ETSI TS 138 423 V15.7.0 (2020-04)

5G; NG-RAN; Xn Application Protocol (XnAP) (3GPP TS 38.423 version 15.7.0 Release 15)

RTS/TSGR-0338423vf70

General Information

• Status: Published
• Publication Date: 07-Apr-2020
• Technical Committee: 3GPP RAN 3 - lub specification, lur specification, lu specification and UTRAN & O&M
• Current Stage: 12 - Completion
• Completion Date: 08-Apr-2020

Standards Content (Sample)

ETSI TS 138 423 V15.7.0 (2020-04)






TECHNICAL SPECIFICATION
5G;
NG-RAN;
Xn Application Protocol (XnAP)
(3GPP TS 38.423 version 15.7.0 Release 15)

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3GPP TS 38.423 version 15.7.0 Release 15 1 ETSI TS 138 423 V15.7.0 (2020-04)



Reference
RTS/TSGR-0338423vf70
Keywords
5G
ETSI
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3GPP TS 38.423 version 15.7.0 Release 15 2 ETSI TS 138 423 V15.7.0 (2020-04)
Intellectual Property Rights
Essential patents
IPRs essential or potentially essential to normative deliverables may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
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Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
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Legal Notice
This Technical Specification (TS) has been produced by ETSI 3rd Generation Partnership Project (3GPP).
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Modal verbs terminology
In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and
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"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
ETSI

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3GPP TS 38.423 version 15.7.0 Release 15 3 ETSI TS 138 423 V15.7.0 (2020-04)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 10
1 Scope . 11
2 References . 11
3 Definitions, symbols and abbreviations . 12
3.1 Definitions . 12
3.2 Abbreviations . 13
4 General . 13
4.1 Procedure specification principles . 13
4.2 Forwards and backwards compatibility . 14
4.3 Specification notations . 14
5 XnAP services . 14
5.1 XnAP procedure modules . 14
5.2 Parallel transactions . 14
6 Services expected from signalling transport . 14
7 Functions of XnAP . 15
8 XnAP procedures . 15
8.1 Elementary procedures . 15
8.2 Basic mobility procedures . 17
8.2.1 Handover Preparation . 17
8.2.1.1 General . 17
8.2.1.2 Successful Operation . 17
8.2.1.3 Unsuccessful Operation . 20
8.2.1.4 Abnormal Conditions . 20
8.2.2 SN Status Transfer . 20
8.2.2.1 General . 20
8.2.2.2 Successful Operation . 21
8.2.2.3 Unsuccessful Operation . 21
8.2.2.4 Abnormal Conditions . 21
8.2.3 Handover Cancel . 22
8.2.3.1 General . 22
8.2.3.2 Successful Operation . 22
8.2.3.3 Unsuccessful Operation . 22
8.2.3.4 Abnormal Conditions . 22
8.2.4 Retrieve UE Context . 22
8.2.4.1 General . 22
8.2.4.2 Successful Operation . 23
8.2.4.3 Unsuccessful Operation . 23
8.2.4.4 Abnormal Conditions . 24
8.2.5 RAN Paging . 24
8.2.5.1 General . 24
8.2.5.2 Successful operation. 24
8.2.5.3 Unsuccessful Operation . 24
8.2.5.4 Abnormal Condition. 24
8.2.6 XN-U Address Indication . 24
8.2.6.1 General . 24
8.2.6.2 Successful Operation . 25
8.2.6.3 Unsuccessful Operation . 25
8.2.6.4 Abnormal Conditions . 25
ETSI

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3GPP TS 38.423 version 15.7.0 Release 15 4 ETSI TS 138 423 V15.7.0 (2020-04)
8.2.7 UE Context Release . 26
8.2.7.1 General . 26
8.2.7.2 Successful Operation . 26
8.2.7.3 Unsuccessful Operation . 27
8.2.7.4 Abnormal Conditions . 27
8.3 Procedures for Dual Connectivity . 27
8.3.1 S-NG-RAN node Addition Preparation . 27
8.3.1.1 General . 27
8.3.1.2 Successful Operation . 28
8.3.1.3 Unsuccessful Operation . 31
8.3.1.4 Abnormal Conditions . 31
8.3.2 S-NG-RAN node Reconfiguration Completion . 32
8.3.2.1 General . 32
8.3.2.2 Successful Operation . 32
8.3.2.3 Abnormal Conditions . 32
8.3.3 M-NG-RAN node initiated S-NG-RAN node Modification Preparation . 32
8.3.3.1 General . 32
8.3.3.2 Successful Operation . 33
8.3.3.3 Unsuccessful Operation . 38
8.3.3.4 Abnormal Conditions . 38
8.3.4 S-NG-RAN node initiated S-NG-RAN node Modification . 39
8.3.4.1 General . 39
8.3.4.2 Successful Operation . 39
8.3.4.3 Unsuccessful Operation . 41
8.3.4.4 Abnormal Conditions . 42
8.3.5 S-NG-RAN node initiated S-NG-RAN node Change . 42
8.3.5.1 General . 42
8.3.5.2 Successful Operation . 43
8.3.5.3 Unsuccessful Operation . 43
8.3.5.4 Abnormal Conditions . 43
8.3.6 M-NG-RAN node initiated S-NG-RAN node Release . 44
8.3.6.1 General . 44
8.3.6.2 Successful Operation . 44
8.3.6.3 Unsuccessful Operation . 45
8.3.6.4 Abnormal Conditions . 45
8.3.7 S-NG-RAN node initiated S-NG-RAN node Release . 45
8.3.7.1 General . 45
8.3.7.2 Successful Operation . 46
8.3.7.3 Unsuccessful Operation . 46
8.3.7.4 Abnormal Conditions . 46
8.3.8 S-NG-RAN node Counter Check . 46
8.3.8.1 General . 46
8.3.8.2 Successful Operation . 47
8.3.8.3 Unsuccessful Operation . 47
8.3.8.4 Abnormal Conditions . 47
8.3.9 RRC Transfer . 47
8.3.9.1 General . 47
8.3.9.2 Successful Operation . 48
8.3.9.3 Unsuccessful Operation . 48
8.3.9.4 Abnormal Conditions . 48
8.3.10 Notification Control Indication . 48
8.3.10.1 General . 48
8.3.10.2 Successful Operation – M-NG-RAN node initiated . 49
8.3.10.3 Successful Operation – S-NG-RAN node initiated . 49
8.3.10.4 Abnormal Conditions . 49
8.3.11 Activity Notification . 49
8.3.11.1 General . 49
8.3.11.2 Successful Operation . 50
8.3.11.3 Abnormal Conditions . 50
8.3.12 E-UTRA – NR Cell Resource Coordination . 50
8.3.12.1 General . 50
8.3.12.2 Successful Operation . 51
ETSI

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3GPP TS 38.423 version 15.7.0 Release 15 5 ETSI TS 138 423 V15.7.0 (2020-04)
8.3.13 Secondary RAT Data Usage Report . 52
8.3.13.1 General . 52
8.3.13.2 Successful Operation . 52
8.3.13.3 Unsuccessful Operation . 52
8.3.13.4 Abnormal Conditions . 52
8.4 Global procedures. 52
8.4.1 Xn Setup . 52
8.4.1.1 General . 52
8.4.1.2 Successful Operation . 53
8.4.1.3 Unsuccessful Operation . 54
8.4.1.4 Abnormal Conditions . 54
8.4.2 NG-RAN node Configuration Update . 54
8.4.2.1 General . 54
8.4.2.2 Successful Operation . 55
8.4.2.3 Unsuccessful Operation . 57
8.4.2.4 Abnormal Conditions . 57
8.4.3 Cell Activation . 57
8.4.3.1 General . 57
8.4.3.2 Successful Operation . 57
8.4.3.3 Unsuccessful Operation . 58
8.4.3.4 Abnormal Conditions . 58
8.4.4 Reset . 58
8.4.4.1 General . 58
8.4.4.2 Successful Operation . 59
8.4.4.3 Unsuccessful Operation . 59
8.4.4.4 Abnormal Conditions . 59
8.4.5 Error Indication . 60
8.4.5.1 General . 60
8.4.5.2 Successful Operation . 60
8.4.5.3 Unsuccessful Operation . 60
8.4.5.4 Abnormal Conditions . 60
8.4.6 Xn Removal . 60
8.4.6.1 General . 60
8.4.6.2 Successful Operation . 61
8.4.6.3 Unsuccessful Operation . 61
8.4.6.4 Abnormal Conditions . 61
9 Elements for XnAP Communication . 62
9.0 General . 62
9.1 Message Functional Definition and Content . 62
9.1.1 Messages for Basic Mobility Procedures . 62
9.1.1.1 HANDOVER REQUEST . 62
9.1.1.2 HANDOVER REQUEST ACKNOWLEDGE. 64
9.1.1.3 HANDOVER PREPARATION FAILURE . 65
9.1.1.4 SN STATUS TRANSFER . 65
...