy(SDH)".[10]ITU-TRecommendationG.823:"Thecontrolofjitterandwanderwithindigitalnetworkswhicharebasedonthe2048kbit/shierarchy".[11]ITU-TRecommendationO.172:"JitterandwandermeasuringequipmentfordigitalsystemswhicharebasedontheSynchronousDigitalHierarchy(SDH)".3Definitionsandabbreviations3.1DefinitionsForthepurposesofthepresentdocument,thetermsanddefinitionsgiveninEN300462-1-1[2]apply.3.2AbbreviationsForthepurposesofthepresentdocument,thefollowingabbreviationsapply:BSBaseStationBSCBaseStationControllerGSMGlobalSystemforMobilecommunicationsITU-TInternationalTelecommunicationsUnion-TelecommunicationsStandardizationSectorMSCMobileSwitchingCentreMTIEMaximumTimeIntervalErrorNENetworkElementPDHPlesiochronousDigitalHierarchyppmpartspermillionPSTNPublicSwitchedTelephoneNetworkSASEStandAloneSynchronizationEquipmentSDHSynchronousDigitalHierarchySSUSynchronizationSupplyUnitSSU-LSSULocalSTM-1optOpticalSTM-1interfaceSTM-1elElectricalSTM-1interfaceSIST EN 300 462-7-1 V1.1.2:2003

ETSIETSIEN300462-7-1V1.1.2(2001-06)7STM-NSynchronousTransportModule-NTDEVTimeDEViationUIUnitIntervalUIppUnitIntervalpeaktopeakAfulllistofabbreviationsusedintimingandsynchronizationislistedinEN300462-1-1[2].4FrequencyaccuracyThelong-termfrequencyaccuracynormallyapplieswhenoperatinginlongtermfreerunningconditions.SincetheSSU-Lisaslaveclock,thenthenormaloperatingmodesareeitherlockedorholdover.Thefrequencyaccuracyspecificationinholdovermodeisspecifiedinclause9.5Pull-inandpull-outrangesTheminimumpull-inrangeshallbe±0,5ppm,whatevertheinternaloscillatorfrequencyoffsetmaybe.Thepull-outrangeisforfurtherstudy.6NoisegenerationThenoisegenerationofanSSU-Lrepresentstheamountofphasenoiseproducedattheoutputwhenthereisanidealinputreferencesignalortheclockisinholdoverstate.Asuitablereference,forpracticaltestingpurposes,impliesaperformancelevelatleast10timesmorestablethantheoutputrequirements.Theabilityoftheclocktolimitthisnoiseisdescribedbyitsfrequencystability.ThemeasuresMTIEandT
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