ETSI TS 123 256 V17.9.0 (2025-04)

5G; Support of Uncrewed Aerial Systems (UAS) connectivity, identification and tracking; Stage 2 (3GPP TS 23.256 version 17.9.0 Release 17)

RTS/TSGS-0223256vh90

General Information

• Status: Not Published
• Technical Committee: 3GPP SA 2 - Architecture
• Current Stage: 12 - Citation in the OJ (auto-insert)
• Completion Date: 03-Apr-2025

Standards Content (Sample)

TECHNICAL SPECIFICATION
5G;
Support of Uncrewed Aerial Systems (UAS)
connectivity, identification and tracking;
Stage 2
(3GPP TS 23.256 version 17.9.0 Release 17)

3GPP TS 23.256 version 17.9.0 Release 17 1 ETSI TS 123 256 V17.9.0 (2025-04)

Reference
RTS/TSGS-0223256vh90
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ETSI
3GPP TS 23.256 version 17.9.0 Release 17 2 ETSI TS 123 256 V17.9.0 (2025-04)
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Modal verbs terminology
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3GPP TS 23.256 version 17.9.0 Release 17 3 ETSI TS 123 256 V17.9.0 (2025-04)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 5
1 Scope . 7
2 References . 7
3 Definitions and abbreviations . 7
3.1 Definitions . 7
3.2 Abbreviations . 9
4 Architecture model and concepts . 9
4.1 General concept . 9
4.2 Architectural reference model . 10
4.2.1 General . 10
4.2.2 Logical UAV Reference Architecture. 11
4.2.3 5GS Non-roaming Reference Architecture . 13
4.2.4 5GS Roaming Reference Architecture . 13
4.2.5 Service-based interfaces . 13
4.2.6 Reference points . 13
4.3 Functional entities . 14
4.3.1 General . 14
4.3.2 UAS NF . 14
4.3.3 UAV. 14
4.3.4 AMF. 14
4.3.5 SMF . 14
4.3.6 SMF+PGW-C . 15
4.4 High level function . 15
4.4.1 Service Operations . 15
4.4.1.1 NEF Services. 15
4.4.1.1.1 General . 15
4.4.1.1.2 Nnef_Authentication service . 15
4.4.1.2 AF Services . 16
4.4.1.2.1 General . 16
4.4.1.2.2 Naf_Authentication service . 16
4.4.1.3 AMF Services . 17
4.4.1.4 SMF Services . 17
4.4.1.5 UDM Services . 17
4.4.1.6 LMF Services . 17
4.4.1.7 GMLC Services . 17
4.4.1.8 UDR Services . 17
4.4.1.9 PCF Services . 18
4.4.2 USS Disco ver y . 18
4.4.3 CAA-Level UAV ID Assignment . 18
4.5 Identifiers . 19
4.5.1 General . 19
4.5.2 CAA-Level UAV Identity . 19
4.5.3 3GPP UAV ID . 19
5 Functional description and information flows . 19
5.1 Void . 19
5.2 UAV Authentication and Authorization . 20
5.2.1 UUAA Model . 20
5.2.2 UUAA at Registration in 5GS (UUAA-MM) . 20
5.2.2.1 General . 20
5.2.2.2 UUAA-MM Procedure . 23
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5.2.3 UUAA At PDN Connection/PDU Session Establishment (UUAA-SM) . 25
5.2.3.1 General . 25
5.2.3.2 USS UAV Authorization/Authentication (UUAA) during the PDU Session Establishment . 26
5.2.3.3 USS UAV Authorization/Authentication (UUAA) during default PDN connection at Attach . 28
5.2.3.4 USS UAV Authorization/Authentication (UUAA) using UE requested PDN connectivity
procedure . 30
5.2.4 UUAA Re-authentication and Re-authorization by USS/UTM . 31
5.2.4.1 UAV Re-authentication procedure in 5GS . 31
5.2.4.2 UAV Re-authentication procedure in EPS . 32
5.2.4.3 USS initiated UAV Re-authorization procedure in 5GS . 33
5.2.4.4 USS initiated UAV Re-authorization procedure in EPS . 34
5.2.5 Authorization for C2 . 35
5.2.5.1 General . 35
5.2.5.2 Procedure for C2 authorization in 5GS . 35
5.2.5.2.1 C2 Authorization request during UUAA-SM procedure in 5GS . 35
5.2.5.2.2 UE initiated PDU Session Modification for C2 Communication . 36
5.2.5.2.3 UE initiated PDU Session Establishment for C2 Communication . 37
5.2.5.3 Procedure for C2 authorization in EPS . 39
5.2.5.3.0 C2 Authorization request during UUAA-SM procedure in EPS . 39
5.2.5.3.1 UE requested PDN connectivity for C2 authorization . 40
5.2.5.3.2 UE requested bearer resource modification of an existing PDN connection for C2
authorization . 41
5.2.5.4 USS initiated C2 pairing policy configuration . 43
5.2.5.4.1 USS initiated C2 pairing policy configuration in 5GS . 43
5.2.5.4.2 USS initiated C2 pairing policy configuration in EPS. 44
5.2.6 Void . 45
5.2.7 UUAA Revocation by USS/UTM . 45
5.2.8 UAV Controller Replacement. 46
5.2.8.1 UAV controller replacement in 5GS . 46
5.2.8.2 UAV controller replacement in EPS . 47
5.2.9 Revocation of C2 Connectivity . 48
5.2.9.1 Revocation of C2 connectivity in 5GS . 48
5.2.9.2 Revocation of C2 connectivity in EPS . 49
5.3 UAV Tracking . 50
5.3.1 UAV Tracking Model . 50
5.3.1.1 UAV Location Reporting Mode . 51
5.3.1.2 UAV Presence Monitoring Mode . 51
5.3.1.3 List of Aerial UEs in a geographic area . 51
5.3.2 Procedure for UAV location reporting. 51
5.3.3 Procedure for UAV presence monitoring . 52
5.3.4 Procedure for obtaining list of Aerial UEs in a geographic area. 54
Annex A (informative): Change history . 56
History . 58

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3GPP TS 23.256 version 17.9.0 Release 17 5 ETSI TS 123 256 V17.9.0 (2025-04)
Foreword
This Technical Specification has been produced by the 3rd Generation Partnership Project (3GPP).
The contents of the present document are subject to continuing work within the TSG and may change following formal
TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an
identifying change of release date and an increase in version number as follows:
Version x.y.z
where:
x the first digit:
1 presented to TSG for information;
2 presented to TSG for approval;
3 or greater indicates TSG approved document under change control.
y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections,
updates, etc.
z the third digit is incremented when editorial only changes have been incorporated in the document.
In the present document, modal verbs have the following meanings:
shall indicates a mandatory requirement to do something
shall not indicates an interdiction (prohibition) to do something
The constructions "shall" and "shall not" are confined to the context of normative provisions, and do not appear in
Technical Reports.
The constructions "must" and "must not" are not used as substitutes for "shall" and "shall not". Their use is avoided
insofar as possible, and they are not used in a normative context except in a direct citation from an external, referenced,
non-3GPP document, or so as to maintain continuity of style when extending or modifying the provisions of such a
referenced document.
should indicates a recommendation to do something
should not indicates a recommendation not to do something
may indicates permission to do something
need not indicates permission not to do something
The construction "may not" is ambiguous and is not used in normative elements. The unambiguous constructions
"might not" or "shall not" are used instead, depending upon the meaning intended.
can indicates that something is possible
cannot indicates that something is impossible
The constructions "can" and "cannot" are not substitutes for "may" and "need not".
will indicates that something is certain or expected to happen as a result of action taken by an agency
the behaviour of which is outside the scope of the present document
will not indicates that something is certain or expected not to happen as a result of action taken by an
agency the behaviour of which is outside the scope of the present document
might indicates a likelihood that something will happen as a result of action taken by some agency the
behaviour of which is outside the scope of the present document
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might not indicates a likelihood that something will not happen as a result of action taken by some agency
the behaviour of which is outside the scope of the present document
In addition:
is (or any other verb in the indicative mood) indicates a statement of fact
is not (or any other negative verb in the indicative mood) indicates a statement of fact
The constructions "is" and "is not" do not indicate requirements.
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3GPP TS 23.256 version 17.9.0 Release 17 7 ETSI TS 123 256 V17.9.0 (2025-04)
1 Scope
The present document specifies architecture enhancements for supporting Uncrewed Aerial Systems (UAS)
connectivity, identification, and tracking, according to the use cases and service requirements defined in TS 22.125 [5].
The following functions are specified:
- UAV Identification, authentication and authorization.
- UAV tracking in the 3GPP system:
- this includes how the 3GPP system can provide support for UAV to ground identification (e.g. to authorized
third parties such as police devices).
- handling of unauthorized UAVs and revocation of authorization.
2 References
The following documents contain provisions which, through reference in this text, constitute provisions of the present
document.
- References are either specific (identified by date of publication, edition number, version number, etc.) or
non-specific.
- For a specific reference, subsequent revisions do not apply.
- For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including
a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same
Release as the present document.
[1] 3GPP TR 21.905: "Vocabulary for 3GPP Specifications".
[2] 3GPP TS 23.501: "System architecture for the 5G System (5GS)".
[3] 3GPP TS 23.502: "Procedures for the 5G System (5GS)".
[4] 3GPP TS 23.222: "Common API Framework for 3GPP Northbound APIs".
[5] 3GPP TS 22.125: "Unmanned Aerial System (UAS) support in 3GPP".
[6] 3GPP TS 23.401: "General Packet Radio Service (GPRS) enhancements for Evolved Universal
Terrestrial Radio Access Network (E-UTRAN) access".
[7] 3GPP TS 36.300: "Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal
Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2".
[8] 3GPP TS 23.273: "5G System (5GS) Location Services (LCS); Stage 2".
[9] 3GPP TS 23.503: "Policy and charging control framework for the 5G System (5GS); Stage 2".
[10] 3GPP TS 33.256: "Security aspects of Uncrewed Aerial Systems (UAS)".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the terms and definitions given in TR 21.905 [1] and the following apply. A
term defined in the present document takes precedence over the definition of the same term, if any, in TR 21.905 [1] or
TS 23.501 [2].
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3GPP UAV ID: Identifier assigned by the 3GPP system and used by external AF (e.g. USS) to identify the UAV. GPSI
is used as the 3GPP UAV ID.
Broadcast Remote ID: The capability of providing Remote Identification and Tracking over broadcast radio links.
NOTE 1: In the scope of this release, the radio link for Broadcast Remote ID is assumed to utilize radio
technologies outside the scope of 3GPP.
CAA (Civil Aviation Administration)-Level UAV Identity: a UAV identity assigned by USS/UTM, and uniquely
identifies a UAV at least within the scope of a USS.
Command and Control (C2) Communication: the user plane link to deliver messages with information of command
and control for UAV operation from a UAV controller or a UTM to a UAV or to report telemetry data from a UAV to
its UAV controller or a UTM.
C2 Aviation Payload: Contains application layer information sent by the UAS to the USS containing UAV pairing
information and/or flight authorization information that is transparent to the 3GPP System.
C2 Authorization Payload: Contains application layer information sent by the USS to the UAV containing e.g. C2
pairing information and/or C2 security information that is transparent to the 3GPP System.
C2 Pairing Information: Contains UAV-C Addressing Information which may e.g. include the UAV-C IP Address.
Networked UAV Controller: a UAV Controller connected to the 3GPP network and connected to the UAV via a
3GPP network.
Non-Networked UAV Controller: a UAV Controller not connected to the 3GPP network and connected to UAV via a
transport outside the scope of 3GPP, e.g. internet connectivity or direct wireless communication over a technology
outside the scope of 3GPP.
Networked Remote ID: The capability of providing Remote Identification and Tracking to a USS over 3GPP network.
Remote Identification (Remote ID) of UAS: The ability of a UAS in flight to provide identification and tracking
information that can be received by other parties, to facilitate advanced operations for the UAS (such as Beyond Visual
Line of Sight operations as well as operations over people), assist regulatory agencies, air traffic management agencies,
law enforcement, and security agencies when a UAS appears to be flying in an unsafe manner or where the UAS is not
allowed to fly. The Remote ID information payload may include Serial Number or Session ID assigned to the UAV,
location of the ground-station controller, emergency status indication, etc.
Third Party Authorized Entity: is either a privileged Networked UAV Controller, or a privileged Non-Networked
UAV Controller, or another entity which gets information on sets of UAV controllers and UAVs from the 3GPP
network, and may be connected to the UAV via the Internet; it may be authorized by the UTM to interface with sets of
UAV(s).
UAS NF: a 3GPP UAS Network Function for support of aerial functionality related to UAV identification,
authentication/authorization and tracking, and to support Remote Identification.
UAS Service Supplier (USS): An entity that provides services to support the safe and efficient use of airspace by
providing services to the operator / pilot of a UAS in meeting UTM operational requirements. A USS can provide any
subset of functionality to meet the provider's business objectives (e.g. UTM, Remote Identification). In the scope of this
specification, the term USS refers to both USS and USS/UTM.
UAS Traffic Management (UTM): a system that can safely and efficiently integrate the flying UAV along with other
airspace users. It provides a set of functions and services for managing a range of autonomous vehicle operations (e.g.
authenticating UAV, authorizing UAS services, managing UAS policies, and controlling UAV traffics in the airspace).
UAV controller: The UAV controller of a UAS enables a drone pilot to control an UAV.
UAV operator: the entity owning and operating a UAV.
UAS Container: A container to the 3GPP system that includes UUAA Aviation/Authorization Payload and/or C2
Aviation/Authorization Payload. The internal content of the individual payloads is transparent to the 3GPP system.
UAS Services: refers to establishment of connectivity for a UAS for communication with USS, for C2, for remote
identification, and for UAV location and tracking.
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USS communication: A communication between a UAV and a USS other than C2 communication, by means of user
plane data transmission for some UAS Services.
NOTE 2: The PDU session/PDN connection for C2 communication and the PDU session/PDN connection for USS
communication can be common or separate.
UUAA Authorization Payload: Contains application layer information optionally including UUAA result for UAV
consumption provided by the USS to the UAS which is transparent to the 3GPP System.
UUAA Aviation Payload: Contains application layer information provided by the UAS to USS and is transparent to
the 3GPP System
Uncrewed Aerial System (UAS): Composed of Uncrewed Aerial Vehicle (UAV) and related functionality, including
command and control (C2) links between the UAV and the control station, the UAV and the network, and for remote
identification. An UAS may comprise of a UAV and a UAV controller.
Unknown UAVs: A list of the UAVs to be identified in the target area and served by the PLMN as the result of the
UAV tracking requested by USS/UTM.
UUAA: UAV USS authentication and authorization procedure of the UAV to ensure that the UAV has successfully
registered with a USS and has therefore been authorized for operations by the USS. An UAV is authenticated and
authorized by USS via a UUAA procedure with the support of the 3GPP system before connectivity for UAS services is
enabled.
UUAA-MM: the UUAA procedure optionally performed during registration to a 5GS.
UUAA-SM: the UUAA procedure performed during the establishment of a PDU session and performed during the
establishment of a PDN connection.
3.2 Abbreviations
For the purposes of the present document, the abbreviations given in TR 21.905 [1] and the following apply. An
abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in
TR 21.905 [1].
BRID Broadcast Remote Identification
BVLOS Beyond Visual Line of Sight
C2 Command and Control
NRID Networked Remote Identification
RID Remote Identification
TPAE Third Party Authorized Entity
UAS Uncrewed Aerial System
UAV Uncrewed Aerial Vehicle
USS UAS Service Supplier
UTM Uncrewed Aerial System Traffic Management
UUAA USS UAV Authorization/Authentication
UUID Universal Unique Identifier

4 Architecture model and concepts
4.1 General concept
The architecture enhancements for UAVs introduce the following functionality:
- Authentication and authorization of a UAV with the USS during 5GS registration (optional).
- Authentication and authorization of a UAV with the USS during PDU session establishment and PDN
connection establishment.
- Support for USS authorization of C2 Communication.
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- A reference model for UAV tracking, supporting three UAV tracking modes: UAV location reporting mode,
UAV presence monitoring mode, and list of Aerial UEs in a geographic area. The 3GPP system supports
geofencing (for in-flight UAV) and geocaging (for UAV on the ground intending to fly) functionality in USS by
providing enablers such as location services, event notification to a subscribing USS, etc.
NOTE: Geofencing/geocaging mechanisms are an air traffic control functionality performed by the USS and are
out of scope of this specification. The 3GPP system provides enablers to support geofencing/geocaging
functionality in USS, e.g. location services, enablement of C2 connectivity, event notification to a
subscribing USS, etc. However, no specific geofencing/geocaging mechanisms are defined in 3GPP.
4.2 Architectural reference model
4.2.1 General
This specification covers UAV functionality provided by 5GC connected to NG-RAN and EPC connected to LTE.
The following functionality is defined for UAV support in the 3GPP system:
- An UAV is authenticated and authorized by USS via a USS UAV Authentication & Authorization (UUAA) with
the support of the 3GPP system before connectivity for UAS services is enabled.
- Depending on 3GPP network operator and/or regulatory requirements, the UUAA is performed:
- In 5GS: either as a separate procedure during the 5GS registration procedure (optional and based on specific
PLMN policies, USS requirements, and geographic regulatory requirements), or when the UAV requests user
plane resources for UAV operation (i.e. PDU session establishment). The UAV shall support UUAA during
Registration and PDU session establishment procedure. The network shall support UUAA during PDU
session establishment.
- In EPS: during the attach procedure and the corresponding PDN connection establishment. The network shall
support UUAA during PDN connection establishment. The UAV shall support UUAA during PDN
connection establishment procedure.
- A UAV that is provisioned with a CAA-Level UAV ID shall provide the CAA-Level UAV ID in 5GS in both
Registration and in PDU Session establishment. In EPC, a UAV that is provisioned with a CAA-Level UAV ID
provides the CAA-Level UAV ID in PDN Connection establishment in SM-PCO. The CN determine whether
UUAA is executed at 5GS registration or at PDU session/PDN Connection establishment, based on local
policies.
- The UUAA is performed at PDU session establishment when the UAV requests user plane resources for UAV
operation and the UAV provides its CAA Level ID during PDU session (PDN connection) establishment.
- The UAV flight authorization and UAV-UAVC pairing authorization is performed at PDU session/PDN
connection establishment/modification procedures.
- The 3GPP system supports USS authorization of pairing between a UAV and a networked UAVC or a UAVC
that connects to the UAV via Internet connectivity during either the establishment of the PDN connection/PDU
session for C2 communication or a modification of a PDN connection/PDU session either dedicated to C2
communication or common to USS communication and C2 communication. Modifications of the pairing or re-
authorization take place via modification of the established PDN connection/PDU session. During such
procedures, the USS provides to the 3GPP system information (e.g. QoS requirement, data flow descriptors, etc.)
that enable traffic between the UAV and the UAVC.
NOTE 1: How the USS is made aware of the UAVC is outside the scope of 3GPP in this Release.
- For EPC, the PDN connections used by UAV are served by SMF+PGW-C regardless of whether the UAV
support 5G NAS or whether their subscription allows access to 5GC. The APN(s) used by the UAV for
contacting USS or for C2 communication always resolves to a SMF+PWG-C.
The following architectural assumptions apply:
- It is assumed that the UAV trying to access UAS services using 3GPP connectivity is already registered with a
USS and has been assigned a CAA-Level-UAV ID. The procedure for UAV registration and assignment of
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CAA-Level-UAV ID is out of scope of 3GPP. The USS assigns to the UAV a CAA-Level UAV ID, or is made
aware of the assigned CAA-Level UAV ID.
- A UAV is associated with an Aerial subscription in the UDM. The Aerial subscription contains aerial UE
indication in the Access and Mobility Subscription data (to be used similarly to aerial UE indication defined in
EPS), an aerial service indication in the Session Management Subscription data for each DNN dedicated for
UAS services (C2 and UUAA-SM) which indicates that corresponding authentication/authorization has to be
done using API based mechanism.
- An UAV is identified by USS using a CAA-level UAV ID, and identified by the 3GPP System using a 3GPP
UAV ID assigned by the MNO:
- It is assumed that an aerial subscription associated to a UAV includes at least one GPSI to be used as 3GPP
UAV ID.
- A UAV is registered with the USS either before connecting with the 3GPP system or using plain internet
connectivity via the 3GPP system. Before registering for UAS services with the 3GPP system, the UAV shall be
provisioned with a CAA-Level UAV Identity.
- In roaming scenarios, it is assumed that access to USS is in the VPLMN, thus packet data connectivity for UAV-
USS communication is in local breakout, and the UAS NF function is located in the VPLMN.
- In this Release, the UAV uses 3GPP access (i.e. LTE & NR) for 3GPP UAV related operations.
- Activation of RAN aerial features for UAV accessing via E-UTRA reuses the existing mechanism defined in
TS 36.300 [7].
NOTE 2: In this Release, an UAV is served by single USS for the duration of the connectivity between the USS
and the UAV.
- One or more USS(s) may be present in a specific region and may manage UAVs over one or more 3GPP
networks.
- The 3GPP Network subscription for the UAV is not assumed to contain any information about the USS.
- The USS address, if known to the UAV, is configured in the UAV via mechanisms outside the scope of 3GPP.
4.2.2 Logical UAV Reference Architecture
TPAE
UAS NF/
N33 USS
NEF
Data
Network
N29, N30,
N51, .
N3
NG-RAN 5GC N6
UE
S1 SGi
(R)AN EPC
Figure 4.2.2-1: Logical 5GS and EPS architecture for UAV
NOTE 1: Provisioning of UAS services over EPC is based on the use of an SMF+PGW-C node.
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3GPP TS 23.256 version 17.9.0 Release 17 12 ETSI TS 123 256 V17.9.0 (2025-04)

HSS +
NEF+SCEF
UDM
(UAS NF)
N30
N10
PCF
S6a N29
N8
N7
SMF +
N15
T6a PGW-C
N51
S5-C
N4
UPF +
N11
PGW-U
S5-U
SGW
S11
N26
MME AMF
N3 N2
S1-U U
S1-MME
N1
E-UTRAN
NG-RAN
UE
UE
Figure 4.2.2-2: Non-roaming architecture for interworking between 5GS and EPC/E-UTRAN

HSS +
UDM
h-PCF
HPLMN
N24
VPLMN
NEF+SCEF
N10
N30
(UAS NF)
v-PCF
S6a
N29
N8
N7
T6a
SMF +
PGW-C
N15
S5-C
N4
N51
UPF +
N11
PGW-U
S5-U
SGW
S11
N26
AMF
MME
U
S1-U
N3 N2
S1-MME
N1
E-UTRAN NG-RAN
UE
UE
Figure 4.2.2-3: Local breakout roaming architecture for interworking between 5GS and EPC/E-UTRAN
ETSI
3GPP TS 23.256 version 17.9.0 Release 17 13 ETSI TS 123 256 V17.9.0 (2025-04)
NOTE 2: Transferring the UUAA context from AMF to MME when the UE moves from 5GS to EPS and the
UUAA was performed at 5GS registration is not supported on the N26 interface.
NOTE 3: No new UAV-specific functionality is defined for T6a.
4.2.3 5GS Non-roaming Reference Architecture
UAS NF/
NSSF NEF NRF PCF UDM AF
NEF
Nnssf Nnef Nnrf Npcf Nudm Naf
Nnef
Nausf Namf Nsmf
Nnssaaf
AUSF AMF SMF SCP
NSSAAF
N2 N4
UE N3
(R)AN UPF N6 DN
N9
Figure 4.2.3-1: 5G System non-roaming architecture for UAV
4.2.4 5GS Roaming Reference Architecture
UAS NF/
UDM NRF
NSSAAF
NRF PCF AF
NEF
NEF NSSF
Nudm
Nnef Naf Nnrf Nnssaaf
Npcf
Nnef Nnrf
Nnssf
vSEPP N32 hSEPP
Namf Nsmf
Npcf Nnef
Nausf
AMF SMF AUSF
NEF
PCF
N
HPLMN
VPLMN
UE
N6
(R)AN N3 UPF DN
N9
Figure 4.2.4-2: Roaming 5G System architecture for UAV - local breakout scenario in service-based
interface representation
4.2.5 Service-based interfaces
The 5G System Architecture for UAVs contains the service-based interfaces defined in TS 23.501 [2].
4.2.6 Reference points
The 5G System Architecture for UAV contains the reference points defined in TS 23.501 [2].
ETSI
3GPP TS 23.256 version 17.9.0 Release 17 14 ETSI TS 123 256 V17.9.0 (2025-04)
4.3 Functional entities
4.3.1 General
In addition to the 5GS functional entities defined in TS 23.501 [2] and the EPS functional entities defined in
TS 23.401 [6], the following functional entities are defined for UAS.
4.3.2 UAS NF
The UAS Network Function is supported by the NEF or SCEF+NEF and used for external exposure of services to the
USS. The UAS-NF makes use of existing NEF/SCEF exposure services for UAV authentication/authorization, for UAV
flight authorization, for UAV-UAVC pairing authorization, and related re-authentication/re-authorization and
revocation; for location reporting, presence monitoring, obtaining list of Aerial UEs in a geographic area and control of
QoS/traffic filtering for C2 communication.
The UAS NF may coordinate with the USS to assist CAA-Level UAV ID assignment.
A dedicated NEF may be deployed to provide only the UAS NF functionality, i.e. to support the UAS specific
features/APIs and the NEF features/APIs that are specified for capability exposure towards the USS.
For external exposure of services related to specific UAV(s), the UAS NF resides in the VPLMN, in order to interface
with country specific USS(es).
When CAPIF is supported by the UAS NF, the UAS NF supports the CAPIF API provider domain functions as
specified in TS 23.222 [4].
To support re-authentication/re-authorization and revocation request by USS, the UAS NF stores information as to
whether the re-authentication/re-authorization and revocation is towards an AMF or SMF/SMF+PGW-C and the
address of the serving AMF or SMF/SMF+PGW-C.
UAS NF stores the result of UUAA-MM procedures and the result of UUAA-SM procedures.
4.3.3 UAV
The UAV is a 3GPP UE supporting the UE functionality defined in TS 23.401 [6] and in TS 23.501 [2].
In additi
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