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• CCITT Rec. X.31 (11/1988) – SUPPORT OF PACKET MODE TERMINAL EQUIPMENT BY AN ISDN
• CONTENTS
• 1 General service aspects
• 2 Reference configurations
  • 2.1 Configuration when accessing PSPDN services (Case A)
  • 2.2 Configuration for the ISDN virtual circuit service (Case B)
• 3 Service aspects
  • 3.1 Access to PSPDN services (Case A)
  • 3.2 Access to the ISDN virtual circuit service (Case B)
  • 3.3 Compatibility checking
• 4 Addressing and routing aspects
  • 4.1 Terminal interface selection
  • 4.2 Access to PSPDN services (Case \A)
  • 4.3 Access to the ISDN virtual-circuit service (Case B)
• 5 Interworking with dedicated networks
  • 5.1 Circuit-mode access to PSPDN services (Case A)
  • 5.2 Access to PSPDNs via virtual circuit service (Case B)
• 6 Packet communications at the S/T reference point
  • 6.1 Outgoing access
  • 6.2 Incoming access
  • 6.3 Virtual call establishment and release
  • 6.4 Call clearing
  • 6.5 Access collision
• 7 TERMINAL ADAPTOR FUNCTIONALITIES
  • 7.1 General
  • 7.2 Physical interfaces
  • 7.3 Access through the B-channel
  • 7.4 Access through the D-channel
  • 7.5 Access through the B and D channel
  • 7.6 Test loops
• APPENDIX I – B-channel TA acting on layers 2 and 3 of X.25
• I.1 Introduction
• I.1 Call control
• APPENDIX II – Interconnection of packet mode TE2s which use the circuit-mode bearer service of the ISDN
• APPENDIX III – Example message flow diagrams and example conditions for cause mapping
• III.1 Example message flow diagrams
• III.2 Example conditions for cause mapping
• APPENDIX IV – D-channel TAs requiring full protocol terminal in the TA
• IV.1 Introduction
• IV.2 Call control
• APPENDIX V – References