Q.850

INTERNATIONALTELECOMMUNICATIONUNIONITU-TQ.850TELECOMMUNICATIONSTANDARDIZATIONSECTOROFITU(05/98)SERIESQ:SWITCHINGANDSIGNALLINGDigitalsubscriberSignallingSystemNo.1–GeneralUsageofcauseandlocationintheDigitalSubscriberSignallingSystemNo.1andtheSignallingSystemNo.7ISDNUserPartITU-TRecommendationQ.850(PreviouslyCCITTRecommendation)ITU-TQ-SERIESRECOMMENDATIONSSWITCHINGANDSIGNALLINGForfurtherdetails,pleaserefertoITU-TListofRecommendations.SIGNALLINGINTHEINTERNATIONALMANUALSERVICEQ.1–Q.3INTERNATIONALAUTOMATICANDSEMI-AUTOMATICWORKINGQ.4–Q.59FUNCTIONSANDINFORMATIONFLOWSFORSERVICESINTHEISDNQ.60–Q.99CLAUSESAPPLICABLETOITU-TSTANDARDSYSTEMSQ.100–Q.119SPECIFICATIONSOFSIGNALLINGSYSTEMSNo.4ANDNo.5Q.120–Q.249SPECIFICATIONSOFSIGNALLINGSYSTEMNo.6Q.250–Q.309SPECIFICATIONSOFSIGNALLINGSYSTEMR1Q.310–Q.399SPECIFICATIONSOFSIGNALLINGSYSTEMR2Q.400–Q.499DIGITALEXCHANGESQ.500–Q.599INTERWORKINGOFSIGNALLINGSYSTEMSQ.600–Q.699SPECIFICATIONSOFSIGNALLINGSYSTEMNo.7Q.700–Q.849DIGITALSUBSCRIBERSIGNALLINGSYSTEMNo.1Q.850–Q.999GeneralQ.850–Q.919PUBLICLANDMOBILENETWORKQ.1000–Q.1099INTERWORKINGWITHSATELLITEMOBILESYSTEMSQ.1100–Q.1199INTELLIGENTNETWORKQ.1200–Q.1999BROADBANDISDNQ.2000–Q.2999ITU-TRECOMMENDATIONQ.850USAGEOFCAUSEANDLOCATIONINTHEDIGITALSUBSCRIBERSIGNALLINGSYSTEMNo.1ANDTHESIGNALLINGSYSTEMNo.7ISDNUSERPARTSummaryThisRecommendationdefinestheformat,encodingandsemanticsofcauseinformationelements/parametersandtheusageofthelocationfield,intheDigitalSubscriberSignallingSystemNo.1andtheSignallingSystemNo.7ISDNUserPart.ManycausevaluesareapplicabletobothDSS1andSSNo.7ISUPandthisRecommendationspecifiestheuseofeachcausevalueinotherRecommendations.SourceITU-TRecommendationQ.850wasrevisedbyITU-TStudyGroup11(1997-2000)andwasapprovedundertheWTSCResolutionNo.1procedureonthe15thofMay1998.iiRecommendationQ.850(05/98)FOREWORDITU(InternationalTelecommunicationUnion)istheUnitedNationsSpecializedAgencyinthefieldoftelecommunications.TheITUTelecommunicationStandardizationSector(ITU-T)isapermanentorganoftheITU.TheITU-Tisresponsibleforstudyingtechnical,operatingandtariffquestionsandissuingRecommendationsonthemwithaviewtostandardizingtelecommunicationsonaworldwidebasis.TheWorldTelecommunicationStandardizationConference(WTSC),whichmeetseveryfouryears,establishesthetopicsforstudybytheITU-TStudyGroupswhich,intheirturn,produceRecommendationsonthesetopics.TheapprovalofRecommendationsbytheMembersoftheITU-TiscoveredbytheprocedurelaiddowninWTSCResolutionNo.1.InsomeareasofinformationtechnologywhichfallwithinITU-T’spurview,thenecessarystandardsarepreparedonacollaborativebasiswithISOandIEC.NOTEInthisRecommendation,theexpressionAdministrationisusedforconcisenesstoindicatebothatelecommunicationadministrationandarecognizedoperatingagency.INTELLECTUALPROPERTYRIGHTSTheITUdrawsattentiontothepossibilitythatthepracticeorimplementationofthisRecommendationmayinvolvetheuseofaclaimedIntellectualPropertyRight.TheITUtakesnopositionconcerningtheevidence,validityorapplicabilityofclaimedIntellectualPropertyRights,whetherassertedbyITUmembersorothersoutsideoftheRecommendationdevelopmentprocess.AsofthedateofapprovalofthisRecommendation,theITUhadnotreceivednoticeofintellectualproperty,protectedbypatents,whichmayberequiredtoimplementthisRecommendation.However,implementorsarecautionedthatthismaynotrepresentthelatestinformationandarethereforestronglyurgedtoconsulttheTSBpatentdatabase.ITU1998Allrightsreserved.Nopartofthispublicationmaybereproducedorutilizedinanyformorbyanymeans,electronicormechanical,includingphotocopyingandmicrofilm,withoutpermissioninwritingfromtheITU.RecommendationQ.850(05/98)iiiCONTENTSPage1Scope..........................................................................................................................12Cause..........................................................................................................................12.1Format........................................................................................................................12.2Codesusedinthesub-fieldoftheCause................................................................12.2.1Extensionindicator(ext.)..............................................................................12.2.2Codingstandard............................................................................................22.2.3Location.........................................................................................................22.2.4Recommendation..........................................................................................22.2.5Causevalue(onlyapplicableinthecontextofRecommendationsQ.763andQ.931).....................................................................................................32.2.6Diagnostics(onlyapplicableinthecontextofRecommendationsQ.763andQ.931).....................................................................................................112.2.7Causedefinitions...........................................................................................153Generalrulesforth