ETSI TS 123 283 V16.8.0 (2025-04)

LTE; Mission Critical Communication Interworking with Land Mobile Radio Systems (3GPP TS 23.283 version 16.8.0 Release 16)

RTS/TSGS-0623283vg80

General Information

• Status: Not Published
• Technical Committee: 3GPP SA 6 - Mission-critical applications
• Current Stage: 12 - Citation in the OJ (auto-insert)
• Completion Date: 03-Apr-2025

Standards Content (Sample)

TECHNICAL SPECIFICATION
LTE;
Mission Critical Communication Interworking
with Land Mobile Radio Systems
(3GPP TS 23.283 version 16.8.0 Release 16)

3GPP TS 23.283 version 16.8.0 Release 16 1 ETSI TS 123 283 V16.8.0 (2025-04)

Reference
RTS/TSGS-0623283vg80
Keywords
LTE
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3GPP TS 23.283 version 16.8.0 Release 16 2 ETSI TS 123 283 V16.8.0 (2025-04)
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ETSI
3GPP TS 23.283 version 16.8.0 Release 16 3 ETSI TS 123 283 V16.8.0 (2025-04)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 9
1 Scope . 10
2 References . 10
3 Definitions, symbols and abbreviations . 10
3.1 Definitions . 10
3.2 Abbreviations . 11
4 Introduction . 11
5 Assumptions and architectural requirements . 11
5.1 Key management . 11
5.2 Packet format . 12
6 Involved business relationships . 12
7 Functional model . 12
7.1 General . 12
7.2 Functional model description . 12
7.3 Functional entities description . 13
7.3.1 IWF . 13
7.4 Reference points . 13
7.4.1 Reference point IWF-1 (between the IWF and the MCPTT server) . 13
7.4.2 Reference point IWF-2 (between the IWF and the MCData server) . 13
7.4.3 Reference point IWF-3 (between the IWF and the group management server) . 14
8 Identities . 14
8.1 Identity mapping . 14
9 Application of functional model to deployments . 14
10 Procedures and information flows . 14
10.1 Affiliation . 14
10.1.1 Information flows for affiliation . 14
10.1.1.1 General . 14
10.1.1.2 IWF group affiliation request . 14
10.1.1.3 IWF group affiliation response . 15
10.1.1.4 IWF group de-affiliation request . 15
10.1.1.5 IWF group de-affiliation response . 15
10.1.2 Affiliation procedures . 16
10.1.2.1 General . 16
10.1.2.2 Group affiliation to a group defined in the MC system . 17
10.1.2.3 Group de-affiliation from a group defined in the MC system . 18
10.1.2.4 Group affiliation to group defined in the LMR system . 19
10.1.2.5 Group de-affiliation from a group defined in the LMR system . 20
10.2 Group management . 21
10.2.1 Information flows for group management . 21
10.2.1.1 General . 21
10.2.1.2 IWF group regroup teardown notification . 21
10.2.1.3 IWF group regroup teardown notification response . 21
10.2.1.4 IWF group regroup request . 21
10.2.1.5 IWF group regroup response . 21
10.2.1.6 IWF group regroup notification . 22
10.2.1.7 IWF group regroup notification response . 22
10.2.1.8 IWF group information request . 22
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10.2.1.9 IWF group information response . 22
10.2.1.10 IWF group information provision request . 23
10.2.1.11 IWF group information provision response . 23
10.2.1.12 IWF group information subscribe request . 23
10.2.1.13 IWF group information subscribe response . 23
10.2.1.14 IWF group information notify request . 24
10.2.1.15 IWF group information notify response . 24
10.2.2 Group regrouping . 24
10.2.2.1 General . 24
10.2.2.2 MC system initiates the group regroup . 24
10.2.2.3 IWF initiates the group regroup . 26
10.2.2.4 Ownership of the group regroup . 27
10.2.2.5 Simultaneous group regroup requests from each side of the IWF-1 interface . 27
10.2.2.6 Resolution of vocoder and encryption mode for the group regroup . 27
10.2.3 Group configuration for interworking. 27
10.2.3.1 Overview . 27
10.2.3.2 MC system provides group configuration to the IWF . 28
10.2.3.3 IWF requests group configuration from the MC system . 28
10.2.3.4 IWF provides group configuration to the MC system . 29
10.2.3.5 MC system requests group configuration from the IWF . 30
10.2.3.6 IWF subscribes to group configuration . 30
10.2.3.7 MC system notifies group configuration . 31
10.2.3.8 MC system subscribes to group configuration . 31
10.2.3.9 IWF notifies group configuration . 32
10.3 Group call . 33
10.3.1 General . 33
10.3.2 Information flows for group call over interworking group . 33
10.3.2.1 General . 33
10.3.2.2 IWF group call request . 33
10.3.2.3 IWF group call response (IWF – MCPTT server) . 33
10.3.2.4 IWF Group-broadcast group call setup request . 34
10.3.2.5 IWF Group-broadcast group call setup response . 34
10.3.2.6 IWF Group-broadcast group call release request . 34
10.3.2.7 IWF group-broadcast group call release response . 35
10.3.2.8 IWF group join request . 35
10.3.2.9 IWF group join response . 35
10.3.2.10 IWF group call leave request . 36
10.3.2.11 IWF group call leave response . 36
10.3.2.12 IWF group call release request . 36
10.3.2.13 IWF group call release response . 37
10.3.2.14 IWF pre-configured regroup request . 37
10.3.2.15 IWF pre-configured regroup response . 37
10.3.2.16 IWF pre-configured regroup cancel request . 37
10.3.2.17 IWF pre-configured regroup cancel response . 38
10.3.2.18 IWF pre-configured regroup reject (IWF – MCPTT server, MCPTT server - IWF) . 38
10.3.3 Pre-arranged group call . 38
10.3.3.1 General . 38
10.3.3.2 Group call setup initiated by MCPTT user on an interworking group defined in MCPTT system . 39
10.3.3.3 Group call setup initiated by LMR user on an interworking group defined in MCPTT system. . 40
10.3.3.4 Group call setup initiated by MCPTT user on an interworking group defined in the LMR system . 41
10.3.3.5 Group call setup initiated by LMR user on an interworking group defined in the LMR system. . 43
10.3.3.6 Encrypted group call with transcoding . 44
10.3.3.7 Late Entry . 46
10.3.3.7.1 General . 46
10.3.3.7.2 Group call late entry on an interworking group defined in the MCPTT system . 46
10.3.3.7.3 Group call late entry on an interworking group defined in the LMR system . 47
10.3.3.8 Interworking group call release . 49
10.3.3.8.1 General . 49
10.3.3.8.2 Group call release on an interworking group defined in the MCPTT system. 49
10.3.3.8.3 Group call release on an interworking group defined in the LMR system . 50
10.3.4 Group broadcast . 51
10.3.4.1 General . 51
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10.3.4.2 Group-broadcast group call procedure with an interworking group where the group-broadcast
group is defined in the MCPTT system. 51
10.3.4.3 Group-broadcast group call procedure with an interworking group where the group-broadcast
group is defined in the LMR system . 54
10.3.4.4 Group-broadcast group call release with an interworking group procedure where the group-
broadcast group is defined in the MCPTT system . 56
10.3.4.5 Group-broadcast group call release with an interworking group procedure where the group-
broadcast group is defined in the LMR system . 58
10.3.4.6 Broadcast group regroup call using pre-configured group . 59
10.3.4.6.1 General . 59
10.3.4.6.2 Broadcast group regroup call using pre-configured group the MCPTT system . 59
10.3.4.6.3 Broadcast group regroup call using pre-configured group in the IWF . 60
10.3.5 Chat group call . 61
10.3.5.1 General . 61
10.3.5.2 MCPTT user initiated chat group call in an interworking group defined in LMR system . 61
10.3.5.3 LMR user initiated chat group call in an interworking group defined in MCPTT system . 62
10.3.5.4 Release chat group call on an interworking group defined in the LMR system . 63
10.3.5.5 Release chat group call on an interworking group defined in the MCPTT system . 64
10.3.5.6 Void. 65
10.3.5.7 Void. 65
10.3.5.8 Newly joined MCPTT group member of a group defined in the LMR system . 65
10.3.5.9 Newly joined LMR group member of a group defined in the MCPTT system . 66
10.3.5.10 MCPTT client returning to coverage on a group homed in the LMR system . 67
10.3.6 Exiting group call due to de-affiliation . 68
10.3.6.1 General . 68
10.3.6.2 Exiting group call defined in the LMR system due to de-affiliation . 68
10.3.6.3 Exiting group call defined in the MCPTT system due to de-affiliation . 69
10.3.7 Group regroup with pre-configured group . 70
10.3.7.1 General . 70
10.3.7.2 Regroup formation using pre-configured group . 71
10.3.7.2.1 Regroup formation using pre-configured group initiated in the MCPTT system . 71
10.3.7.2.2 Regroup formation using pre-configured group initiated in the IWF . 73
10.3.7.3 Regroup cancellation using pre-configured group regroup . 74
10.3.7.3.1 Regroup cancellation using pre-configured group initiated in the MCPTT system . 74
10.3.7.3.2 Regroup cancellation using pre-configured group initiated in the IWF . 75
10.3.7.4 Regroup rejection using pre-configured group. 76
10.3.7.4.1 Regroup rejection using pre-configured group for regroup initiated in the MCPTT system . 76
10.3.7.4.2 Regroup rejection using pre-configured group for regroup initiated in the IWF . 77
10.3.7.5 Pre-configured regroup update procedures . 78
10.3.7.5.1 MCPTT client PTTs on MCPTT group during an in-progress pre-configured group regroup . 78
10.3.7.6 Call request on pre-configured regroup group after group regroup has been cancelled . 80
10.3.7.6.1 MCPTT client PTTs on pre-configured regroup group after group regroup has been cancelled . 80
10.3.7.7 Adding newly affiliated user to a pre-configured group regroup . 81
10.3.7.7.1 Adding newly affiliated MCPTT user to a pre-configured group regroup . 81
10.3.7.7.2 Adding newly affiliated user homed in the IWF to a pre-configured group regroup . 82
10.3.8 User regroup with pre-configured group . 82
10.3.8.1 General . 82
10.3.8.2 Pre-configured user regroup formation . 83
10.3.8.2.1 Pre-configured user regroup formation by the MCPTT system . 83
10.3.8.2.2 Pre-configured user grop regroup formation by the IWF . 85
10.3.8.3 Pre-configured user regroup cancellation . 86
10.3.8.3.1 Pre-configured user regroup cancellation by the MCPTT system . 86
10.3.8.3.2 Pre-configured user regroup cancellation by the IWF . 87
10.4 Private call . 87
10.4.1 Information flows for private calls . 87
10.4.1.1 General . 87
10.4.1.2 IWF private call request . 88
10.4.1.3 IWF private call response . 88
10.4.1.4 IWF ringing . 89
10.4.1.5 IWF call end request . 89
10.4.1.6 IWF call end response . 89
10.4.2 Private call setup in automatic commencement mode . 89
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10.4.2.1 MCPTT user initiating an MCPTT private call . 89
10.4.2.2 LMR user initiating a private call with MCPTT user . 91
10.4.3 Private call setup in manual commencement mode . 92
10.4.3.1 MCPTT user is initiating an MCPTT private call . 92
10.4.3.2 LMR user initiating a private call with MCPTT user . 94
10.4.4 Private call release . 96
10.4.4.1 MCPTT client initiated . 96
10.4.4.2 MCPTT server initiated . 97
10.4.4.3 LMR user initiated . 98
10.4.5 Encryption of private calls . 99
10.5 Floor control . 99
10.5.1 General . 99
10.5.2 Information flows for floor control . 99
10.5.2.1 General . 99
10.5.2.2 IWF floor request . 99
10.5.2.3 IWF floor granted . 100
10.5.2.4 IWF floor rejected . 100
10.5.2.5 IWF floor request cancel . 100
10.5.2.6 IWF floor request cancel response . 100
10.5.2.7 IWF floor request cancel notify . 101
10.5.2.8 IWF floor idle . 101
10.5.2.9 IWF floor release . 101
10.5.2.10 IWF floor taken . 102
10.5.2.11 IWF floor revoked . 102
10.5.2.12 IWF floor acknowledgement . 102
10.5.2.13 IWF queue position request. 102
10.5.2.14 IWF queue position info . 103
10.5.2.15 IWF unicast media stop request . 103
10.5.2.16 IWF unicast media resume request . 103
10.5.2.17 IWF floor talker ID update . 104
10.5.3 Interworking floor control . 104
10.5.4 Floor override without using floor revoked on an interworking group . 104
10.5.5 Floor control on an interworking group homed in the LMR system . 106
10.5.6 Floor control on an interworking group homed in the MCPTT system . 107
10.5.7 Floor control without local filtering on an interworking group defined in the LMR system . 108
10.5.8 Floor control without local filtering on an interworking group defined in the MCPTT system . 110
10.5.9 Floor control in private call controlled by the LMR system . 111
10.5.10 Floor control in private call controlled by the MCPTT system . 112
10.6 Emergency and imminent peril . 113
10.6.1 Information flows for emergency and imminent peril . 113
10.6.1.1 IWF emergency group call request . 113
10.6.1.2 IWF emergency group call response . 113
10.6.1.3 IWF imminent peril group call request . 114
10.6.1.4 IWF imminent peril group call response . 114
10.6.1.5 IWF in-progress imminent peril group state cancel request . 114
10.6.1.6 IWF in-progress imminent peril group state cancel response . 115
10.6.1.7 IWF emergency alert request . 115
10.6.1.8 IWF emergency alert response . 115
10.6.1.9 IWF emergency alert cancel request . 115
10.6.1.10 IWF emergency alert cancel response . 116
10.6.1.11 IWF in-progress emergency group state cancel request . 116
10.6.1.12 IWF in-progress emergency group state cancel response . 116
10.6.2 Emergency calls . 117
10.6.2.1 General . 117
10.6.2.2 Emergency group call . 117
10.6.2.2.1 Emergency group call setup initiated by a user in the LMR system on an interworking group
defined in the MCPTT system . 117
10.6.2.2.2 Emergency group call setup initiated by a user in the MCPTT system on an interworking
group defined in MCPTT system . 119
10.6.2.2.3 Emergency group call setup initiated by a user in the LMR system on an interworking group
defined in the LMR system . 121
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10.6.2.2.4 Emergency group call setup initiated by a user in the MCPTT system to an interworking
group defined in the LMR system . 122
10.6.2.3 In-progress emergency group state cancel of an interworking group . 124
10.6.2.3.1 LMR user initiated in-progress emergency group state cancel of an interworking group
defined in the MCPTT system . 124
10.6.2.3.2 MCPTT user initiated in-progress emergency group state cancel of an interworking group
defined in the MCPTT system . 125
10.6.2.3.3 LMR user initiated in-progress emergency group state cancel of an interworking group

defined in an LMR system. 126
10.6.2.3.4 MCPTT user initiated in-progress emergency group state cancel of an interworking group
defined in an LMR system. 127
10.6.2.4 Losing audio . 129
10.6.2.5 Default emergency group . 129
10.6.2.6 Emergency private call . 129
10.6.2.7 LMR systems that do not track group emergencies . 129
10.6.3 Imminent peril calls . 129
10.6.3.1 General . 129
10.6.3.2 Imminent peril group call initiated by an MCPTT user on an interworking group . 129
10.6.3.3 Group call initiated by a user in the LMR system on an interworking group in imminent peril
state . 131
10.6.3.4 In-progress imminent peril state cancel on an interworking group . 133
10.6.4 Emergency alerts . 135
10.6.4.1 Emergency alert initiated by LMR user . 135
10.6.4.2 Emergency alert initiated by MC service user . 136
10.6.5 Emergency alert cancellation . 138
10.6.5.1 Emergency alert cancellation of an LMR user . 138
10.6.5.2 Emergency alert cancellation of an MC servic
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