Table of Contents
1Scope
2References
3Termsanddefinitions
4Abbreviations
5Conventions
6Generalserviceaspects
7Referenceconfigurations
7.1ConfigurationwhenaccessingPSPDNservices
(CaseA)
7.2ConfigurationfortheISDNvirtualcircuitservice
(CaseB)
8Serviceaspects
8.1AccesstoPSPDNservices(CaseA)
8.1.1Servicecharacteristics
8.1.2Useraccesscapabilities
8.1.3Basicrules
8.1.4Notificationclasses
8.2AccesstotheISDNvirtualcircuitservice(CaseB)
8.2.1Servicecharacteristics
8.2.2Useraccesscapabilities
8.2.3NotificationclassesforX.25incomingcalls
8.3Compatibilitychecking
9Addressingandroutingaspects
9.1Terminalinterfaceselection
9.1.1Terminalinterfaceselectionbymeans
ofMSDN/DDI
9.1.2Terminalinterfaceselectionbymeans
ofISDNsubaddressing
9.2AccesstoPSPDNservices(CaseA)
9.2.1Channeltypeselection
9.2.2Addressingschemeforoutgoingcalls
9.3AccesstotheISDNvirtualcircuitservice
(CaseB)
9.3.1Channeltypeselection
9.3.2Addressingschemeforoutgoingcalls
10Interworkingwithdedicatednetworks
10.1Circuit-modeaccesstoPSPDNservices(CaseA)
10.2AccesstoPSPDNsviavirtualcircuitservice
(CaseB)
11PacketcommunicationsattheS/T-referencepoint
11.1Outgoingaccess
11.1.1Circuit-switchedaccesstoPSPDNservices
(CaseA)
11.1.2AccesstotheISDNvirtualcircuitservice
(CaseB)
11.2Incomingaccess
11.2.1AccessfromPSPDNservice(CaseA)
11.2.2AccessfromtheISDNvirtualcircuitservice
(CaseB)
11.3X.25Virtualcallestablishmentandrelease
11.3.1Linklayerestablishmentandrelease
11.3.2Packetlayervirtualcallset-upandrelease
11.4Callclearing
11.4.1B-Channel
11.4.2D-Channel
11.4.3Additionalerrorhandlinginformation
11.4.4Causemappings
11.5Accesscollision
12Terminaladaptorfunctionalities
12.1General
12.2Physicalinterfaces
12.3AccessthroughtheB-channel
12.3.1General
12.3.2Rateadaption
12.3.3Signalling
12.3.4Synchronization
12.4AccessthroughtheD-channel
12.4.1General
12.4.2LAPB-LAPDmapping
12.4.3Signalling
12.5AccessthroughtheB-andD-channels
12.5.1General
12.5.2X.25outgoingcall
12.5.3X.25incomingcall
12.6Accessthroughthesemi-permanentH-channel
12.6.1General
12.6.2Rateadaption
12.6.3Signalling
12.7Testloops
12.7.1TestloopsforTAwithaccessthrough
theB-channel
12.7.2TestloopsforTAwithaccessthrough
theD-channel
AppendixI-B-channelTAactingonlayers2and3ofX.25
I.1Introduction
I.2Callcontrol
I.2.1Idlephase
I.2.2Establishmentphase
I.2.3Datatransferphase
I.2.4Clearingphase
AppendixII-InterconnectionofpacketmodeTE2swhichuse
thecircuit-modebearerserviceoftheISDN
AppendixIII-Examplemessageflowdiagramsandexample
conditionsforcausemapping
III.1Examplemessageflowdiagrams
III.1.1Keytothefigures
III.1.2Examplemessageflowdiagrams
III.2Exampleconditionsforcausemapping
AppendixIV-D-channelTAsrequiringfullprotocol
terminationTA
IV.1Introduction
IV.2Callcontrol
IV.2.1Idlephase
IV.2.2Establishmentphase
IV.2.3Datatransferphase
IV.2.4Clearingphase Abstract
Defines services available and signalling procedures operated at the S/T-reference point of an ISDN for subscribing packet mode terminal equipment, and terminal adaptor functionalities to support existing X.25 terminals at the R-reference point of the ISDN.