CCITT Rec. T.90 (11/1988) – CHARACTERISTICS AND PROTOCOLS FOR TERMINALS FOR TELEMATIC SERVICES IN ISDN
CONTENTS
1 Scope
1.1 General
1.2 Use of bearer capability
1.3 Protocol architecture
2 ISDN circuit-switched mode (DTE-DTE communication)
2.1 Protocol set
2.2 Application rules for B-channel circuit-switched mode
2.2.1 Layer 1 physical layer interface characteristics
2.2.2 Connection control phase
2.2.3 Layer 2 information transfer phase
2.2.4 Layer 3 - connection control phase
2.2.5 Layer 3 - virtual connection control and information transfer
2.2.6 Layer 3 - packet size (NPDU block length)
3 ISDN packet switched mode (DTE-DCE communication)
3.1 Protocol set
3.2 Application rules for B-channel packet-switched mode
3.2.1 Layer 1 - physical layer interface characteristics
3.2.2 Layer 2 - link layer procedure
3.2.3 Layer 3 - network layer procedure
4 Provision of the OSI network service (OSI NS)
4.1 Rationale for considering the OSI NS
4.2 Architecture/available ISO Standards and CCITT Recommendations
4.3 Requirements for the OSI NS
4.3.1 Minimum requirements for the OSI NS
4.3.2 Minimum functionality when receiving a call from a system using the OSI NS
5 Additional X.25 optional user facilities
5.1 Categories of additional functionalities (see Note)
5.2 Functionalities
6 Interactions between the D-channel and B-channel
7 Supplementary services
8 Terminal response time
9 Synchronization
10 Higher layer protocols
10.1 Transport layer
ANNEX A – Procedures for connection establishment, connection release and information transfer
A.1 B–channel circuit–switched mode
A.2 Packet–switched mode
APPENDIX I – Consideration of incoming calls for facsimile terminals from networks without HLC provision
APPENDIX II – Optional usage of T.70 NL protocol
II.1 Information transfer phase
II.2 Information transfer phase
APPENDIX III – Service definitions and state transition diagrams for the data link layer within the B-channel (CS-mode)
III.1 Service definitions
III.2 State transition disgrams HDLC
III.3 Summary of frame definitions
APPENDIX IV – Possible model for telematic endsystems taking into account the D-channel/B-channel coordination function