ETSI TS 133 320 V18.0.0 (2024-04)

Universal Mobile Telecommunications System (UMTS); LTE; Security of Home Node B (HNB) / Home evolved Node B (HeNB) (3GPP TS 33.320 version 18.0.0 Release 18)

RTS/TSGS-0333320vi00

General Information

• Status: Not Published
• Technical Committee: 3GPP SA 3 - Security
• Current Stage: 12 - Citation in the OJ (auto-insert)
• Completion Date: 30-Apr-2024

Standards Content (Sample)

TECHNICAL SPECIFICATION
Universal Mobile Telecommunications System (UMTS);
LTE;
Security of Home Node B (HNB)
/ Home evolved Node B (HeNB)
(3GPP TS 33.320 version 18.0.0 Release 18)

3GPP TS 33.320 version 18.0.0 Release 18 1 ETSI TS 133 320 V18.0.0 (2024-04)

Reference
RTS/TSGS-0333320vi00
Keywords
LTE,SECURITY,UMTS
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ETSI
3GPP TS 33.320 version 18.0.0 Release 18 2 ETSI TS 133 320 V18.0.0 (2024-04)
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ETSI
3GPP TS 33.320 version 18.0.0 Release 18 3 ETSI TS 133 320 V18.0.0 (2024-04)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 6
1 Scope . 7
2 References . 7
3 Definitions and abbreviations . 8
3.1 Definitions . 8
3.2 Abbreviations . 8
4 Overview of Security Architecture and Requirements . 9
4.1 System architecture of H(e)NB . 9
4.2 Network Elements . 10
4.2.1 H(e)NB . 10
4.2.2 Security Gateway (SeGW) . 10
4.2.3 H(e)NB Management System (H(e)MS) . 11
4.2.4 UE . 11
4.2.5 H(e)NB Gateway (H(e)NB-GW) and MME . 11
4.2.6 AAA Server and HSS . 11
4.2.7 Void . 11
4.2.8 Local Gateway (L-GW) . 11
4.3 Interfaces (Reference Points) . 11
4.3.1 Backhaul Link . 11
4.3.2 H(e)MS Interface . 11
4.3.3 Interface between SeGW and AAA Server, AAA Server and HSS . 11
4.3.4 Interface between H(e)NBs. 12
4.4 Security Requirements and Principles . 12
4.4.1 Operation . 12
4.4.2 Requirements on H(e)NB . 12
4.4.3 Requirements on SeGW . 13
4.4.4 Requirements on H(e)MS . 13
4.4.5 Requirements on Backhaul Link . 14
4.4.6 Requirements on H(e)MS Link . 14
4.4.7 Requirements on Local Gateway (L-GW) . 15
4.4.8 Requirements on the Direct Link between H(e)NBs . 15
4.4.9 Requirements on Verification of H(e)NB Identity and Operating Access Mode. 15
5 Security Features . 16
5.1 Secure Storage and Execution . 16
5.1.1 Hosting Party Module . 16
5.1.2 Trusted Environment (TrE). 16
5.1.2.1 General . 16
5.2 Device Mutual Authentication . 17
5.3 Hosting Party Mutual Authentication . 17
5.4 Other security features . 18
6 Security Procedures in H(e)NB . 19
6.1 Device Integrity Check . 19
6.1.1 Device Integrity Check Procedure . 19
6.1.2 Protection of Trusted Reference Value(s) . 19
6.2 Void . 19
6.3 Measures for Clock Protection . 19
6.3.1 Clock Synchronization Security Mechanisms for H(e)NB . 19
7 Security Procedures between H(e)NB and SeGW . 20
7.1 Device Validation . 20
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7.2 Device Authentication . 20
7.2.1 General . 20
7.2.2 SeGW and Device Mutual Authentication Procedure. 21
7.2.3 H(e)NB/IKEv2 Processing Requirements for SeGW Certificates . 22
7.2.4 SeGW/IKEv2 Processing Requirements for H(e)NB Certificates . 22
7.2.5 Security Profiles . 22
7.2.5.1 Profile for IKEv2 . 22
7.2.5.2 IKEv2 Certificate Profile . 23
7.2.5.2.1 IKEv2 Entity Certificates . 23
7.2.5.2.2 IKEv2 CA Certificates . 23
7.3 Hosting Party Authentication . 23
7.4 IPsec Tunnel Establishment . 24
7.5 Device Authorization . 24
8 Security Aspects of H(e)NB Management . 25
8.1 Location Verification . 25
8.1.1 General . 25
8.1.2 IP Address provided by H(e)NB . 25
8.1.3 IP Address and/or access line location identifier provided by broadband access provider . 25
8.1.4 Surrounding macro-cell information provided by H(e)NB . 25
8.1.5 GNSS information provided by H(e)NB . 25
8.1.6 Requirements . 26
8.2 Access Control Mechanisms for H(e)NB . 26
8.2.1 Non-CSG Method . 26
8.2.2 CSG Method . 26
8.3 Protection of H(e)MS traffic between H(e)MS and H(e)NB . 26
8.3.1 Connection to H(e)MS accessible on MNO Intranet . 26
8.3.2 Connection to H(e)MS accessible on public Internet . 27
8.3.2.1 General . 27
8.3.2.2 Device Validation . 27
8.3.3 TLS certificate profile . 28
8.3.3.1 TLS entity certificates . 28
8.3.3.2 TLS CA certificates. 28
8.3.4 TR-069 protocol profile . 29
8.4 Protection of SW Download . 29
8.5 Enrolment of H(e)NB to an Operator PKI . 30
8.5.1 General . 30
8.5.2 Enrolment Procedure . 30
8.5.3 Certificate Validation . 30
9 Security Aspects of Emergency Call Handling . 31
10 Security Aspects for Mobility . 32
10.1 Inbound mobility . 32
10.2 Outbound mobility . 32
11 Security Procedures for Direct Interfaces between Base Stations . 33
11.1 General . 33
11.2 Direct Link between two H(e)NBs . 33
Annex A (informative): Authentication Call-flows . 34
A.1 Device Authentication Call-flow Example . 34
A.2 Combined Device and HP Authentication Call-flow Example . 35
Annex B (informative): Location Verification Examples . 38
B.1 Example of Location verification based on IP address and line identifier in NASS . 38
B.2 Example process of location verification when the verifying node receive different types of
location information . 38
Annex C: Change history . 40
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History . 42

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Foreword
rd
This Technical Specification has been produced by the 3 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.
ETSI
3GPP TS 33.320 version 18.0.0 Release 18 7 ETSI TS 133 320 V18.0.0 (2024-04)
1 Scope
The present document specifies the security architecture for the H(e)NB subsystem. This includes security requirements
on Home Node Bs, Home eNode Bs, and other H(e)NB-associated network nodes (e.g. SeGW and H(e)MS), as well as
the procedures and features which are provided to meet those requirements.
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 32.583: "Telecommunications management; Home Node B (HNB) Operations,
Administration, Maintenance and Provisioning (OAM&P); Procedure flows for Type 1 interface
HNB to HNB Management System (HMS) ".
[3] IETF RFC 4187: "Extensible Authentication Protocol Method for 3rd Generation Authentication
and Key Agreement (EAP-AKA) ".
[4] - [5] Void.
[6] IETF RFC 4739: "Multiple Authentication Exchanges in the Internet Key Exchange (IKEv2
Protocol”, Nov 2006".
[7] 3GPP TS 33.310: "Network Domain Security (NDS); Authentication Framework (AF) ".
[8] 3GPP TS 23.003: "Numbering, addressing and identification".
[9] 3GPP TS 33.210: "3G security; Network Domain Security (NDS); IP network layer security".
[10] 3GPP TS 33.234: "3G security; Wireless Local Area Network (WLAN) interworking security".
[11] 3GPP TS 32.593: "Telecommunication management; Procedure flows for Type 1 interface
H(e)NB to H(e)NB Management System (H(e)MS) ".
[12] 3GPP TS 25.467: "UTRAN architecture for 3G Home Node B (HNB); Stage 2".
[13] - [14] Void.
[15] The Broadband Forum TR-069: "CPE WAN Management Protocol v1.1", Issue 1 Amendment 2,
December 2007.
[16] - [17] Void.
[18] ETSI ES 282 004 (V1.1.1): "Telecommunications and Internet Converged Services and Protocols
for Advanced Networking (TISPAN); NGN functional architecture; Network Attachment Sub-
System (NASS) ", 2006.
[19] ETSI ES 283 035 (V1.1.1): "Telecommunications and Internet Converged Services and Protocols
for Advanced Networking (TISPAN); Network Attachment Sub-System (NASS); e2 interface
based on the DIAMETER protocol", 2006.
[20] 3GPP TS 33.102: "3G security; Security architecture".
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[21] 3GPP TS 33.401: "3GPP System Architecture Evolution (SAE): Security architecture".
[22] IETF RFC 2560: "X.509 Internet Public Key Infrastructure Online Certificate Status Protocol –
OCSP"
[23] Open Mobile Alliance OMA-WAP-OCSP V1.0: "Online Certificate Status Protocol Mobile
Profile". URL: http://www.openmobilealliance.org/
[24] IETF RFC 4806: "Online Certificate Status Protocol (OCSP) Extensions to IKEv2".
[25] Void.
[26] IETF RFC 5280: "Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation
List (CRL) Profile".
[27] 3GPP TS 36.300: "Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal
Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2".
[28] 3GPP TS 25.367: "Mobility procedures for Home Node B (HNB); Overall description; Stage 2".
[29] 3GPP TS 23.060: "General Packet Radio Service (GPRS); Service description; Stage 2".
[30] 3GPP TS 23.401: "General Packet Radio Service (GPRS) enhancements for Evolved Universal
Terrestrial Radio Access Network (E-UTRAN) access".
[31] 3GPP TS 22.220: "Technical Specification Group Services and System Aspects; Service
requirements for Home Node B (HNB) and Home eNode B (HeNB)".
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].
CSG: A closed subscriber group identifies subscribers of an operator who are permitted to access one or more cells of
the PLMN of but having restricted access (“CSG cells”)
Hosting party: The party hosting the H(e)NB and having a contract with the PLMN operator.
Security Gateway: Element at the edge of an operator’s security domain terminating security association(s) for the
backhaul link between H(e)NB and network.
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].
AAA Authentication, Authorization, and Accounting
ACL Access Control List
ACS Auto-Configuration Server
AKA Authentication and Key Agreement
CA Certification Authority
CPE Customer Premises Equipment
CRL Certificate Revocation List
CSG Closed Subscriber Group
DNS Domain Name System
DPD Dead Peer Detection
eNB Evolved Node-B
EAP Extensible Authentication Protocol
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ESP Encapsulating Security Payload
E-UTRAN Evolved UTRAN
FQDN Fully Qualified Domain Name
GNSS Global Navigation Satellite System
H(e)NB Home NodeB or Home eNodeB
H(e)NB-GW Home (e)NodeB Gateway
H(e)MS Home NodeB Management or Home eNodeB Management System
HeMS Home eNodeB Management System
HeNB Home eNodeB
HMS Home NodeB Management System
HNB Home NodeB
HP Hosting Party
HPM HP Module
HW Hardware
IKE Internet Key Exchange
IMSI International Mobile Subscriber Identity
L-GW Local Gateway
LIPA Local IP Access
LTE Long Term Evolution
MME Mobility Management Entity
MSK Master Session Key
NAPT Network Address Port Translation
NAT Network Address Translation
NAT-T NAT-Traversal
OCSP Online Certificate Status Protocol
PKI Public Key Infrastructure
SA Security Association
SeGW Security Gateway
SGSN Serving GPRS Support Node
S-GW Serving Gateway
TLS Transport Layer Security
TrE Trusted Environment
UDP User Datagram Protocol
UICC Universal Integrated Circuit Card
URI Uniform Resource Identifier
URL Uniform Resource Locator
USIM Universal Subscriber Identity Module
UMTS Universal Mobile Telecommunications System
UTRAN Universal Terrestrial Radio Access Network
WAP Wireless Application Protocol

4 Overview of Security Architecture and Requirements
4.1 System architecture of H(e)NB
Operator’s security AAA
domain(s)
Server/HSS
L-GW
UE H(e)NB insecure link SeGW
H(e)NB-GW
H(e)MS
H(e)MS
Figure 4.1.1: System Architecture of H(e)NB
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Description of the system architecture:
- Air interface between UE and H(e)NB should be backwards compatible to the air interface in UTRAN or E-
UTRAN.
- H(e)NB accesses the operator’s security domain via a Security Gateway (SeGW). The backhaul between
H(e)NB and SeGW may be insecure.
- Security Gateway represents the operator’s core network with respect to performing mutual authentication with
the H(e)NB.
- AAA server authenticates the hosting party based on the authentication information retrieved from HSS when
hosting party authentication is performed.
- Security tunnel is established between H(e)NB and Security Gateway to protect information transmitted in
backhaul link.
- HNB-GW performs mandatory UE access control and HNB performs optional UE access control in the case of
non-CSG capable UEs or non-CSG capable HNBs. SeGW and HNB-GW are logically separate entities within
operator’s network, with the SeGW located in front of the HNB-GW. The SeGW may be integrated into the
HNB-GW. If the SeGW and the HNB-GW are not integrated, then the interface between the HNB-GW and the
SeGW may be protected using NDS/IP as specified in TS 33.210 [9]. The interface between HNB-GW and
MSC/SGSN may be protected using NDS/IP.
- HeNB-GW is optional to deploy. When HeNB-GW is not deployed, the SeGW is located at the edge of the core
network and the interface between SeGW and MME/S-GW may be protected using NDS/IP as specified in
TS 33.210 [9]. When HeNB-GW is deployed, then SeGW and HeNB-GW are logically separate entities, with
the SeGW located in front of the HeNB-GW. The SeGW may be integrated into HeNB-GW. If the SeGW and
the HeNB-GW are not integrated, then the interface between the HeNB-GW and the SeGW may be protected
using NDS/IP, the interface between HeNB-GW and MME/S-GW may be protected using NDS/IP.
- HMS as specified in TS 32.583 [2] and/or HNB-GW as specified in TS 25.467 [12] performs location
verification of HNB.
- HeMS as specified in TS 32.593 [11] performs location verification of HeNB.
- Secure communication is required to H(e)NB Management System (H(e)MS).
- L-GW is optional to deploy. If L-GW is deployed, then the secured interface between H(e)NB and Security
Gateway is used by the L-GW to communicate with the core network.
4.2 Network Elements
4.2.1 H(e)NB
The H(e)NB is a network element that connects User Equipment via its radio interface to the operator’s core network.
The backhaul link to the operator’s network is a broadband connection. A H(e)NB is typically deployed in customers’
premises.
NOTE: The term H(e)NB refers to both Home NodeB (HNB) and Home eNodeB (HeNB), when both are meant
without distinction.
4.2.2 Security Gateway (SeGW)
The SeGW is a network element at the border of a security domain of the operator. If a H(e)NB-GW is deployed the
SeGW is located in front of the H(e)NB-GW, else it is located at the edge of the core network. After successful mutual
authentication between the H(e)NB and the SeGW, the SeGW connects the H(e)NB to the operator’s security domain.
Any connection between the H(e)NB and the H(e)NB-GW or core network is tunnelled through the SeGW.
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4.2.3 H(e)NB Management System (H(e)MS)
The H(e)MS is a management server that configures the H(e)NB according to the operator’s policy. H(e)MS is also
capable of installing software updates on the H(e)NB. The H(e)MS server may be located inside the operator’s access or
core network (accessible on the MNO Intranet) or outside of it (accessible on the public Internet).
The HMS is specified in TS 32.583 [2].
The HeMS is specified in TS 32.593 [11].
4.2.4 UE
UE is a standard user equipment for UMTS (for HNB) or LTE (for HeNB).
4.2.5 H(e)NB Gateway (H(e)NB-GW) and MME
HNB-GW is specified in TS 25.467 [12] and HeNB-GW is specified in TS 36.300 [27].
4.2.6 AAA Server and HSS
HSS stores the subscription data and authentication information of the H(e)NBs. When hosting party authentication is
required, AAA server authenticates the hosting party based on the authentication information retrieved from HSS.
4.2.7 Void
4.2.8 Local Gateway (L-GW)
L-GW is specified in TS 23.060 [29] and in TS 23.401 [30]. The Local IP Access (LIPA) is achieved using a L-GW
colocated with the H(e)NB. The L-GW is connected to the Serving Gateway (S-GW) or to the SGSN via the SeGW.
4.3 Interfaces (Reference Points)
4.3.1 Backhaul Link
The backhaul link used between H(e)NB and SeGW provides a secure tunnel carrying both the user plane data and the
control plane data that are transmitted between the H(e)NB and the H(e)NB-GW or network elements in the core
network.
NOTE: If LIPA is activated, the secured backhaul link between the H(e)NB and SeGW is used by the L-GW to
communicate with the core network.
H(e)MS traffic is also tunnelled through this secure backhaul link, if the H(e)MS is accessible on the MNO Intranet.
The backhaul link may also carry other data between H(e)NB and operator’s radio access or core network, e.g. time
protocol traffic.
4.3.2 H(e)MS Interface
The H(e)MS Interface between the H(e)NB and the H(e)MS server shall provide a secure connection carrying
configuration data., SW updates and additional data, e.g. location information.
4.3.3 Interface between SeGW and AAA Server, AAA Server and HSS
The interface between the SeGW and AAA Server provides a secure connection carrying authentication, authorization,
and related information.
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The interface between AAA Server and HSS provides a secure connection for the retrieval of authentication vectors
(e.g. for hosting party authentication) and retrieval of H(e)NB access-related information for HPM.
4.3.4 Interface between H(e)NBs
The interface used between two HNBs or between two HeNBs provides a direct link carrying both the user plane data
and the control plane data. The interface is specified as Iurh interface between two HNBs (cf. TS 25.467 [12]) and as
X2 interface between two HeNBs (cf. TS 36.300 [27]). It is used during handover between the two base stations
connected by this link.
NOTE: This clause handles the direct connection between two network elements. If the messages between two
network elements are routed via the core network using the existing backhaul links to the SeGW(s), then
a direct link in the sense of this clause is not necessary.
4.4 Security Requirements and Principles
4.4.1 Operation
The requirements on operation are:
- Only algorithms of adequate cryptographic strength shall be used for authentication and protection of
confidentiality and integrity.
- Modifications of Hosting Party controlled information by the operator shall only be allowed with the permission
of the Hosting Party.
- The extent of Hosting Party controllable information shall be controlled by the operator.
- IMSIs of UEs connected to H(e)NB shall not be revealed to the Hosting Party of the H(e)NB.
4.4.2 Requirements on H(e)NB
The requirements on the H(e)NB are:
- The integrity of the H(e)NB shall be validated before any connection to the H(e)NB-GW or into the core
network is established.
- The H(e)NB shall be authenticated by the SeGW based on a globally unique and permanent H(e)NB identity. If
the H(e)NB was enrolled to an operator PKI according to clause 8.5 of the present document, then the H(e)NB
may alternatively be authenticated by the SeGW based on the identity provided by the operator.
- The H(e)NB shall authenticate the SeGW based on SeGW certificate.
- Optionally the hosting party of the H(e)NB may be authenticated by the SeGW in cooperation with the AAA
server using EAP-AKA as specified in RFC 4187 [3].
- If hosting party authentication is used, the H(e)NB shall shut down its air interface and disconnect from the
operator’s core network on removal of the HPM which was used for authentication towards the MNO.
- The H(e)NB may support the establishment of direct links to other base stations (i.e. HNB to HNB and HeNB to
HeNB) as specified in clause 4.3.4. If establishment of direct links is supported the H(e)NB shall support
enrolment to the operator PKI as specified in clause 8.5. Once the H(e)NB is enrolled to the operator PKI, it shall
use the operator device certificate. The usage of operator PKI enrolment shall be securely configurable. If the
default configuration is set in the factory it shall be set to no usage of operator PKI enrolment.
NOTE: Setting the default configuration to no usage of PKI enrolment allows for H(e)NBs to be deployed in
networks containing H(e)NBs with or without support of PKI enrolment. On the other hand this requires
e.g. a connection to initial H(e)MS based on authentication using the vendor certificate to securely switch
the H(e)NB to enroll to the operator PKI, and to provide the operator root certificate as specified in clause
8.5.2.
ETSI
3GPP TS 33.320 version 18.0.0 Release 18 13 ETSI TS 133 320 V18.0.0 (2024-04)
- If a direct link to another base station secured by security procedures as specified in clause 4.4.8 is established,
the H(e)NB shall authenticate the other base station based on the identity provided by the operator to the other
base station.
- If a direct link to another base station secured by security procedures as specified in clause 4.4.8 is established,
the H(e)NB shall be authenticated by the other base station based on the identity provided by the operator to the
H(e)NB.
- The H(e)NB shall establish direct links with other base stations only after establishment of the backhaul link. If
the backhaul link is terminated, then also all direct links to other base stations shall be terminated.
- The H(e)NB shall authenticate the H(e)MS, if the H(e)MS is accessed on the public Internet.
- The H(e)NB shall be authenticated by the H(e)MS using the same identity as for authentication to the SeGW, if
the H(e)MS is accessed on the public Internet.
- The configuration and the software of the H(e)NB shall only be updated in a secure way, i.e. the integrity of the
configuration data including the licensed radio parameters and the integrity of the software updates must be
verified.
- Sensitive data including cryptographic keys, authentication credentials, user information, user plane data and
control plane data shall not be accessible at the H(e)NB in plaintext to unauthorized access.
- The time base of the H(e)NB shall be synchronized to the core network.
- The location of the H(e)NB shall be reliably transferred to the network.
- The H(e)NB shall be capable of filtering unauthenticated traffic received from the access network. Operator
policy shall control which types of unauthenticated traffic are filtered.
- The H(e)NB shall implement a mechanism to shut down the air interface within a certain time period after the
connection between H(e)NB and the rest of the operator network went out of service. This time period and the
usage of the mechanism shall be configurable by the operator.
- The H(e)NB shall only activate its air interface after successful establishment of the backhaul link (cf. sub-clause
4.4.5 of the present document). The establishment of the backhaul link happens as a result of successful integrity
validation, device mutual authentication between H(e)NB and SeGW, and optional hosting party authentication
- All security requirements of the eNB secure environment of TS 33.401 [21] clause 5.3 shall apply to the HeNB.
Security measures to establish this secure environment shall be assured by the TrE (subclause 5.1.2) where they
fall under the capability of the TrE.
4.4.3 Requirements on SeGW
The requirements on the SeGW are:
- The SeGW shall be authenticated by the H(e)NB using a SeGW certificate. The SeGW certificate shall be signed
by a CA trusted by the operator.
- The SeGW shall authenticate the H(e)NB based on H(e)NB certificate.
- The SeGW may authenticate the hosting party of the H(e)NB in cooperation with the AAA server using EAP-
AKA as specified in RFC 4187 [3].
- The SeGW shall allow the H(e)NB access to the H(e)NB-GW or core network only after successful completion
of all required authentications.
- Any unauthenticated traffic from the H(e)NB shall be filtered out at the SeGW.
4.4.4 Requirements on H(e)MS
The requirements on the H(e)MS are:
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3GPP TS 33.320 version 18.0.0 Release 18 14 ETSI TS 133 320 V18.0.0 (2024-04)
- The H(e)MS shall be authenticated by the H(e)NB if the H(e)MS is accessible on the public Internet and may be
authenticated by H(e)NB if the H(e)MS is accessible on the MNO Intranet using a H(e)MS certificate. The
H(e)MS certificate shall be provided by a MNO trusted CA.
- The H(e)MS shall authenticate the identity of the H(e)NB if the H(e)MS is accessible on the public Internet and
may authenticate the identity of the H(e)NB if the H(e)MS is accessible on the MNO Intranet, using a H(e)NB
certificate. This identity shall be the same as used during backhaul link establishment (cf. sub-clause 4.4.5 of the
present document).
- The H(e)MS may securel
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