In what condition will UE send message RRCSystemInfoRequest to network?

Specs & Protocol Testing
1

Hello NR Experts.

Iin what condition will UE send message RRCSystemInfoRequest to network?

Has anyone seen this message?

RRCSystemInfoRequest

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2

In 5G networks, a UE (User Equipment) typically sends an RRC (Radio Resource Control) System Information Request message to the network under various circumstances, such as : Initial Access , HAndover, Cell Reselection , Loss of System Information , Recovery after network issues etc.

3

A UE will send the RRCSystemInfoRequest message to the network in 5G under the following conditions:

  • Initial access: When a UE first attaches to a 5G NR network, it will send an RRCSystemInfoRequest message to request the system information that it needs to operate in the network. This includes information such as the available frequency bands, the cell ID, and the synchronization signals.
  • Handover: When a UE moves from one cell to another, it will send an RRCSystemInfoRequest message to the new cell to request the system information that it needs to operate in the new cell.
  • Reestablishment: When a UE reestablishes a connection to the network after a period of inactivity, it will send an RRCSystemInfoRequest message to request the system information that it needs to operate in the network.
  • Measurement report: When a UE sends a measurement report to the network, it may also include an RRCSystemInfoRequest message to request updated system information.

The RRCSystemInfoRequest message is a way for the UE to request the system information that it needs to operate in the network. The network will respond to the RRCSystemInfoRequest message with an RRCSystemInfo message, which contains the requested system information.

In addition to the above conditions, a UE may also send an RRCSystemInfoRequest message in the following cases:

  • When the UE detects a change in the network conditions.
  • When the UE is requested to do so by the network.

The RRCSystemInfoRequest message is an important part of the NR air interface. It allows the UE to obtain the system information that it needs to operate in the network.

4

Can the UE not get all these info from MIB/SIB or these are specific info that can only be gotten with RRCSystemInfoRequest ?