Messages / By Spec

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3GPP TS 24.301

NAS LTE

LTE Activate Dedicated EPS Bearer Context Accept

Activate Dedicated EPS Bearer Context Accept is the EPS session-management message the UE sends to confirm that the dedicated bearer requested by the network was accepted and activated successfully.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Activate Dedicated EPS Bearer Context Reject

Activate Dedicated EPS Bearer Context Reject is the LTE NAS message the UE sends when it cannot accept the dedicated bearer the network tried to activate.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Activate Dedicated EPS Bearer Context Request

Activate Dedicated EPS Bearer Context Request is the EPS session-management message the network sends when it wants the UE to activate a dedicated bearer linked to an already active default bearer.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Activate Default EPS Bearer Context Accept

Activate Default EPS Bearer Context Accept is the EPS session-management message the UE sends to confirm that the default bearer requested by the network was accepted and activated.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Activate Default EPS Bearer Context Reject

Activate Default EPS Bearer Context Reject is the LTE NAS message the UE sends when it cannot accept the default bearer the network tried to activate.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Activate Default EPS Bearer Context Request

Activate Default EPS Bearer Context Request is the EPS session-management message the network sends to the UE when it wants to activate the default bearer for a PDN connection.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Attach Accept

Attach Accept is the EPS NAS message the MME uses to grant LTE attach and deliver the accepted EPS mobility context to the UE.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Attach Complete

Attach Complete is the EPS NAS message the UE sends after Attach Accept to confirm that the granted attach context was received and processed.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Attach Reject

Attach Reject is the EPS NAS message the network sends when the corresponding LTE attach request is not accepted.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Attach Request

Attach Request is the EPS NAS message the UE uses to start the LTE attach procedure and ask the network to create EPS mobility-management context.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Authentication Failure

Authentication Failure is the EPS NAS message the UE sends when it cannot accept or complete the LTE/EPS authentication challenge normally.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Authentication Reject

Authentication Reject is the EPS NAS message the network sends when the LTE/EPS authentication attempt is not accepted and the current procedure cannot continue.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Authentication Request

Authentication Request is the EPS NAS message the MME uses to challenge the UE during EPS NAS authentication and verify the subscriber before later security and mobility procedures continue.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Authentication Response

Authentication Response is the EPS NAS message the UE sends after Authentication Request to return the calculated response parameter and let EPS authentication continue.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Bearer Resource Allocation Reject

Bearer Resource Allocation Reject is the LTE NAS message the network sends when it refuses the UE's request for a dedicated bearer resource.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Bearer Resource Allocation Request

Bearer Resource Allocation Request is the LTE NAS message the UE sends when it wants the network to allocate a dedicated bearer resource for an active PDN connection.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Bearer Resource Modification Reject

Bearer Resource Modification Reject is the LTE NAS message the network sends when it refuses the UE's request to modify an existing bearer resource.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Bearer Resource Modification Request

Bearer Resource Modification Request is the LTE NAS message the UE sends when it wants to change QoS or traffic-flow settings for an existing dedicated bearer resource.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Control Plane Service Request

Control Plane Service Request is the LTE NAS message the UE sends when service restoration uses control-plane CIoT EPS optimization instead of the normal user-plane service request path.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE CS Service Notification

CS Service Notification is the LTE NAS message the network sends when it needs to notify the UE about an incoming CS-related service branch such as CS fallback.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Deactivate EPS Bearer Context Accept

Deactivate EPS Bearer Context Accept is the LTE NAS message the UE sends after it released the bearer the network asked it to deactivate.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Deactivate EPS Bearer Context Request

Deactivate EPS Bearer Context Request is the EPS session-management message the network sends when it wants the UE to release a default or dedicated bearer context that is no longer needed.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Detach Accept

Detach Accept is the EPS NAS message used to confirm that the detach procedure has been completed, either as the network response to a UE-originated detach or as the UE response to a network-initiated detach.

MME -> UE or UE -> MME 3GPP TS 24.301
NAS LTE

LTE Detach Request

Detach Request is the EPS NAS message used to release EPS mobility-management context, either when the UE starts detach itself or when the network orders the UE to detach.

UE -> MME or MME -> UE 3GPP TS 24.301
NAS LTE

LTE Downlink Generic NAS Transport

Downlink Generic NAS Transport is the LTE NAS message the network sends when it needs to carry a generic payload through the EMM layer.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Downlink NAS Transport

Downlink NAS Transport is the EPS mobility-management message the network sends to carry an encapsulated SMS NAS payload toward the UE over LTE NAS signaling.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE EMM Information

EMM Information is the EPS mobility-management message the network sends when it wants to deliver operator display names, time zone information, or related informational context to the UE during an established EMM context.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE EMM Status

EMM Status is the LTE NAS message used to report an EMM protocol error, invalid state, or message-format problem back to the peer.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE ESM Data Transport

ESM Data Transport is the LTE NAS message used to carry small user data through the control plane when control-plane CIoT EPS optimization is in use.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE ESM Dummy Message

ESM Dummy Message is the LTE NAS session-management message used as a minimal protected ESM payload in specific control-plane or procedure-maintenance branches.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE ESM Information Request

ESM Information Request is the LTE NAS session-management message the network sends when it needs protected APN or protocol configuration details before completing PDN handling.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE ESM Information Response

ESM Information Response is the LTE NAS session-management message the UE sends to return APN or protocol configuration detail after ESM Information Request.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE ESM Status

ESM Status is the LTE NAS message used to report an ESM protocol error, invalid state, or malformed session-management message.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Extended Service Request

Extended Service Request is the EPS NAS message the UE sends when the service request procedure needs the extended LTE NAS form, especially for CS fallback, 1xCS fallback, or packet services via S1.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE GUTI Reallocation Command

GUTI Reallocation Command is the LTE NAS message the MME sends when it wants the UE to replace its current GUTI with a newly allocated identity.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE GUTI Reallocation Complete

GUTI Reallocation Complete is the LTE NAS message the UE sends to confirm that it accepted and stored the new GUTI.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Identity Request

Identity Request is the EPS NAS message the MME sends when it needs the UE to provide a specific identity before the NAS procedure can continue.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Identity Response

Identity Response is the EPS NAS message the UE sends after Identity Request to return the specific identity the MME asked for so the LTE NAS procedure can continue.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Modify EPS Bearer Context Accept

Modify EPS Bearer Context Accept is the LTE NAS message the UE sends after it applied the bearer update requested by the network.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Modify EPS Bearer Context Reject

Modify EPS Bearer Context Reject is the LTE NAS message the UE sends when it cannot accept a bearer modification proposed by the network.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Modify EPS Bearer Context Request

Modify EPS Bearer Context Request is the LTE NAS message the network sends when it wants to change bearer parameters that are already active on the UE.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Notification

Notification is the LTE NAS message the network sends when it needs to inform the UE about a specific NAS-side event that affects later handling.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE PDN Connectivity Request

PDN Connectivity Request is the EPS session-management message the UE sends when it wants connectivity to a PDN, either during attach or later as a standalone LTE NAS session request.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE PDN Disconnect Reject

PDN Disconnect Reject is the LTE NAS session-management message the network sends when it refuses the UE's request to release a PDN connection.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE PDN Disconnect Request

PDN Disconnect Request is the LTE NAS session-management message the UE sends when it wants to release one PDN connection and its associated default bearer.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Remote UE Report

Remote UE Report is the LTE NAS message used in remote UE or CIoT handling to report remote-device status or event information toward the network.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Remote UE Report Response

Remote UE Report Response is the LTE NAS message the network sends after it processes a Remote UE Report.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Security Mode Command

Security Mode Command is the EPS NAS message the MME sends to activate the selected NAS security algorithms and move the LTE/EPS procedure into protected signaling.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Security Mode Complete

Security Mode Complete is the EPS NAS message the UE sends to confirm that it accepted the selected NAS security algorithms and has switched into the commanded protected state.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Security Mode Reject

Security Mode Reject is the EPS NAS message the UE sends when it cannot accept the NAS security configuration selected by the MME in Security Mode Command.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Service Accept

Service Accept is the EPS NAS message the network sends when the service request procedure is accepted and active service can continue using the existing EPS context.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Service Reject

Service Reject is the EPS NAS message the network sends when the service request procedure is not accepted.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Service Request

Service Request is the EPS NAS message the UE uses to restore a NAS signaling connection and re-establish radio and S1 bearers while valid EPS context already exists.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Tracking Area Update Accept

Tracking Area Update Accept is the EPS NAS message the MME uses to accept the tracking area updating procedure and return the updated EPS mobility context to the UE.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Tracking Area Update Complete

Tracking Area Update Complete is the EPS NAS message the UE sends after Tracking Area Update Accept when the accepted TAU branch requires explicit UE completion.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Tracking Area Update Reject

Tracking Area Update Reject is the EPS NAS message the network sends when the tracking area updating procedure is not accepted.

MME -> UE 3GPP TS 24.301
NAS LTE

LTE Tracking Area Update Request

Tracking Area Update Request is the EPS NAS message the UE uses to update the network about tracking-area change, periodic presence, or related EPS mobility-context refresh.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Uplink Generic NAS Transport

Uplink Generic NAS Transport is the LTE NAS message the UE sends when it needs to carry a generic payload through the EMM transport branch.

UE -> MME 3GPP TS 24.301
NAS LTE

LTE Uplink NAS Transport

Uplink NAS Transport is the EPS mobility-management message the UE sends to carry an encapsulated SMS NAS payload toward the network over LTE NAS signaling.

UE -> MME 3GPP TS 24.301

3GPP TS 24.501

NAS 5G

5G NAS - 5GSM Status

5GSM Status is the 5GSM message used by both the UE and the network to report protocol errors or invalid session-management conditions for an active PDU session.

UE -> SMF via AMF / SMF -> UE via AMF 3GPP TS 24.501
NAS 5G

5G NAS - Authentication Failure

Authentication Failure is the UE's NAS message indicating that it could not validate or complete the network authentication challenge.

UE -> AMF 3GPP TS 24.501
NAS 5G

5G NAS - Authentication Reject

Authentication Reject is the NAS message the network sends when the UE's authentication attempt is not accepted and the current 5GMM path must stop.

AMF -> UE 3GPP TS 24.501
NAS 5G

5G NAS - Authentication Request

Authentication Request is the NAS message the AMF uses to challenge the UE and start the 5G primary authentication procedure.

AMF -> UE 3GPP TS 24.501
NAS 5G

5G NAS - Authentication Response

Authentication Response is the UE's NAS reply to Authentication Request, carrying the computed response or EAP data needed for subscriber verification.

UE -> AMF 3GPP TS 24.501
NAS 5G

5G NAS - Authentication Result

Authentication Result is the NAS message used to transport the final EAP authentication result from the network to the UE.

AMF -> UE 3GPP TS 24.501
NAS 5G

5G NAS - Configuration Update Command

Configuration Update Command is the network-initiated NAS message used to update UE 5GMM context after registration.

AMF -> UE 3GPP TS 24.501
NAS 5G

5G NAS - Configuration Update Complete

Configuration Update Complete is the UE's NAS acknowledgement that a network-initiated configuration update was received and applied.

UE -> AMF 3GPP TS 24.501
NAS 5G

5G NAS - Control Plane Service Request

Control Plane Service Request is the NAS message used when the UE requests control-plane service handling without the normal user-plane service path.

UE -> AMF 3GPP TS 24.501
NAS 5G

5G NAS - Deregistration Accept (UE Originating)

Deregistration Accept (UE Originating) is the AMF response confirming that the UE-originated deregistration request was accepted.

AMF -> UE 3GPP TS 24.501
NAS 5G

5G NAS - Deregistration Accept (UE Terminated)

Deregistration Accept (UE Terminated) is the UE response confirming that a network-initiated deregistration request was received and accepted.

UE -> AMF 3GPP TS 24.501
NAS 5G

5G NAS - Deregistration Request (UE Originating)

Deregistration Request (UE Originating) is the NAS message the UE sends when it wants to deregister from the 5GS.

UE -> AMF 3GPP TS 24.501
NAS 5G

5G NAS - Deregistration Request (UE Terminated)

Deregistration Request (UE Terminated) is the AMF-to-UE NAS message used when the network initiates deregistration.

AMF -> UE 3GPP TS 24.501
NAS 5G

5G NAS - DL NAS Transport

DL NAS Transport is the NAS wrapper message the network uses to deliver a payload downward to the UE when the procedure needs to carry additional content transparently through NAS.

AMF -> UE 3GPP TS 24.501
NAS 5G

5G NAS - Identity Request

Identity Request is the NAS message the network sends when it needs the UE to provide a specific identity such as SUCI, 5G-GUTI-related context, IMEI, IMEISV, or other identity information.

AMF -> UE 3GPP TS 24.501
NAS 5G

5G NAS - Identity Response

Identity Response is the NAS message the UE sends after Identity Request to provide the specific identity type the network asked for, such as SUCI, IMEI, IMEISV, or another requested identifier.

UE -> AMF 3GPP TS 24.501
NAS 5G

5G NAS - Network Slice-Specific Authentication Command

Network Slice-Specific Authentication Command is the NAS message the network uses to start slice-specific authentication for a requested S-NSSAI.

AMF -> UE 3GPP TS 24.501
NAS 5G

5G NAS - Network Slice-Specific Authentication Complete

Network Slice-Specific Authentication Complete is the UE's response carrying the slice-specific authentication reply for the requested S-NSSAI.

UE -> AMF 3GPP TS 24.501
NAS 5G

5G NAS - Network Slice-Specific Authentication Result

Network Slice-Specific Authentication Result is the NAS message carrying the final outcome of slice-specific authentication for a requested S-NSSAI.

AMF -> UE 3GPP TS 24.501
NAS 5G

5G NAS - Notification

Notification is the NAS message the network sends to inform the UE about an event that requires the UE's attention in the current mobility-management context.

AMF -> UE 3GPP TS 24.501
NAS 5G

5G NAS - Notification Response

Notification Response is the NAS message the UE sends after receiving Notification from the network to acknowledge the NAS indication and let the protected procedure continue.

UE -> AMF 3GPP TS 24.501
NAS 5G

5G NAS - PDU Session Authentication Command

PDU Session Authentication Command is the 5GSM message that carries an EAP request from the SMF to the UE when session-level authentication or authorization is required.

SMF -> UE via AMF 3GPP TS 24.501
NAS 5G

5G NAS - PDU Session Authentication Complete

PDU Session Authentication Complete is the 5GSM message the UE sends in response to PDU Session Authentication Command to carry the EAP response and continue the session-authentication exchange.

UE -> SMF via AMF 3GPP TS 24.501
NAS 5G

5G NAS - PDU Session Authentication Result

PDU Session Authentication Result is the 5GSM message the SMF sends to indicate a successful outcome of PDU session authentication, and it can also carry an EAP-success when external DN authentication is used.

SMF -> UE via AMF 3GPP TS 24.501
NAS 5G

5G NAS - PDU Session Establishment Accept

PDU Session Establishment Accept is the 5GSM success message the network sends after it creates the requested PDU session and returns the final session parameters, address, and QoS context.

SMF -> UE via AMF 3GPP TS 24.501
NAS 5G

5G NAS - PDU Session Establishment Reject

PDU Session Establishment Reject is the 5GSM failure response the network sends when the requested PDU session cannot be created and the UE needs the rejection reason.

SMF -> UE via AMF 3GPP TS 24.501
NAS 5G

5G NAS - PDU Session Establishment Request

PDU Session Establishment Request is the 5GSM message the UE sends to request creation of a new PDU session for user-plane connectivity toward a DNN on a selected slice.

UE -> SMF via AMF 3GPP TS 24.501
NAS 5G

5G NAS - PDU Session Modification Command

PDU Session Modification Command is the 5GSM message the network sends to tell the UE how an active PDU session should be updated after the modification request is accepted or when the network itself is changing the session.

SMF -> UE via AMF 3GPP TS 24.501
NAS 5G

5G NAS - PDU Session Modification Command Reject

PDU Session Modification Command Reject is the 5GSM message the UE sends when it cannot accept the network's modification command for an active PDU session.

UE -> SMF via AMF 3GPP TS 24.501
NAS 5G

5G NAS - PDU Session Modification Complete

PDU Session Modification Complete is the 5GSM message the UE sends after it applies the network-approved changes to an active PDU session.

UE -> SMF via AMF 3GPP TS 24.501
NAS 5G

5G NAS - PDU Session Modification Reject

PDU Session Modification Reject is the 5GSM failure response the network sends when a UE-requested change to an active PDU session cannot be accepted.

SMF -> UE via AMF 3GPP TS 24.501
NAS 5G

5G NAS - PDU Session Modification Request

PDU Session Modification Request is the 5GSM message the UE sends to change an already active PDU session, such as updating QoS, packet-filter behavior, header-compression settings, or other session parameters.

UE -> SMF via AMF 3GPP TS 24.501
NAS 5G

5G NAS - PDU Session Release Command

PDU Session Release Command is the 5GSM message the network sends to tell the UE that an active PDU session is being released and to provide any release-related cause or retry guidance.

SMF -> UE via AMF 3GPP TS 24.501
NAS 5G

5G NAS - PDU Session Release Complete

PDU Session Release Complete is the 5GSM message the UE sends after it receives a release command and considers the active PDU session released.

UE -> SMF via AMF 3GPP TS 24.501
NAS 5G

5G NAS - PDU Session Release Reject

PDU Session Release Reject is the 5GSM failure response the network sends when it does not accept the UE's request to release an active PDU session.

SMF -> UE via AMF 3GPP TS 24.501
NAS 5G

5G NAS - PDU Session Release Request

PDU Session Release Request is the 5GSM message the UE sends when it wants to end an already active PDU session, or when it needs to release the session because of a local protocol or service condition.

UE -> SMF via AMF 3GPP TS 24.501
NAS 5G

5G NAS - Registration Accept

Registration Accept is the 5GMM message the AMF sends when it accepts UE registration and returns the mobility, security, and reachability context the UE needs to operate in the 5GS.

AMF -> UE 3GPP TS 24.501
NAS 5G

5G NAS - Registration Complete

Registration Complete is the UE-to-AMF NAS message used to confirm that the UE has accepted the registration context returned by the network.

UE -> AMF 3GPP TS 24.501
NAS 5G

5G NAS - Registration Reject

Registration Reject is the NAS message the AMF sends when a 5G registration attempt is refused and the UE must stop the current registration path.

AMF -> UE 3GPP TS 24.501
NAS 5G

5G NAS - Registration Request

Starts a 5G registration or mobility update by sending UE identity and registration intent to the core.

UE -> AMF 3GPP TS 24.501
NAS 5G

5G NAS - Relay Authentication Request

Relay Authentication Request is the NAS message the network sends to start or continue the relay-specific authentication branch after relay-key handling or related relay security preparation.

Network -> UE 3GPP TS 24.501
NAS 5G

5G NAS - Relay Authentication Response

Relay Authentication Response is the NAS message the UE or relay participant sends back after Relay Authentication Request to return the relay-specific authentication result information.

UE -> network 3GPP TS 24.501
NAS 5G

5G NAS - Relay Key Accept

Relay Key Accept is the NAS message the network sends when the relay key request succeeds and the relay-related key response material can be delivered to the UE.

Network -> UE 3GPP TS 24.501
NAS 5G

5G NAS - Relay Key Reject

Relay Key Reject is the NAS message the network sends when the relay key request cannot be accepted and the relay-related key procedure must stop or take a failure branch.

Network -> UE 3GPP TS 24.501
NAS 5G

5G NAS - Relay Key Request

Relay Key Request is the NAS message used to request relay-related keying material so the relay security procedure can continue in a 5G relay or ProSe relay context.

UE -> network 3GPP TS 24.501
NAS 5G

5G NAS - Remote UE Report

Remote UE Report is the 5GSM message the relay UE sends to inform the network that one or more 5G ProSe remote UEs connected or disconnected through the relay.

UE -> SMF via AMF 3GPP TS 24.501
NAS 5G

5G NAS - Remote UE Report Response

Remote UE Report Response is the 5GSM acknowledgement sent back to the relay UE after the SMF processes a Remote UE Report.

SMF -> UE via AMF 3GPP TS 24.501
NAS 5G

5G NAS - Security Mode Command

Security Mode Command is the NAS message the AMF sends to activate the selected NAS security algorithms and move the 5GMM procedure into a protected signaling state.

AMF -> UE 3GPP TS 24.501
NAS 5G

5G NAS - Security Mode Complete

Security Mode Complete is the NAS message the UE sends to confirm that it accepted the selected NAS security algorithms and has switched into the commanded protected signaling state.

UE -> AMF 3GPP TS 24.501
NAS 5G

5G NAS - Security Mode Reject

Security Mode Reject is the NAS message the UE sends when it cannot accept the NAS security configuration selected by the AMF in Security Mode Command.

UE -> AMF 3GPP TS 24.501
NAS 5G

5G NAS - Service Accept

Service Accept is the NAS message confirming that the network accepted the UE's service request and that active service can continue.

AMF -> UE 3GPP TS 24.501
NAS 5G

5G NAS - Service Reject

Service Reject is the NAS message the network sends when a service request is refused even though the UE already has registration context.

AMF -> UE 3GPP TS 24.501
NAS 5G

5G NAS - Service Request

Service Request is the NAS message the UE uses to request service resumption when it already has a valid registration context but needs active signaling again.

UE -> AMF 3GPP TS 24.501
NAS 5G

5G NAS - Service-level Authentication Command

Service-level Authentication Command is the 5GSM message the SMF sends to deliver service-level authentication and authorization payload to the UE.

SMF -> UE via AMF 3GPP TS 24.501
NAS 5G

5G NAS - Service-level Authentication Complete

Service-level Authentication Complete is the 5GSM message the UE sends in response to Service-level Authentication Command and uses to return the service-level AA payload or response.

UE -> SMF via AMF 3GPP TS 24.501
NAS 5G

5G NAS - UL NAS Transport

UL NAS Transport is the NAS wrapper message the UE uses to send a payload upward toward the core when the NAS procedure needs to carry additional information transparently.

UE -> AMF 3GPP TS 24.501

3GPP TS 36.331

LTE RRC LTE

LTE RRC Connection Reconfiguration

Downlink LTE RRC message used to modify radio configuration, measurements, mobility behavior, bearer settings, and connected-mode control after setup.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC Connection Reconfiguration Complete

Uplink LTE RRC message sent by the UE to confirm successful handling of RRCConnectionReconfiguration.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC Connection Reestablishment

Downlink LTE RRC message sent by the network to accept re-establishment and rebuild the connected signaling context after a recoverable failure.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC Connection Reestablishment Complete

Uplink LTE RRC message sent by the UE to confirm that re-establishment recovery was completed successfully.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC Connection Reestablishment Reject

Downlink LTE RRC message sent by the network when the re-establishment attempt is not accepted.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC Connection Reestablishment Request

Uplink LTE RRC message sent by the UE to request re-establishment after radio link failure, handover failure, or other re-establishment-eligible failure conditions.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC Connection Reject

Downlink LTE RRC message sent by the eNodeB when a fresh RRC connection establishment attempt is not accepted.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC Connection Release

Downlink LTE RRC message used to release the connected RRC context and move the UE back toward idle-mode behavior or redirection handling.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC Connection Request

Uplink LTE RRC message sent by the UE on SRB0 and UL-CCCH to request establishment of an RRC connection.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC Connection Resume Complete-r13

Uplink LTE RRC message sent by the UE to confirm that the resume branch completed successfully and the suspended context was restored.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC Connection Resume Request-r13

Uplink LTE RRC message sent by the UE to request continuation of a suspended LTE context without starting a full fresh connection setup.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC Connection Resume-r13

Downlink LTE RRC message sent by the eNodeB to resume a suspended LTE connection context without starting a full fresh connection setup.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC Connection Setup

Downlink LTE RRC message sent by the eNodeB to establish SRB1 and move the UE into connected-mode signaling.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC Connection Setup Complete

Uplink LTE RRC message sent by the UE after applying RRCConnectionSetup to confirm setup completion and carry the initial dedicated NAS message.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC Counter Check

Downlink LTE RRC message used by the eNodeB to ask the UE to verify PDCP COUNT synchronization for one or more DRBs.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC Counter Check Response

Uplink LTE RRC message used by the UE to reply to Counter Check and confirm the outcome of the PDCP COUNT verification step.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC CSFB Parameters Request CDMA2000

Downlink LTE RRC message used to request cdma2000-related CS fallback parameter handling from the UE.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC CSFB Parameters Response CDMA2000

Uplink LTE RRC message used by the UE to return cdma2000 CS fallback parameters requested by the network.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC DL Dedicated Message Segment-r16

Downlink LTE RRC segmentation container used when a dedicated LTE RRC message is split across multiple fragments.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC DL Information Transfer

Downlink LTE RRC message used by the eNodeB to carry NAS payloads toward the UE over the LTE access stratum.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC Early Data Complete-r15

Downlink LTE RRC message used to complete the control-plane early data transmission branch.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC Early Data Request-r15

Uplink LTE RRC message used by the UE to request control-plane early data transmission.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC Failure Information r15

Uplink LTE RRC message used by the UE to report release-specific failure information back to the network.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC Failure Information r16

Uplink LTE RRC message used by the UE to return release 16 failure information to the network.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC Handover From EUTRA Preparation Request

Downlink LTE RRC message used when the source E-UTRA side starts handover preparation toward cdma2000.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC InDeviceCoex Indication r11

Uplink LTE RRC message used by the UE to report in-device coexistence constraints that affect LTE radio operation.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC InterFreqRSTD Measurement Indication r10

Uplink LTE RRC message used by the UE to indicate status around inter-frequency RSTD measurement handling for positioning-related procedures.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC Logged Measurement Configuration-r10

Downlink LTE RRC message used to configure logged measurement collection for MDT-related behavior.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC MBMS Counting Request r10

Downlink LTE RRC message used by the network to request MBMS counting responses from interested UEs.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC MBMS Counting Response r10

Uplink LTE RRC message used by the UE to answer an MBMS counting request.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC MBMS Interest Indication r11

Uplink LTE RRC message used by the UE to report MBMS interest information to the network.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC MBSFN Area Configuration r9

Downlink LTE RRC message used to deliver MBSFN area configuration to the UE.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC MCG Failure Information r16

Uplink LTE RRC message used by the UE to report master cell group failure information.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC MeasReportAppLayer r15

Uplink LTE RRC message used by the UE to report configured application-layer measurement results to the network.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC Measurement Report

Uplink LTE RRC message sent by the UE when configured measurement conditions are met so the network can make mobility and radio-control decisions.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC MIB - Master Information Block

Broadcast LTE RRC message on BCH that gives the UE the first essential cell-wide radio context needed to continue system-information acquisition toward SIB1 and later access behavior.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC MIB MBMS r14

Broadcast LTE RRC message carrying the MBMS-specific master information block for MBMS-oriented operation.

Broadcast 3GPP TS 36.331
LTE RRC LTE

LTE RRC Mobility From EUTRA Command

Downlink LTE RRC message used to command mobility away from the current E-UTRA connection toward another RAT or a cell change order outcome.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC Paging

Downlink LTE RRC message used to notify an idle UE that the network needs its attention for service, signaling, system information change, or warning-related behavior.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC Proximity Indication r9

Uplink LTE RRC message used by the UE to report proximity-related status relevant to network-controlled proximity services handling.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC PUR Configuration Request r16

Downlink LTE RRC message used to request or deliver PUR-related configuration handling.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC RN Reconfiguration Complete-r10

Uplink LTE RRC message used by the relay node to acknowledge RNReconfiguration-r10.

RN -> Donor eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC RN Reconfiguration-r10

Downlink LTE RRC message used by a donor eNodeB to change relay-node specific configuration.

Donor eNodeB -> RN 3GPP TS 36.331
LTE RRC LTE

LTE RRC SCG Failure Information NR r15

Uplink LTE RRC message used in E-UTRA master / NR secondary contexts when the UE reports failure affecting the NR-side secondary cell group.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC SCG Failure Information r12

Uplink LTE RRC message used by the UE to report secondary cell group failure in dual-connectivity related LTE contexts.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC SCPTM Configuration BR r14

Downlink LTE RRC message used to deliver SC-PTM configuration for bandwidth-reduced UE contexts.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC SCPTM Configuration r13

Downlink LTE RRC message used to deliver SC-PTM configuration to the UE.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC Security Mode Command

Downlink LTE RRC message sent by the eNodeB to activate access-stratum security for the UE.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC Security Mode Complete

Uplink LTE RRC message sent by the UE to confirm that SecurityModeCommand was accepted and LTE AS security activation succeeded.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC Security Mode Failure

Uplink LTE RRC message sent by the UE when it cannot continue with the received SecurityModeCommand.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC SIB1 - System Information Block Type 1

Broadcast LTE RRC message on BCCH and DL-SCH that gives the UE the essential access identity, cell selection, scheduling, and change-detection context needed before it can use the wider SIB set.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC SIB1 BR r13

Broadcast LTE RRC message carrying the first BR-specific system-information block.

Broadcast 3GPP TS 36.331
LTE RRC LTE

LTE RRC SIB1 MBMS r14

Broadcast LTE RRC message carrying the first MBMS-specific system-information block.

Broadcast 3GPP TS 36.331
LTE RRC LTE

LTE RRC SIB13 - System Information Block Type 13

Broadcast LTE RRC system information block carried inside System Information that provides MBMS and MBSFN area information used before MCCH reception.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC SIB2 - System Information Block Type 2

Broadcast LTE RRC system information block carried inside System Information that gives the UE the common radio, access barring, timer, and uplink-related context needed before normal LTE access can proceed.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC SIB3 - System Information Block Type 3

Broadcast LTE RRC system information block carried inside System Information that gives the UE the serving-frequency cell reselection rules used in idle mode after the common SIB1 and SIB2 context is already known.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC SIB4 - System Information Block Type 4

Broadcast LTE RRC system information block carried inside System Information that provides intra-frequency neighbor-cell detail used during idle-mode camping and same-frequency cell reselection.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC SIB5 - System Information Block Type 5

Broadcast LTE RRC system information block carried inside System Information that provides inter-frequency reselection information for other LTE carrier frequencies in idle mode.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC SIB6 - System Information Block Type 6

Broadcast LTE RRC system information block carried inside System Information that provides inter-RAT reselection information for UTRA frequencies and UTRA neighboring cells in idle mode.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC SIB7 - System Information Block Type 7

Broadcast LTE RRC system information block carried inside System Information that provides inter-RAT reselection information for GERAN frequencies in idle mode.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC SIB8 - System Information Block Type 8

Broadcast LTE RRC system information block carried inside System Information that provides inter-RAT reselection information for cdma2000 1xRTT and HRPD idle mobility.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC Sidelink UE Information r12

Uplink LTE RRC message used by the UE to report sidelink-related information to the network.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC System Information

Broadcast LTE RRC message on BCCH and DL-SCH that carries one or more SIBs such as SIB2 and later system-information blocks after the UE has already read MIB and SIB1.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC System Information BR r13

Broadcast LTE RRC message carrying bandwidth-reduced system information.

Broadcast 3GPP TS 36.331
LTE RRC LTE

LTE RRC System Information MBMS r14

Broadcast LTE RRC message carrying later MBMS-specific system information.

Broadcast 3GPP TS 36.331
LTE RRC LTE

LTE RRC UE Assistance Information r11

Uplink LTE RRC message used by the UE to provide assistance information the network can use for connected-mode optimization decisions.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC UE Capability Enquiry

Downlink LTE RRC message used by the eNodeB to request UE capability information before applying capability-dependent radio configuration.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC UE Capability Information

Uplink LTE RRC message used by the UE to report its capability information back to the eNodeB.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC UE Information Request r9

Downlink LTE RRC message used by the eNodeB to ask the UE for stored diagnostic information such as random access details or radio link failure context.

eNodeB -> UE 3GPP TS 36.331
LTE RRC LTE

LTE RRC UE Information Response r9

Uplink LTE RRC message used by the UE to return the diagnostic information requested by UEInformationRequest-r9, including random access details, radio link failure context, or both.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC UL Dedicated Message Segment-r16

Uplink LTE RRC segmentation container used when a UE dedicated LTE RRC message is sent in multiple fragments.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC UL Handover Preparation Transfer

Uplink LTE RRC message used by the UE to return cdma2000 handover preparation information to the source eNodeB.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC UL Information Transfer

Uplink LTE RRC message used by the UE to carry NAS payloads toward the network over the LTE access stratum.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC UL Information Transfer IRAT r16

Uplink LTE RRC message used to transfer dedicated information in inter-RAT related contexts.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC UL Information Transfer MRDC r15

Uplink LTE RRC message used to transfer dedicated information in MR-DC related contexts.

UE -> eNodeB 3GPP TS 36.331
LTE RRC LTE

LTE RRC WLAN Connection Status Report r13

Uplink LTE RRC message used by the UE to report WLAN connection status relevant to LTE and WLAN interworking handling.

UE -> eNodeB 3GPP TS 36.331

3GPP TS 38.331

RRC 5G

5G NR - Counter Check

Counter Check is the NR RRC message the network uses to provide current PDCP COUNT MSB values for configured DRBs and ask the UE to compare them with its own COUNT state.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - Counter Check Response

Counter Check Response is the NR RRC message the UE sends after Counter Check to return the compared DRB COUNT values for bearer-state verification.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - Dedicated SIB Request

Dedicated SIB Request is the UE-to-network NR RRC message used to request on-demand system information while the UE is already in connected mode.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - DL Dedicated Message Segment

DL Dedicated Message Segment is the NR downlink RRC segmentation container used when a dedicated RRC message is too large to send as a single unit.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - DL Information Transfer

DL Information Transfer is the NR RRC message the network uses to send upper-layer information, most commonly NAS messages, to the UE over the established RRC connection.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - DL Information Transfer MRDC

DL Information Transfer MRDC is the downlink NR RRC container used to deliver MR-DC-related information toward the UE.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - Failure Information

Failure Information is the NR RRC message the UE uses to inform the network that it has detected a failure, especially an RLC bearer failure associated with an MCG or SCG bearer.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - IAB Other Information

IAB Other Information is an NR RRC message used to deliver additional IAB-specific information needed by an IAB node.

gNB / donor -> IAB node 3GPP TS 38.331
RRC 5G

5G NR - Indirect Path Failure Information

Indirect Path Failure Information is an NR RRC message used to report failure related to an indirect path or relayed path in advanced deployment scenarios.

IAB node / UE -> donor / gNB 3GPP TS 38.331
RRC 5G

5G NR - Location Measurement Indication

Location Measurement Indication is the NR RRC message used by the UE to indicate location-related measurement information toward the network.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - Logged Measurement Configuration

Logged Measurement Configuration is the NR RRC message used to configure measurement logging behavior for MDT and later reporting workflows.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - Master Information Block (MIB)

The NR Master Information Block (MIB) is the first essential broadcast RRC information a UE decodes from PBCH after synchronization. It gives the UE the minimal system information needed to continue toward SIB1 acquisition and initial access.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - MBS Broadcast Configuration

MBS Broadcast Configuration is the NR RRC message used to provide UE-specific or dedicated MBS broadcast configuration.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - MBS Interest Indication

MBS Interest Indication is the UE-to-network NR RRC message used to indicate interest in MBS services or sessions.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - MBS Multicast Configuration

MBS Multicast Configuration is the NR RRC message used to provide dedicated MBS multicast configuration to the UE.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - MCG Failure Information

MCG Failure Information is the NR RRC message used by the UE to report failure related to the master cell group.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - Measurement Configuration

Measurement Configuration is the NR RRC configuration block that tells the UE what to measure, when to report, and how measurement identities map objects and report rules. It is usually delivered inside RRC Reconfiguration rather than as a standalone message.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - Measurement Report

Measurement Report is the NR RRC message a UE sends to the gNB when configured measurement conditions are met, allowing the network to make mobility, beam, and radio-resource decisions.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - Measurement Report AppLayer

Measurement Report AppLayer is the NR RRC message used by the UE to report application-layer measurements to the network.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - Mobility From NR Command

Mobility From NR Command is the NR RRC message used by the network to command mobility away from the current NR context toward another target system or mobility outcome.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - Paging

Paging is the NR RRC message used by the network to notify an idle-mode or inactive-mode UE that downlink signaling or service activity requires the UE's attention.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - RRC Reconfiguration

Reconfigures the UE radio connection after setup, including bearers, measurements, and mobility.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - RRC Reconfiguration Complete

RRC Reconfiguration Complete is the UE-to-network NR RRC message confirming that the UE successfully applied the received RRC Reconfiguration.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - RRC Reestablishment

RRC Reestablishment is the downlink NR RRC message the network sends when it accepts a reestablishment attempt and provides the recovered connected-mode context.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - RRC Reestablishment Complete

RRC Reestablishment Complete is the UE-to-network NR RRC message confirming that reestablishment succeeded and the recovered context is active.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - RRC Reestablishment Request

Uplink NR RRC message sent by the UE on SRB0 and CCCH to request re-establishment of an existing RRC connection after radio link failure, handover failure, or reconfiguration failure.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - RRC Reject

Downlink NR RRC message used by the network to reject an RRC connection establishment attempt or an RRC connection resumption attempt.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - RRC Release

RRC Release is the downlink NR RRC message used by the network to release the connected-mode context and move the UE out of active connected signaling.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - RRC Resume

RRC Resume is the downlink NR RRC message used by the network to resume a suspended or inactive context after a valid resume request.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - RRC Resume Complete

RRC Resume Complete is the UE-to-network NR RRC message confirming that the suspended or inactive context was resumed successfully.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - RRC Resume Request

RRC Resume Request is the UE-to-network NR RRC message used to request resumption of a suspended or inactive context.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - RRC Resume Request1

RRC Resume Request1 is an alternate NR RRC resume request message variant used in the resume procedure.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - RRC Setup

Downlink NR RRC message sent by the gNB to establish SRB1 and move the UE into the connected RRC procedure.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - RRC Setup Complete

Uplink NR RRC message sent by the UE on SRB1 and DCCH to confirm successful RRC connection establishment and transfer the initial NAS message.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - RRC Setup Request

Uplink NR RRC message sent by the UE on SRB0 and CCCH to request establishment of an RRC connection.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - RRC SystemInfo Request

RRC SystemInfo Request is the NR RRC message the UE uses to request system information directly from the network.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - SCG Failure Information

SCG Failure Information is the NR RRC message used by the UE to report failure related to the secondary cell group.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - SCG Failure Information EUTRA

SCG Failure Information EUTRA is the NR RRC message used to report failure in an E-UTRA secondary cell group context.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - Security Mode Command

Downlink NR RRC message used by the gNB to activate AS security for the UE in RRC_CONNECTED.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - Security Mode Complete

Uplink NR RRC message used by the UE to confirm successful activation of the selected AS security configuration.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - Security Mode Failure

Uplink NR RRC message used by the UE to indicate that the commanded AS security activation could not be completed successfully.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - Sidelink UE Information NR

Sidelink UE Information NR is the UE-to-network NR RRC message used to provide sidelink-related information toward the network.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - System Information

System Information is the NR RRC broadcast container used to carry one or more SIBs or positioning SIBs with the same periodicity.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 1 (SIB1)

SystemInformationBlockType1 (SIB1) is the key NR broadcast system information block that tells the UE how to access the cell, select PLMN context, and interpret important cell-level access restrictions and configuration.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 10 (SIB10)

System Information Block 10 (SIB10) is an NR broadcast system information block used to carry the Human-Readable Network Names (HRNN) of NPNs listed in SIB1.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 11 (SIB11)

System Information Block 11 (SIB11) is an NR broadcast system information block used to provide idle and inactive measurement configuration for the UE.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 12 (SIB12)

System Information Block 12 (SIB12) is an NR broadcast system information block used to provide sidelink communication and discovery configuration to UEs that support NR sidelink.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 13 (SIB13)

System Information Block 13 (SIB13) is an NR broadcast system information block used to provide V2X sidelink communication information aligned with the LTE SystemInformationBlockType21 behavior referenced by NR.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 14 (SIB14)

System Information Block 14 (SIB14) is an NR broadcast system information block used to provide information related to LTE SystemInformationBlockType26 for V2X sidelink communication.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 15 (SIB15)

System Information Block 15 (SIB15) is an NR broadcast system information block used to provide disaster roaming information for PLMNs sharing the cell.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 16 (SIB16)

System Information Block 16 (SIB16) is an NR broadcast system information block used to provide slice-based cell reselection information.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 17 (SIB17)

System Information Block 17 (SIB17) is an NR broadcast system information block used to provide TRS resource configuration for idle and inactive UEs.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 18 (SIB18)

System Information Block 18 (SIB18) is an NR broadcast system information block used to provide Group IDs for Network selection (GINs) to support credentials-holder based access and UE onboarding.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 19 (SIB19)

System Information Block 19 (SIB19) is an NR broadcast system information block used to provide NTN-specific parameters for the serving cell and, when present, neighboring NTN cells.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 2 (SIB2)

System Information Block 2 (SIB2) is an NR broadcast system information block used mainly for cell reselection and idle-state mobility-related behavior after the UE has already acquired the essential access information from MIB and SIB1.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 20 (SIB20)

System Information Block 20 (SIB20) is an NR broadcast system information block used to provide the MCCH and MTCH acquisition configuration for MBS broadcast.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 21 (SIB21)

System Information Block 21 (SIB21) is an NR broadcast system information block used to provide MBS Frequency Selection Area Identity mapping for service continuity.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 22 (SIB22)

System Information Block 22 (SIB22) is an NR broadcast system information block used to provide ATG-specific parameters for the serving cell and optionally neighboring cells.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 23 (SIB23)

System Information Block 23 (SIB23) is an NR broadcast system information block used to provide ranging and sidelink positioning information.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 24 (SIB24)

System Information Block 24 (SIB24) is an NR broadcast system information block used to provide the information required to acquire multicast MCCH and MTCH configuration.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 25 (SIB25)

System Information Block 25 (SIB25) is an NR broadcast system information block used to provide TN coverage information for NTN-related operation.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 3 (SIB3)

System Information Block 3 (SIB3) is an NR broadcast system information block used for intra-frequency cell reselection behavior and idle-state mobility decisions on the current NR carrier.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 4 (SIB4)

System Information Block 4 (SIB4) is an NR broadcast system information block used for inter-frequency cell reselection behavior and idle-state mobility decisions across other NR carrier frequencies.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 5 (SIB5)

System Information Block 5 (SIB5) is an NR broadcast system information block used for inter-RAT mobility context, helping the UE evaluate reselection toward other radio access technologies such as LTE.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 6 (SIB6)

System Information Block 6 (SIB6) is an NR broadcast system information block used for inter-RAT mobility context toward UTRA, helping the UE evaluate reselection from NR toward UMTS when that mobility path is part of the deployment.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 7 (SIB7)

System Information Block 7 (SIB7) is an NR broadcast system information block used for inter-RAT mobility context toward GERAN, helping the UE evaluate reselection from NR toward GSM where that legacy mobility path still exists.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 8 (SIB8)

System Information Block 8 (SIB8) is an NR broadcast system information block used for inter-RAT mobility context toward cdma2000 systems where that legacy mobility path still exists.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - System Information Block 9 (SIB9)

System Information Block 9 (SIB9) is an NR broadcast system information block used to convey time information such as UTC and GPS-related timing context to the UE.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - UE Assistance Information

UE Assistance Information is the UE-to-network NR RRC message used to provide assistance or preference information that helps the network optimize handling for the UE.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - UE Capability Enquiry

Downlink NR RRC message used by the gNB to request UE capability information needed for feature, bearer, mobility, and radio configuration decisions.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - UE Capability Information

Uplink NR RRC message used by the UE to report its supported radio capability containers to the gNB.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - UE Information Request

UE Information Request is the NR RRC message the network uses to ask the UE for diagnostic information such as radio link failure context, connection establishment failure context, logged measurements, mobility history, random access reports, or idle and inactive measurement information.

gNB -> UE 3GPP TS 38.331
RRC 5G

5G NR - UE Information Response

UE Information Response is the NR RRC message the UE uses to return requested diagnostic information such as RLF data, connection establishment failure data, logged measurements, mobility history, random access reports, or idle and inactive measurement information.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - UE Positioning Assistance Info

UE Positioning Assistance Info is the UE-to-network NR RRC message used to provide UE-side positioning assistance information.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - UL Dedicated Message Segment

UL Dedicated Message Segment is the uplink NR RRC segmentation container used when a UE dedicated RRC payload is too large to send as a single message.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - UL Information Transfer

UL Information Transfer is the NR RRC message the UE uses to send upper-layer information, most commonly NAS messages, to the network over the established RRC connection.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - UL Information Transfer IRAT

UL Information Transfer IRAT is the UE-to-network NR RRC wrapper used to carry inter-RAT related information in the uplink direction.

UE -> gNB 3GPP TS 38.331
RRC 5G

5G NR - UL Information Transfer MRDC

UL Information Transfer MRDC is the UE-to-network NR RRC wrapper used to carry MR-DC-related information in the uplink direction.

UE -> gNB 3GPP TS 38.331

3GPP TS 38.413

RFC 3261 / 3GPP TS 24.229

IMS 5G

IMS SIP 100 Trying

100 Trying confirms that the request was received and transaction processing has started.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 180 Ringing

180 Ringing shows that the terminating side is being alerted for the session request.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 181 Call Is Being Forwarded

181 Call Is Being Forwarded shows that the original target is redirecting or forwarding the session attempt.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 182 Queued

182 Queued shows that the request is waiting in a queue instead of progressing immediately.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 200 OK

200 OK confirms that the SIP request completed successfully.

UE <-> IMS network RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 302 Moved Temporarily

302 Moved Temporarily redirects the sender to another temporary target or contact.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 380 Alternative Service

380 Alternative Service indicates that the original request cannot be served as asked and suggests another service path.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 400 Bad Request

400 Bad Request means the request could not be understood or accepted because of syntax or structural problems.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 401 Unauthorized

401 Unauthorized challenges the request and asks the sender to retry with authentication.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 403 Forbidden

403 Forbidden means the request was understood but the network or service refused to allow it.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 404 Not Found

404 Not Found means the target user or service could not be found at the requested destination.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 405 Method Not Allowed

405 Method Not Allowed means the target exists but does not allow the SIP method that was used.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 406 Not Acceptable

406 Not Acceptable means the request was understood, but the target cannot satisfy the acceptable formats or features indicated.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 407 Proxy Authentication Required

407 Proxy Authentication Required challenges the sender to authenticate through a SIP proxy, commonly the P-CSCF path.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 408 Request Timeout

408 Request Timeout means the expected transaction progress did not happen in time.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 415 Unsupported Media Type

415 Unsupported Media Type means the target cannot process the request body in the format that was sent.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 480 Temporarily Unavailable

480 Temporarily Unavailable means the target is currently unreachable or unavailable, but not permanently unknown.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 481 Call or Transaction Does Not Exist

481 Call or Transaction Does Not Exist means the receiving side could not match the request to a valid dialog or transaction.

UE <-> IMS network RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 486 Busy Here

486 Busy Here means the target user is busy at the reached destination.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 487 Request Terminated

487 Request Terminated means the original request branch was stopped before normal completion.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 488 Not Acceptable Here

488 Not Acceptable Here means the request reached the target, but the local media or session offer cannot be accepted there.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 500 Server Internal Error

500 Server Internal Error means the server hit an internal problem while handling the request.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 503 Service Unavailable

503 Service Unavailable means the service cannot handle the request right now, usually for temporary server or overload reasons.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 504 Server Time-out

504 Server Time-out means a server did not get a timely answer from another server while handling the request.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 600 Busy Everywhere

600 Busy Everywhere means the request should not be retried elsewhere because the target is considered busy globally.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 603 Decline

603 Decline means the request was actively refused and should not be retried to other locations for the same attempt.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 604 Does Not Exist Anywhere

604 Does Not Exist Anywhere means the target does not exist globally for the request.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP 606 Not Acceptable

606 Not Acceptable means no acceptable target branch can satisfy the requested session or content constraints.

IMS network -> UE RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP ACK

ACK is the SIP request that confirms a final response to INVITE.

UE <-> IMS network RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP BYE

BYE is the SIP request that terminates an established dialog.

UE <-> IMS network RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP CANCEL

CANCEL is the SIP request that stops a pending INVITE transaction before final acceptance.

UE <-> IMS network RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP INVITE

INVITE is the SIP request that starts or modifies the main session dialog in IMS.

UE <-> IMS network RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP OPTIONS

OPTIONS is the SIP request used to query capabilities or liveness without creating a full session.

UE <-> IMS network RFC 3261 / 3GPP TS 24.229
IMS 5G

IMS SIP REGISTER

REGISTER is the SIP request that creates, refreshes, or removes IMS service reachability for the UE.

UE <-> IMS network RFC 3261 / 3GPP TS 24.229

RFC 3261 / RFC 3262 / 3GPP TS 24.229

RFC 3261 / RFC 3515 / 3GPP TS 24.229

RFC 3262 / 3GPP TS 24.229

RFC 3311 / 3GPP TS 24.229

RFC 3428 / 3GPP TS 24.229

RFC 3515 / 3GPP TS 24.229

RFC 3903 / 3GPP TS 24.229

RFC 6086 / 3GPP TS 24.229

RFC 6665 / 3GPP TS 24.229

RFC 8688 / 3GPP TS 24.229