Foreword1 Scope2 References3 Definitions, symbols and abbreviations4 General5 X2AP services6 Services expected from signalling transport7 Functions of X2AP8 X2AP procedures8.1 Elementary procedures8.2 Basic mobility procedures8.3 Global Procedures8.4 X2 Release8.5 X2AP Message Transfer8.6 Procedures for Dual Connectivity8.7 Procedures for E-UTRAN-NR Dual Connectivity8.7.1 EN-DC X2 Setup8.7.2 EN-DC Configuration Update8.7.3 EN-DC Cell Activation8.7.4 SgNB Addition Preparation8.7.5 SgNB Reconfiguration Completion8.7.6 MeNB initiated SgNB Modification Preparation8.7.7 SgNB initiated SgNB Modification8.7.8 SgNB Change8.7.9 MeNB initiated SgNB Release8.7.10 SgNB initiated SgNB Release8.7.11 SgNB Counter Check8.7.12 RRC Transfer8.7.13 Secondary RAT Data Usage Report8.7.14 Partial reset of EN-DC8.7.15 E-UTRA – NR Cell Resource Coordination8.7.16 SgNB Activity Notification8.7.17 gNB Status Indication8.7.18 EN-DC Configuration Transfer8.7.19 Trace Start8.7.20 Deactivate Trace8.7.21 EN-DC Resource Status Reporting Initiation8.7.22 EN-DC Resource Status Reporting8.7.23 Cell Traffic Trace8.7.24 UE Radio Capability ID Mapping8.7.25 Conditional PSCell Change Cancel8.8 IAB Procedures9 Elements for X2AP Communication9.0 General9.1 Message Functional Definition and Content9.1.1 Messages for Basic Mobility Procedures9.1.2 Messages for global procedures9.1.3 Messages for Dual Connectivity Procedures9.1.4 Messages for E-UTRAN-NR Dual Connectivity Procedures9.1.5 Messages for IAB Procedures9.2 Information Element definitions9.2.0 General9.2.1 GTP Tunnel Endpoint9.2.2 Trace Activation9.2.3 Handover Restriction List9.2.4 PLMN Identity9.2.5 DL Forwarding9.2.6 Cause9.2.7 Criticality Diagnostics9.2.8 Served Cell Information9.2.9 E-RAB Level QoS Parameters9.2.10 GBR QoS Information9.2.11 Bit Rate9.2.12 UE Aggregate Maximum Bit Rate9.2.13 Message Type9.2.14 ECGI9.2.15 COUNT Value9.2.16 GUMMEI9.2.17 UL Interference Overload Indication9.2.18 UL High Interference Indication9.2.19 Relative Narrowband Tx Power (RNTP)9.2.20 GU Group Id9.2.21 Location Reporting Information9.2.22 Global eNB ID9.2.23 E-RAB ID9.2.24 eNB UE X2AP ID9.2.25 Subscriber Profile ID for RAT/Frequency priority9.2.25a Additional RRM Policy Index9.2.26 EARFCN9.2.27 Transmission Bandwidth9.2.28 E-RAB List9.2.29 UE Security Capabilities9.2.30 AS Security Information9.2.31 Allocation and Retention Priority9.2.32 Time To Wait9.2.33 SRVCC Operation Possible9.2.34 Hardware Load Indicator9.2.35 S1 TNL Load Indicator9.2.36 Load Indicator9.2.37 Radio Resource Status9.2.38 UE History Information9.2.39 Last Visited Cell Information9.2.40 Last Visited E-UTRAN Cell Information9.2.41 Last Visited GERAN Cell Information9.2.42 Cell Type9.2.43 Number of Antenna Ports9.2.44 Composite Available Capacity Group9.2.45 Composite Available Capacity9.2.46 Cell Capacity Class Value9.2.47 Capacity Value9.2.48 Mobility Parameters Information9.2.49 Mobility Parameters Modification Range9.2.50 PRACH Configuration9.2.51 Subframe Allocation9.2.52 CSG Membership Status9.2.53 CSG ID9.2.54 ABS Information9.2.55 Invoke Indication9.2.56 MDT Configuration9.2.57 Void9.2.58 ABS Status9.2.59 Management Based MDT Allowed9.2.60 MultibandInfoList9.2.61 M3 Configuration9.2.62 M4 Configuration9.2.63 M5 Configuration9.2.64 MDT PLMN List9.2.65 EARFCN Extension9.2.66 COUNT Value Extended9.2.67 Extended UL Interference Overload Info9.2.68 RNL Header9.2.69 Masked IMEISV9.2.70 Expected UE Behaviour9.2.71 Expected UE Activity Behaviour9.2.72 SeNB Security Key9.2.73 SCG Change Indication9.2.74 CoMP Information9.2.75 CoMP Hypothesis Set9.2.76 RSRP Measurement Report List9.2.77 Dynamic DL transmission information9.2.78 ProSe Authorized9.2.79 CSI Report9.2.80 Wideband CQI9.2.81 Subband CQI9.2.82 COUNT Value for PDCP SN Length 189.2.83 LHN ID9.2.84 Correlation ID9.2.85 UE Context Kept Indicator9.2.86 eNB UE X2AP ID Extension9.2.87 M6 Configuration9.2.88 M7 Configuration9.2.89 Tunnel Information9.2.90 X2 Benefit Value9.2.91 Resume ID9.2.92 Bearer Type9.2.93 V2X Services Authorized9.2.94 Offset of NB-IoT Channel Number to EARFCN9.2.95 WT ID9.2.96 WT UE XwAP ID9.2.97 UE Sidelink Aggregate Maximum Bit Rate9.2.98 NR Neighbour Information9.2.99 Extended Bit Rate9.2.100 en-gNB UE X2AP ID9.2.101 SgNB Security Key9.2.102 Target SgNB ID Information9.2.103 SCG Configuration Query9.2.104 Delivery Status9.2.105 Void9.2.106 NR Frequency Info9.2.107 NR UE Security Capabilities9.2.108 EN-DC Resource Configuration9.2.109 PDCP Change Indication9.2.110 Served NR Cell Information9.2.111 NR CGI9.2.112 Global en-gNB ID9.2.113 Void9.2.114 NR Transmission Bandwidth9.2.115 Cell Assistance Information9.2.116 MeNB Resource Coordination Information9.2.117 SgNB Resource Coordination Information9.2.118 UL Configuration9.2.119 RLC Mode9.2.120 Secondary RAT Usage Report List9.2.121 UE Application layer measurement configuration9.2.122 DRB ID9.2.123 SUL Information9.2.124 Packet Loss Rate9.2.125 Protected E-UTRA Resource Indication9.2.126 Data Traffic Resource Indication9.2.127 Data Traffic Resources9.2.128 Reserved Subframe Pattern9.2.129 Aerial UE subscription information9.2.130 User plane traffic activity report9.2.131 RLC Status9.2.132 RRC config indication9.2.133 PDCP SN Length9.2.134 Bluetooth Measurement Configuration9.2.135 WLAN Measurement Configuration9.2.136 Subscription Based UE Differentiation Information9.2.137 Duplication activation9.2.138 LCID9.2.139 MeNB Coordination Assistance Information9.2.140 SgNB Coordination Assistance Information9.2.141 Desired Activity Notification Level9.2.142 Location Information at SgNB9.2.143 Interface Instance Indication9.2.144 NB-IoT UL DL Alignment Offset9.2.145 Lower Layer presence status change9.2.146 Cell and Capacity Assistance Information9.2.147 Maximum Cell List Size9.2.148 Message Oversize Notification9.2.149 TNL Transport Layer Address Info9.2.150 CP Transport Layer Information9.2.151 TNL Association Usage9.2.152 RAN UE NGAP ID9.2.153 EPC Handover Restriction List Container9.2.154 DAPS Request Information9.2.155 DAPS Response Information9.2.156 Maximum Number of CHO Preparations9.2.157 Ethernet Type9.2.158 NR V2X Services Authorized9.2.159 NR UE Sidelink Aggregate Maximum Bit Rate9.2.160 PC5 QoS Parameters9.2.161 TNL Capacity Indicator9.2.162 NR Radio Resource Status9.2.163 NR Composite Available Capacity Group9.2.164 NR Composite Available Capacity9.2.165 NR Cell Capacity Class Value9.2.166 NR Capacity Value9.2.167 SSB Index9.2.168 NR Carrier List9.2.169 SSB Positions In Burst9.2.170 NPRACH Configuration9.2.171 UE Radio Capability ID9.2.172 QoS Mapping Information9.2.173 UE Radio Capability9.2.174 URI9.2.175 SFN Offset9.2.176 Global RAN Node ID9.2.177 SCG UE History Information9.2.178 SCG Activation Status9.2.179 SCG Activation Request9.2.180 Served Cell Specific Info Request9.2.181 Security Indication9.2.182 Security Result9.2.183 Sensor Measurement Configuration9.3 Message and Information Element Abstract Syntax (with ASN.1)9.3.1 General9.3.2 Usage of Private Message Mechanism for Non-standard Use9.3.3 Elementary Procedure Definitions9.3.4 PDU Definitions9.3.5 Information Element definitions9.3.6 Common definitions9.3.7 Constant definitions9.3.8 Container definitions9.4 Message transfer syntax9.5 Timers10 Handling of unknown, unforeseen and erroneous protocol data 9.2.57 Void 36.4233GPPEvolved Universal Terrestrial Radio Access Network (E-UTRAN)Release 17TSX2 Application Protocol (X2AP) Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM