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• ITU-T Rec. X.75 (1988)
• 0 Introduction
  • 0.1 General
  • 0.2 Elements
  • 0.3 Basic system structure
• 1 Physical layer - Characteristics of the signalling terminal/physical circuit interface
• 2 Link layer procedures between signalling terminals
  • 2.1 Scope and field of application
  • 2.2 Frame structure
  • 2.3 Elements of procedures
  • 2.4 Description of the procedures
  • 2.5 Multilink procedures (MLP)
• 3 Packet layer procedures between signalling terminals
  • 3.1 Procedures for virtual call set-up and clearing
  • 3.2 Procedures for permanent virtual circuit service
  • 3.3 Procedure for data and interrupt transfer
  • 3.4 Procedures for flow control and for reset
  • 3.5 Procedure for restart
  • 3.6 Relationship between layers
• 4 Packet formats for virtual calls and permanent virtual circuits
  • 4.1 General
  • 4.2 Call set-up and clearing packets
  • 4.3 Data and interrupt packets
  • 4.4 Flow control and reset packets
  • 4.5 Restart packets
• 5 Procedures and formats for user facilities and network utilities
  • 5.1 Description of optional user facilities
  • 5.2 Formats for optional user facilities
  • 5.3 Procedures for network utilities
  • 5.4 Formats for network utilities
• ANNEX A – Definition of symbols for Annexes B, C and D
• A.1 General
• A.2 Symbol definition of the state diagrams
• A.3 Order definition of the state diagrams
• A.4 Symbol definition of the action tables
• ANNEX B – State diagrams for the packet layer interface between STEs for normal cases
• ANNEX C – Actions taken by the STE on receipt of packets in a given state of the packet layer X/Y interface
• ANNEX D – Actions taken by the STE on time-outs in the packet layer
• ANNEX E – Coding of network generated diagnostic fields in X.75 clear, reset and restart packets
• ANNEX F – Association of error conditions with cause and diagnostic codes
• APPENDIX I – Examples of multilink resetting procedures
• I.1 Introduction
• I.2 MLP reset initiated by a single STE
• I.3 MLP reset initiated by both STEs simultaneously