Path Switch Request Setup Failed Transfer IE

For each PDU session resource with failed switching, NG-RAN includes Path Switch Request Setup Failed Transfer IE of the Path Switch Request message. This message includes the cause value, with the details on cause for the unsuccessful switching to Target NG-RAN.

Note

SMF supports only the decoding of N2 Cause IE.

The Path Switch Request Setup Failed Transfer IE includes the following causes and their cause values:

Path Switch Request Setup Failed Transfer IE Causes and Cause Values
Cause Cause Value

Description

Radio Network Layer

User Plane Security Enforcement

NG-RAN includes the following cause values in case the User Plane Security Enforcement information is unfulfilled. These cause values have either the Required or Preferred value:

  • UP integrity protection not possible

  • UP confidentiality protection not possible

  • UE maximum integrity protected data rate reason

  • Encryption and/or integrity protection algorithms not supported

Not Supported 5QI Value

NG-RAN includes this cause value when the Target NG-RAN accepts none of the QoS Flows of a PDU Session.

Slice not supported

NG-RAN includes the following cause values when the corresponding network slice isn't supported in the Target NG-RAN.

  • Slices not supported

  • Resources not available for the slices

Resource Unavailability

NG-RAN includes the following cause values when insufficient resources are available to switch in the Target NG-RAN.

  • No radio resources available in target cell

  • Radio resources not available

Unspecified

Note

For all the preceding cause values, SMF deactivates the UPF N3 tunnel for the QoS flows with the failed switching for Target RAN. SMF maintains an N2 cause-based statistics under N2 message type.