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• CCITT Rec. T.70 (11/1988) – NETWORK–INDEPENDENT BASIC TRANSPORT SERVICE FOR THE TELEMATIC SERVICES
• 1 Scope
• 2 Transport service
  • 2.1 Transport service objectives
  • 2.2 General structure of the transport service
• 3 Transport service implementation for different types of networks
  • 3.1 Terminals connected to a PSPDN
    • 3.1.1 Physical layer DTE/DCE interface characteristics
    • 3.1.2 Link layer procedure
    • 3.1.3 Network layer procedure
  • 3.2 Terminals connected to the PSTN
    • 3.2.1 Physical layer DTE/DCE interface characteristics
    • 3.2.2 Link layer procedure
    • 3.2.3 Network layer procedure
  • 3.3 Terminals connected to a CSPDN
    • 3.3.1 Physical layer DTE/DCE interface characteristics
    • 3.3.2 Link layer procedure
    • 3.3.3 Network layer procedure
  • 3.4 Terminals connected to an ISDN
• 4 Interworking between networks
• 5 Transport layer procedure
  • 5.1 Transport functions
    • 5.1.1 General
    • 5.1.2 Transport protocol classes
    • 5.1.3 The basic transport service (TS)
    • 5.1.4 Transport layer functions
  • 5.2 Description of connection establishment and termination procedures
    • 5.2.1 General
    • 5.2.2 Transport connection request (TCR) block
    • 5.2.3 Transport connection accept (TCA) block
    • 5.2.4 Transport connection clear (TCC) block
    • 5.2.5 Transport connection collision
    • 5.2.6 Extended addressing
  • 5.3 Description ofdata transfer procedures
    • 5.3.1 General
    • 5.3.2 Transport data block (TDT) length
    • 5.3.3 Transport service data unit (TSDU) end
  • 5.4 Treatment of procedure errors
  • 5.5 Formats
    • 5.5.1 General
    • 5.5.2 Structure of transport control and transport data blocks
    • 5.5.3 Concatenation
    • 5.5.4 Transport connection request (TCR) block format
    • 5.5.5 Transport connection accept (TCA) block format
    • 5.5.6 Transport connection clear (TCC) block format
    • 5.5.7 Transport block reject (TBR) block format
    • 5.5.8 Transport data block (TDT) format
• ANNEX A
• A.1 Transport and network service
• A.2 State transition diagrams for the basic transport layer procedures
• ANNEX B
• B.1 State tables
• B.2 Lists of events, actions and conditions
• ANNEX C – Recommendations for implementation of Recommendation X.21
• C.1 General
• C.2 Receipt of call progress signals 01 or 04
• C.3 Receipt of call progress signal 03
• C.4 Receipt of call progress signals of the group 2 to 8
• ANNEX D – Service definitions and state transition diagrams for the HDLC procedure and the network layer defined for CSPDN
• D.1 Service definitions
• D.2 State transition diagrams HDLC
• D.3 Summary of frame definitions
• D.4 X.21 service, controlled by the network layer