Message Types

RRC (Radio Resource Control)

  • RRCSetupRequest: Sent by the UE to initiate the setup of an RRC connection.

  • RRCSetup: Sent by the gNB to the UE to proceed with the RRC connection setup.

  • RRCSetupComplete: Sent by the UE to the gNB to indicate that the RRC connection setup is complete.

  • RRCConnectionReconfiguration: Sent by the gNB to modify an existing RRC connection (e.g., for handovers, bearer setup).

  • RRCConnectionReconfigurationComplete: Sent by the UE to acknowledge the RRCConnectionReconfiguration message.

  • RRCConnectionReconfigurationFailure: Sent by the UE to indicate that the reconfiguration failed.

  • RRCConnectionRelease: Sent by the gNB to release an established RRC connection.

  • RRCConnectionReleaseComplete: Sent by the UE to confirm the release of the RRC connection.

  • RRCConnectionReject: Sent by the gNB to reject an RRC connection request.

  • RRCConnectionSetupFailure: Sent by the UE to indicate that the setup process failed.

NAS (Non-Access Stratum)

  • AttachRequest: Sent by the UE to attach to the network.

  • AttachAccept: Sent by the core network to accept the attach request.

  • AttachReject: Sent by the core network to reject the attach request.

  • AuthenticationRequest: Sent by the core network to initiate authentication.

  • AuthenticationResponse: Sent by the UE in response to the authentication request.

  • SessionRequest: Sent by the UE to establish a session.

  • SessionAccept: Sent by the core network to accept the session establishment.

  • SessionReject: Sent by the core network to reject the session request.

  • ServiceRequest: Sent by the UE to request a service (e.g., voice or data services).

  • ServiceAccept: Sent by the core network to accept the service request.

  • ServiceReject: Sent by the core network to reject the service request.

  • BearerResourceCommand: Sent by the core network to modify bearer resources.

  • BearerResourceModifyResponse: Sent by the UE in response to bearer resource modification.

  • BearerResourceModifyRequest: Sent by the UE to request bearer resource modification.

  • BearerResourceReleaseCommand: Sent by the core network to release bearer resources.

  • BearerResourceReleaseResponse: Sent by the UE to acknowledge bearer resource release.

MAC (Medium Access Control)

  • Scheduling Request: Sent by the UE to request uplink resources.

  • Downlink Control Information (DCI): Sent by the gNB to provide scheduling information for downlink/uplink data.

  • Uplink Data: User data sent by the UE to the gNB.

  • Downlink Data: User data sent by the gNB to the UE.

PDCP (Packet Data Convergence Protocol)

  • Data: Carries user data between the UE and gNB, including security and header compression.

  • Status Report: Reports on the status of data delivery.

Physical Layer Messages

  • PDCCH (Physical Downlink Control Channel): Carries control information for scheduling downlink/uplink resources.

  • PDSCH (Physical Downlink Shared Channel): Carries user data in the downlink direction.

  • PUCCH (Physical Uplink Control Channel): Carries control information in the uplink direction.

  • PUSCH (Physical Uplink Shared Channel): Carries user data in the uplink direction.

Handover Messages

  • HandoverRequest: Sent by the target gNB to the source gNB to request handover information.

  • HandoverRequestAcknowledge: Sent by the source gNB to the target gNB with the necessary handover information.

  • HandoverCommand: Sent by the target gNB to the UE to initiate the handover process.

  • HandoverPreparation: Sent by the UE to the target gNB to acknowledge the handover command.

  • HandoverComplete: Sent by the UE to the target gNB to confirm successful handover.