1 Scope
2 Conformance
3 References
4 Definitions
   4.1 Basic call
   4.2 Incoming call
   4.3 Outgoing call
   4.4 User and network
5 Acronyms
6 General principles
   6.1 Protocol model
   6.2 Services provided to call control
   6.3 Services required of the Data Link Layer
       6.3.1 Acknowledged information transfer services
       6.3.2 Unacknowledged information transfer services
   6.4 Protocol control states
       6.4.1 States for circuit mode call control
       6.4.2 States for layer management
   6.5 Message segmentation and reassembly functions
       6.5.1 Null (0)
       6.5.2 Receiving segmented message (1)
7 General procedures
   7.1 Use of the services of Layer 2
   7.2 Message segmentation procedures
   7.3 Handling of protocol error conditions
       7.3.1 Addition to requirements of subclause 5.8.6.1 of
             ETS 300 102-1
       7.3.2 Addition to requirements of subclause 5.8.6.2 of
             ETS 300 102-1
       7.3.3 Modification to subclause 5.8.7.1, second paragraph,
             of ETS 300 102-1
       7.3.4 Replacement for items a, b and c of subclause
             5.8.7.1 of ETS 300 102-1
       7.3.5 Addition to requirements of subclause 5.8.7.2 of
             ETS 300 102-1
       7.3.6 Modification to subclause 5.8.7.2, first paragraph,
             of ETS 300 102-1
       7.3.7 Modification to subclause 5.8.7.2, second paragraph,
             of ETS 300 102-1
   7.4 Handling of configuration errors
   7.5 Status and status enquiry procedures
       7.5.1 Modifications to subclause 5.8.10 of ETS 300 102-1
       7.5.2 Modifications to subclause 5.8.11 of ETS 300 102-1
8 Procedures for circuit mode call control
   8.1 Call establishment at the originating interface
       8.1.1 Addition to subclause 5.1.1 of ETS 300 102-1
       8.1.2 Modification to the "ETSI requirement" concerning
             en-bloc sending in subclause 5.1.1 of ETS 300 102-1
       8.1.3 Modification to the "ETSI requirement" concerning the
             tone option in subclause 5.1.3 of ETS 300 102-1
       8.1.4 Clarification of subclause 5.1.5 of ETS 300 102-1
       8.1.5 Modification to subclause 5.1.6 of ETS 300 102-1
       8.1.6 Modification to the "ETSI requirement" concerning the
             sending of the alerting message in subclause 5.1.7 of
             ETS 300 102-1
       8.1.7 Modification to the "ETSI requirement" concerning the
             receipt of the alerting message in subclause 5.1.7 of
             ETS 300 102-1
       8.1.8 Addition to subclause 5.1.8 of ETS 300 102-1
       8.1.9 Non-applicability of transit network selection
   8.2 Call establishment at the destination interface
       8.2.1 Addition to subclause 5.2.1 of ETS 300 102-1
       8.2.2 Change to case 4 of subclause 5.2.3.1 of ETS 300 102-1
       8.2.3 Change to case b of subclause 5.2.3.2 of ETS 300 102-1
       8.2.4 Non-applicability of overlap receiving procedure
       8.2.5 Replacement of the first paragraph of 5.2.5.2 of ETS
             300 102-1
       8.2.6 Modification to the "ETSI requirement" concerning
             progress description value No. 1
       8.2.7 Addition to subclause 5.2.8 of ETS 300 102-1
   8.3 Call clearing
       8.3.1 Replacement of item b of subclause 5.3.2 of ETS 300
             102-1
       8.3.2 Non-applicability of item c of subclause 5.3.2 of
             ETS 300 102-1
       8.3.3 Modification to subclause 5.3.3 of ETS 300 102-1
       8.3.4 Modification to subclause 5.3.4.1 of ETS 300 102-1
       8.3.5 Modification to subclause 5.3.4.2 of ETS 300 102-1
   8.4 In-band tones and announcements
   8.5 Call collisions
   8.6 Suspend and resume procedures
   8.7 TE-side and PTN-side SDL diagrams
9 Procedures for layer management
   9.1 Restart procedures
10 List of system parameters
11 Functional definition and content of messages
   11.1 Messages for general procedures
        11.1.1 STATUS
        11.1.2 STATUS ENQUIRY
   11.2 Messages for circuit mode call control
        11.2.1 ALERTING
        11.2.2 CALL PROCEEDING
        11.2.3 CONNECT
        11.2.4 CONNECT ACKNOWLEDGE
        11.2.5 DISCONNECT
        11.2.6 INFORMATION
        11.2.7 PROGRESS
        11.2.8 RELEASE
        11.2.9 RELEASE COMPLETE
        11.2.10 RESUME
        11.2.11 RESUME ACKNOWLEDGE
        11.2.12 RESUME REJECT
        11.2.13 SETUP
        11.2.14 SETUP ACKNOWLEDGE
        11.2.15 SUSPEND
        11.2.16 SUSPEND ACKNOWLEDGE
        11.2.17 SUSPEND REJECT
        11.3 Messages for layer management
        11.3.1 RESTART
        11.3.2 RESTART ACKNOWLEDGE
12 General message format and coding of information elements
   12.1 Overview
   12.2 Protocol discriminator
   12.3 Call reference
   12.4 Message type
   12.5 Other information elements (Codeset 0)
        12.5.1 Coding rules
        12.5.2 Extensions of codesets
        12.5.3 Locking shift procedure
        12.5.4 Non-locking shift procedure
        12.5.5 Bearer capability
        12.5.6 Call identity
        12.5.7 Call state
        12.5.8 Called party number
        12.5.9 Called party subaddress
        12.5.10 Calling party number
        12.5.11 Calling party subaddress
        12.5.12 Cause
        12.5.13 Channel identification
        12.5.14 Connected number
        12.5.15 Connected subaddress
        12.5.16 Date/time
        12.5.17 Display
        12.5.18 High layer compatibility (Layers 4 - 7)
        12.5.19 Low layer compatibility (Layers 1 - 3)
        12.5.20 Progress indicator
        12.5.21 Restart indicator
        12.5.22 Segmented message
        12.5.23 Sending complete
   12.6 Information elements of codeset 5
        12.6.1 Party category
Annex A (informative) Use of progress indicators
Annex B (informative) Use of cause values
Annex C (informative) Examples of message sequences
Annex D (informative) Manufacturer-specific information
Annex E (informative) Bibliography
Annex F (informative) Terminal interchangeability
Annex G (normative) Protocol Implementation Conformance Statement
                      (PICS) Proforma