Table of Contents
1Scope
2References
3Definitions
4Abbreviations
5Overviewofthisrecommendation
6Descriptionofsignalsandmessages
6.1Escapesignal(ES)
6.2Moderequest(MR)
6.3Capabilitiesrequest(CR)
6.4Modeselect(MS)
6.5Capabilitieslist(CL)
6.6Capabilitieslistrequest(CLR)
6.7Acknowledgemessage(ACK)
6.8Negativeacknowledgemessage(NAK)
7Structureofsignalsandmessages
7.1Signals
7.2Messages
8Informationfieldcodingformat
8.1General
8.2CodingformatforparametersintheIandSfields
8.3Identificationfield(I)
8.4Standardinformationfield(S)
8.5Non-standardinformationfield(NS)
8.6Informationfieldlength
9V.8bistransactions
9.1PermittedV.8bistransactions
9.2TransactionspermittedatanytimeonthePSTN
andonleasedpoint-to-pointcircuits
9.3Transactionspermittedonlyuponautomatic
answeringofaPSTNcall
9.4Useofescapesignals
9.5Useofthenegativeacknowledgemessage(NAK)
9.6Statetransitiondiagrams
9.7SuppressionofACK(1)afteranMSmessage
9.8Errorrecovery
9.9Proceduresforinitiatingamodemstart-upafter
aV.8bistransaction
9.10Messagesegmentation
10Operatingprocedures
10.1Operatingprocedureswhennotautomaticallyanswering
onthePSTNandonleasedpoint-to-pointcircuits
10.2Operatingproceduresuponautomaticansweringofa
callonthePSTN
11DTE-DCEinterface
AppendixI-RecommendationV.8bisinterface
I.1Introduction
I.2Basicfeaturesofthisrecommendation
I.3Selectionofadesiredcommunicationmode
I.4Identificationofcommonoperatingmodes
I.5Automaticselectionbetweenterminals
I.6User-friendlyswitchingfromtelephonytodata
I.7Conferencingapplications
I.8Interworkingconsiderations
I.9RelationshipbetweenrecommendationsV.8andV.8bis
AppendixII-ExamplesofV.8bistransactions
AppendixIII-Effectofechosuppressors
III.1Introduction
III.2Operationofechosuppressors
III.3Dualtonesignalbreakthroughofechosuppressors
III.4V.8bistransactions4,5and6
III.5Automaticansweringtogetherwithavoice
recordingdevice
III.6Optionalstatusofprovisions Abstract
Defines signals, messages and procedures for exchanging over the PSTN and on leased point-to-point telephone-type circuits, when the modes of operation of DCEs and DTEs communicating over the connection need to be automatically established and selected.
