SIST EN 300 392-3-3 V1.2.1:2006

• Abstract:

  The present document defines the Terrestrial Trunked Radio system (TETRA) supporting Voice plus Data (V+D). It specifies:; • general design aspects (e.g. reference points, numbering and addressing, or protocol architecture);; • the interworking between TETRA networks;; • the interworking of TETRA networks with other networks, via gateways;; • the supplementary services applicable to the basic TETRA tele- or bearer services.; The TETRA V+D interworking - basic operation part defines the interworking between TETRA networks over the corresponding interface: the Inter-System Interface (ISI). It comprises the following sub-parts:; • ISI general design;; • Additional Network Feature - ISI Individual Call (ANF-ISIIC);; • Additional Network Feature - ISI Group Call (ANF-ISIGC);; • Additional Network Feature - ISI Short Data service (ANF-ISISD);; • Additional Network Feature - ISI Mobility Management (ANF-ISIMM);; • Speech Format Implementation for Circuit Mode Transmission;; • Speech Format Implementation for Packet Mode Transmission.; The present document is the ANF-ISIGC sub-part. In analogy with ITU-T Recommendation I.130 [19], the stage one, stage two and stage three of the three level structure is used to describe the TETRA Inter-System Interface services as provided by European Private or Public Trunked Radio System operators:; • Stage 1, is an overall service description, from the service subscriber's and user's standpoint;; • Stage 2, identifies the functional capabilities and information flows needed to support the services described in stage 1; and; NOTE: The information flows in stage 2 have been drawn as Message Sequence Charts (MSC). Therefore PISN basic call information flows are also shown together with the ANF-ISIGC information flows.; • Stage 3, defines the signalling system protocols and switching functions needed to implement the services described in stage 1.; The present document details the Interworking Basic Operation of the Terrestrial Trunked Radio system (TETRA). Specifically this sub-part details the stage 1 aspects (overall service description) of the ANF-ISIGC as seen from the TETRA Switching and Maintenance Infrastructure point of view at the Inter-System Interface (ISI). It details the stage 2 aspects (functional partitioning) of ANF-ISIGC which includes the identification of the functional entities and the flows between them, and finally it details the stage 3 signalling protocols for the ANF-ISIGC services, i.e. the protocols at the relevant reference points between the functional entities defined in stage 2.; The ANF-ISIGC service specifies:; • TETRA Group Call Clear Speech over the ISI, acknowledged and unacknowledged;; • TETRA Group Call End-to-End Encrypted Speech over the ISI;; • TETRA Group Call Circuit Mode one slot data over the ISI;; • TETRA Group Call Circuit Mode one slot End-to-End Encrypted data over the ISI;; • TETRA Group Call Circuit Mode N × 2,4 kbit/s, N × 4,8 kbit/s or N × 7,2 kbit/s data, with N = 2, 3 or 4;; • TETRA Group Call Circuit Mode N × 2,4 kbit/s N × 4,8 kbit/s or N × 7,2 kbit/s End-to-End Encrypted data, with N = 2, 3 or 4.

• Status: Published
• Publication Date: 31-Mar-2006
• ICS: 33.070.10 - Terrestrial Trunked Radio (TETRA)
• Technical Committee: SS EIT - Technical Board for the electrotechnical, information technology and telecommunications fields
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Apr-2006
• Due Date: 01-Apr-2006
• Completion Date: 01-Apr-2006
• Mandate: T-172
• Ref Project: ETSI EN 300 392-3-3 V1.2.1 (2004-01) - Terrestrial Trunked Radio (TETRA); Voice plus Data (V+D); Part 3: Interworking at the Inter-System Interface (ISI); Sub-part 3: Additional Network Feature Group Call (ANF-ISIGC)

Overview

SIST EN 300 392-3-3 V1.2.1:2006 is a Slovenian standard that defines crucial elements of the Terrestrial Trunked Radio (TETRA) system, focusing specifically on Voice plus Data (V+D) services. This document, aligning with the European Standard EN 300 392-3-3, details the Interworking at the Inter-System Interface (ISI), with particular emphasis on the Additional Network Feature – ISI Group Call (ANF-ISIGC).

The core purpose of this standard is to enable interoperability between different TETRA networks and between TETRA and external networks. It specifies reference points, addressing, and protocol architectures that support vital group call operations across interconnected TETRA infrastructures-ensuring seamless, secure, and reliable group communications for private and public trunked radio system operators.

Key Topics

• TETRA Interworking at ISI: Establishes architectures and protocols enabling multiple TETRA networks to connect and exchange group calls via the Inter-System Interface.
• ANF-ISIGC Service Specification: Describes procedures for establishing, maintaining, and terminating group calls across systems, including handling both clear and encrypted communication.
• Stage-Based Framework:
  • Stage 1: High-level description from the user and service provider perspective.
  • Stage 2: Functional capabilities and information flows, with sequence charts illustrating group call interactions.
  • Stage 3: Technical detailing of protocols and switching functions at the ISI.
• Types of Group Call Supported:
  • Clear speech and end-to-end encrypted group calls.
  • Circuit mode data transfer for group calls, both clear and encrypted.
  • Support for various TETRA data rates and slot configurations.
• Interworking and Supplementary Services: Covers compatibility and operation with supplementary telecommunication services such as call forwarding, caller ID, priority calling, call hold, and others.

Applications

The provisions in SIST EN 300 392-3-3 V1.2.1:2006 deliver substantial practical benefits in environments where robust, scalable, and interoperable group communications are essential. Key applications include:

• Public Safety and Emergency Services: Police, fire, ambulance, and public safety organizations rely on standardized group call interworking to maintain secure and reliable communications across jurisdictional or organizational TETRA networks.
• Transport and Utilities: Railways, airports, and utility services use TETRA’s group call features for real-time coordination and operations management across regional or national infrastructures.
• Commercial and Industrial Security: Large-scale commercial sites and critical infrastructure benefit from group call interworking for rapid incident response and operational messaging.
• Cross-Network Communication: The standard’s gateway provisions support interworking between TETRA systems and other networks, such as public switched telephone networks (PSTN), ISDN, or private integrated services networks (PISN), extending reach and functionality.

Related Standards

To establish comprehensive TETRA network interworking, SIST EN 300 392-3-3 V1.2.1:2006 should be consulted in conjunction with related standards, including:

• EN 300 392-2: Details TETRA voice plus data system architecture and network interfaces.
• Other EN 300 392-3 Series: Covers general ISI design, individual call (ANF-ISIIC), short data services (ANF-ISISD), and mobility management (ANF-ISIMM).
• ITU-T Recommendation I.130: Provides a reference model for telecommunication service specification stages.

By adhering to this standard, operators and vendors ensure that their TETRA solutions offer high levels of compatibility, security, and performance when supporting group calls over interconnected radio networks. This is vital for mission-critical environments where effective communication can significantly impact safety and operational efficiency.

SLOVENSKI STANDARD
01-april-2006
Prizemni snopovni radio (TETRA) - Govor in podatki (V+D) - 3. del: Medsebojno
delovanje na medsistemskem vmesniku (ISI) - 3. poddel: Dodatna omrežna
funkcija: skupinski klic (ANF-ISIGC)
Terrestrial Trunked Radio (TETRA); Voice plus Data (V+D); Part 3: Interworking at the
Inter-System Interface (ISI); Sub-part 3: Additional Network Feature Group Call (ANF-
ISIGC)
Ta slovenski standard je istoveten z: EN 300 392-3-3 Version 1.2.1
ICS:
33.070.10 Prizemni snopovni radio Terrestrial Trunked Radio
(TETRA) (TETRA)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

European Standard (Telecommunications series)

Terrestrial Trunked Radio (TETRA);
Voice plus Data (V+D);
Part 3: Interworking at the Inter-System Interface (ISI);
Sub-part 3: Additional Network Feature
Group Call (ANF-ISIGC)
2 ETSI EN 300 392-3-3 V1.2.1 (2004-01)

Reference
REN/TETRA-03087
Keywords
interworking, radio, TETRA, V+D
ETSI
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ETSI
3 ETSI EN 300 392-3-3 V1.2.1 (2004-01)
Contents
Intellectual Property Rights.9
Foreword.9
1 Scope.11
2 References.12
3 Definitions and abbreviations.13
3.1 Definitions.13
3.2 Abbreviations.14
4 ANF-ISIGC stage 1 specification.15
4.1 Description.15
4.1.1 General description.15
4.1.2 Qualifications on applicability to TETRA basic services .15
4.2 Procedures.16
4.2.1 Provision/withdrawal.16
4.2.2 Normal procedures.16
4.2.2.1 Activation/deactivation/registration/interrogation.16
4.2.2.2 Invocation and operation.16
4.2.2.3 ANF-ISIGC - the service provider.16
4.2.2.3.1 Establishing the group call at the originating and controlling TETRA SwMI .17
4.2.2.3.2 Establishing the group call at a participating TETRA SwMI .18
4.2.2.3.3 Delaying the group call .20
4.2.2.3.4 Control of call time-out timers .20
4.2.2.3.5 Acknowledged group call procedures .21
4.2.2.3.6 Colliding calls.21
4.2.2.3.7 Maintenance of the group call .22
4.2.2.3.8 Termination of the group call .25
4.2.3 Exceptional procedures.25
4.2.3.1 Activation/deactivation/registration/interrogation.25
4.2.3.2 Invocation and operation.25
4.3 Interaction with other PISN supplementary services and PISN ANFs.26
4.4 Interaction with TETRA supplementary services and other TETRA ANFs .26
4.4.1 Calling Line Identification Presentation (SS-CLIP) .26
4.4.2 Connected Line Identification Presentation (SS-COLP) .26
4.4.3 Calling/Connected Line Identification Restriction (SS-CLIR).26
4.4.4 Call Report (SS-CR) .26
4.4.5 Talking Party Identification (SS-TPI).27
4.4.6 Call Forwarding Unconditional (SS-CFU) .27
4.4.7 Call Forwarding on Busy (SS-CFB) .27
4.4.8 Call Forwarding on No Reply (SS-CFNRy) .27
4.4.9 Call Forwarding on Not Reachable (SS-CFNRc) .27
4.4.10 List Search Call (SS-LSC).27
4.4.11 Call Authorized by Dispatcher (SS-CAD).27
4.4.12 Short Number Addressing (SS-SNA) .27
4.4.13 Area Selection (SS-AS) .27
4.4.14 Access Priority (SS-AP) .27
4.4.15 Priority Call (SS-PC) .28
4.4.16 Call Waiting (SS-CW).28
4.4.17 Call Hold (SS-HOLD) .28
4.4.18 Call Completion to Busy Subscriber (SS-CCBS) .28
4.4.19 Late Entry (SS-LE) .28
4.4.20 Transfer of Control (SS-ToC).28
4.4.21 Pre-emptive Priority Call (SS-PPC).28
4.4.22 Include Call (SS-IC) .29
4.4.23 Advice of Charge (SS-AoC) .29
4.4.24 Barring of Outgoing Calls (SS-BOC) .29
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4 ETSI EN 300 392-3-3 V1.2.1 (2004-01)
4.4.25 Barring of Incoming Calls (SS-BIC) .29
4.4.26 Discreet Listening (SS-DL) .29
4.4.27 Ambience Listening (SS-AL) .29
4.4.28 Dynamic Group Number Assignment (SS-DGNA).29
4.4.29 Call Completion on No Reply (SS-CCNR) .29
4.4.30 Call Retention (SS-CRT).29
4.4.31 Additional Network Features - Inter-System Interface Individual Call (ANF-ISIIC) .30
4.4.32 ISI Short Data (ANF-ISISD) .30
4.4.33 ISI Mobility Management (ANF-ISIMM).30
4.5 Interworking considerations.30
4.6 Static description of ANF-ISIIC using attributes .31
4.7 Overall SDL.33
5 ANF-ISIGC stage 2 specification.45
5.1 Functional model.45
5.1.1 Functional model description.45
5.1.2 Description of functional entities.46
5.1.2.1 ISI group call originating entity, FE1.46
5.1.2.2 Originating SwMI CC application functional entity, FE1'.47
5.1.2.3 ISI group call controlling entity, FE2.47
5.1.2.4 Controlling SwMI CC application functional entity, FE2'.48
5.1.2.5 ISI group call participating entity, FE3.48
5.1.2.6 Participating SwMI CC application functional entity, FE3'.49
5.1.2.7 ISI Calling MS Database entity (ITSI), FE4 .49
5.1.2.8 ISI Called Group Database entity (GTSI), FE5.49
5.1.3 Relationship of functional model to PSS1 basic call functional model .50
5.2 Information flow.50
5.2.1 Information flow diagrams.50
5.2.1.1 Successful group call set-up over ISI using ANF-ISIGC.51
5.2.1.2 Acknowledged group call set-up over ISI using ANF-ISIGC.63
5.2.1.3 Partial group call set-up over ISI using ANF-ISIGC .64
5.2.1.4 Delay of group call set-up over ISI using ANF-ISIGC.67
5.2.1.5 Interaction with an active group call .71
5.2.1.6 Unsuccessful group call set-up over ISI using ANF-ISIGC.73
5.2.1.7 Call Maintenance procedures - Request to transmit.78
5.2.1.8 Call maintenance procedures - Cease transmission.87
5.2.1.9 Call Maintenance procedures - Withdraw/Continue from an active group call .91
5.2.1.10 Call Maintenance procedures - Information flow to participating SwMI(s) .93
5.2.1.11 Call Maintenance procedures - Group call restoration over ISI using ANF-ISIGC.93
5.2.1.12 Call Disconnection procedures - Controlling SwMI disconnects the call .100
5.2.1.13 Call Disconnection procedures - Participating SwMI disconnects from the call .101
5.2.1.14 Call Disconnection procedures - Call Owner disconnects the whole call .103
5.2.2 Definitions of information flows .104
5.2.2.1 ISI_CALL RESTORATION.104
5.2.2.2 ISI_CALL RESTORATION Reject.105
5.2.2.3 ISI_CONNECT.106
5.2.2.4 ISI_DISCONNECT.106
5.2.2.5 ISI_ORIGINATING SETUP .107
5.2.2.6 ISI_INFO .107
5.2.2.7 ISI_INTERACT.108
5.2.2.8 ISI_POLL.109
5.2.2.9 ISI_REJECT.109
5.2.2.10 ISI_RELEASE .110
5.2.2.11 ISI_REROUTE .110
5.2.2.12 ISI_RESOURCE.111
5.2.2.13 ISI_SETUP.111
5.2.2.14 ISI_TX-CEASED.112
5.2.2.15 ISI_TX-CONTINUE.112
5.2.2.16 ISI_TX-DEMAND.113
5.2.2.17 ISI_TX-GRANTED.113
5.2.2.18 ISI_TX-INTERRUPT .114
5.2.2.19 ISI_TX-WAIT.114
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5 ETSI EN 300 392-3-3 V1.2.1 (2004-01)
5.2.2.20 VERIFY_GROUP.114
5.2.2.21 VERIFY_INDIV.115
5.3 Functional Entity Actions (FEAs) .115
5.3.1 FEA of FE1.115
5.3.2 FEA of FE1' .116
5.3.3 FEA of FE2.116
5.3.4 Functional entity actions of FE2' .120
5.3.5 FEA of FE3.120
5.3.6 Functional entity actions of FE3' .122
5.3.7 Functional entity actions of FE4 .123
5.3.8 Functional entity actions of FE5 .124
6 ANF-ISIGC stage 3 specification.124
6.1 ANF-ISIGC description.124
6.2 ANF-ISIGC operational requirements.124
6.2.1 PISN connection oriented call related connection .124
6.2.1.1 Requirements on the originating SwMI .124
6.2.1.1.1 PSS1 SETUP message.124
6.2.1.2 Requirements on the group home SwMI.125
6.2.1.2.1 PSS1 DISCONNECT or PSS1 RELEASE COMPLETE message .125
6.2.1.3 Requirements on the controlling SwMI .125
6.2.1.3.1 PSS1 DISCONNECT or PSS1 RELEASE COMPLETE message .125
6.2.1.3.2 PSS1 SETUP message.125
6.2.1.3.3 PSS1 CONNECT message.126
6.2.1.4 Requirements on the participating SwMI.127
6.2.1.4.1 PSS1 DISCONNECT or PSS1 RELEASE COMPLETE message .127
6.2.1.4.2 PSS1 CONNECT message.127
6.2.1.5 Requirements on the originating SwMI with PSTN/ISDN/PISN incoming gateway .127
6.2.1.5.1 PSS1 SETUP message.127
6.2.2 PISN connection oriented, call independent connection.128
6.3 ANF-ISIGC coding requirements.129
6.3.1 TETRA ANF-ISIGC PDUs.129
6.3.1.1 PISN connection oriented call related connection.130
6.3.1.1.1 TETRA PDU giving complementary information in the PSS1 SETUP, PSS1 CONNECT or
PSS1 FACILITY message.130
6.3.1.1.2 TETRA PDU giving complementary information in the PSS1 CONNECT or
PSS1 FACILITY message.134
6.3.1.1.3 TETRA PDU giving complementary information in the PSS1 FACILITY message.136
6.3.1.1.4 TETRA PDU giving complementary information in the PSS1 DISCONNECT or PSS1
FACILITY message .144
6.3.1.1.5 TETRA PDU giving complementary information in the PSS1 DISCONNECT, PSS1
FACILITY or PSS1 RELEASE message .145
6.3.1.1.6 TETRA PDU giving complementary information in the PSS1 DISCONNECT or PSS1
RELEASE COMPLETE message .146
6.3.1.2 PISN connection oriented, call independent connections .147
6.3.1.2.1 TETRA PDU sent by the participating SwMI of the migrated user - used to initiate call
restoration.147
6.3.1.2.2 TETRA PDU sent by the controlling SwMI - used to confirm call restoration.148
6.3.1.2.3 TETRA PDU sent by the controlling SwMI - used to reject call restoration .148
6.3.2 TETRA PDU information element coding .148
6.3.2.1 Additional information to existing information element at the ISI .149
6.3.2.1.1 Call status.149
6.3.2.1.1a Call time-out, set-up phase .149
6.3.2.1.2 Call time-out.149
6.3.2.1.3 Disconnect cause information element.150
6.3.2.1.4 Temporary group basic migration profile.150
6.3.2.1.5 PDU type.151
6.3.2.1.6 SS-migration profile.151
6.3.2.2 New information elements used at the ISI .152
6.3.2.2.1 Call amalgamation.152
6.3.2.2.1a Call resource time-out .152
6.3.2.2.2 Call diverted to dispatcher.152
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6 ETSI EN 300 392-3-3 V1.2.1 (2004-01)
6.3.2.2.3 Call owner request.152
6.3.2.2.4 Calling group identifier.153
6.3.2.2.5 Connected party SSI and extension .153
6.3.2.2.6 Controlling/originating/participating SwMI MNI .153
6.3.2.2.7 Critical connected party/requesting party/restoring party/transmitting party SSI and extension.153
6.3.2.2.8 Critical user list.153
6.3.2.2.9 Disconnect type.153
6.3.2.2.10 Dispatcher acceptance.154
6.3.2.2.11 External group member identity.154
6.3.2.2.12 External subscriber number digits .154
6.3.2.2.13 External subscriber number length .155
6.3.2.2.14 External subscriber number parameter .155
6.3.2.2.15 Fail Cause.155
6.3.2.2.16 Group attachment indicator .156
6.3.2.2.16a Group call SwMI type .156
6.3.2.2.17 Group information.156
6.3.2.2.17a ISI-INFO type.156
6.3.2.2.17b Linking group identifier.157
6.3.2.2.18 New calling party .157
6.3.2.2.19 Numbering plan identifier .158
6.3.2.2.20 Poll request type .158
6.3.2.2.21 Poll result identifier .158
6.3.2.2.22 Reject cause information element.159
6.3.2.2.23 Resource allocation.159
6.3.2.2.24 Resource indicator.159
6.3.2.2.25 Screening indicator.160
6.3.2.2.26 Security level at air interface/Security level used in other network.160
6.3.2.2.27 Set-up type.160
6.3.2.2.28 Speech service chosen/requested/used .160
6.3.2.2.29 Speech services supported.160
6.3.2.2.30 SS-CLIR invoked for calling/transmitting/restoring/connected party .161
6.3.2.2.31 Temporary group member indication .161
6.3.2.2.32 Transmission Ceased.161
6.3.2.2.33 Type of number .162
6.3.3 PSS1 facility information element .162
6.4 ANF-ISIGC state definitions.163
6.4.1 States at the originating SwMI.163
6.4.1.1 IDLE.163
6.4.1.2 FORWARD CALL.163
6.4.1.3 WAIT CONNECT.163
6.4.1.4 DELAY ENTRY.164
6.4.1.5 DELAY GROUP CALL .164
6.4.1.6 CALL DISCONNECT.164
6.4.1.7 CALL RELEASE.165
6.4.2 States at the controlling SwMI.165
6.4.2.1 IDLE.165
6.4.2.2 GROUP CALL INITIATE.165
6.4.2.3 DELAY GROUP CALL .166
6.4.2.4 ACTIVE.166
6.4.2.5 Void.167
6.4.2.6 CALL RELEASE.167
6.4.3 States at the participating SwMI.167
6.4.3.1 IDLE.167
6.4.3.2 WAIT CONNECT.168
6.4.3.3 DELAY ENTRY.168
6.4.3.4 DELAY GROUP CALL .168
6.4.3.5 ACTIVE.169
6.4.3.6 CALL DISCONNECT.169
6.4.3.7 CALL RELEASE.169
6.5 ANF-ISIGC signalling procedures .170
6.5.1 Call set-up procedures .170
6.5.1.1 Forward set-up request and PISN called number sending.170
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7 ETSI EN 300 392-3-3 V1.2.1 (2004-01)
6.5.1.2 Group linking.170
6.5.1.3 Call request, information channel selection and PISN called number sending .170
6.5.1.4 Call confirmation and call characteristics notification by the originating and participating
SwMI(s) .171
6.5.1.5 Call confirmation indication and call connected by the controlling SwMI.172
6.5.1.6 Delay of call set-up .172
6.5.1.7 Failure of call establishment .173
6.5.1.8 Multiple calling parties .173
6.5.1.8.1 A new calling party appears at a SwMI not currently in the group call.173
6.5.1.8.2 A new, compatible, calling party appears at a SwMI where a group call is active.173
6.5.1.8.3 A new, compatible, calling party appears at an OSwMI where a group call is still in the setup
phase.173
6.5.1.8.4 A new, compatible, calling party appears at an PSwMI where a group call is still in the setup
phase.173
6.5.1.8.5 A new calling party requesting an emergency call appears at a SwMI where the existing call
is not at an emergency priority .174
6.5.1.8.6 A new, non compatible, calling party appears at a SwMI where a group call is already active .174
6.5.1.8.7 A new calling party appears at a CSwMI that only supports a single ISI-Originating-Setup.174
6.5.1.8.8 The sending of subsequent ISI-Originating-Setups to the CSwMI.174
6.5.2 Acknowledge group call .175
6.5.3 Call maintenance procedures.175
6.5.3.1 Transmission control procedures .175
6.5.3.2 Call modification and/or continuation.176
6.5.3.3 Call restoration.177
6.5.3.4 DTMF procedures.178
6.5.4 Call disconnection procedures .178
6.5.5 Call collisions.179
6.5.6 Mapping of PSS1 messages with ISI PDUs.179
6.6 ANF-ISIGC impact from interworking with ISDN/PISN/PSTN .180
6.6.1 Call set-up procedures .180
6.6.2 Call maintenance procedures.180
6.6.3 Call disconnection procedures .181
6.7 Protocol interaction between ANF-ISIGC and supplementary services and other ANFs .181
6.7.1 Call Forwarding Unconditional (SS-CFU) .181
6.7.2 Call Authorized by Dispatcher (SS-CAD).181
6.7.3 Area Selection (SS-AS) and selected area number .182
6.7.4 Priority Call (SS-PC) .182
6.7.5 Pre-emptive Priority Call (SS-PPC).182
6.7.6 Include Call (SS-IC) .182
6.7.7 Call Retention (SS-CRT).183
6.7.8 Interactions with other supplementary services .183
6.8 ANF-ISIGC parameter values (timers).183
Annex A (normative): Specification and Description Language (SDL) representation of
procedures.184
A.1 SDL representation of an ANF-ISIGC entity at FE1 .184
A.2 SDL
...