Section: 5.5.1.2.5B1 Attach by a UE transferring an emergency PDU session using a standalone PDN CONNECTIVITY REQUEST message
Content: If the network cannot accept attach request including a PDN CONNECTIVITY REQUEST message with request type set to "handover" and the UE also intends to transfer an emergency PDU session, the UE shall attempt EPS attach for emergency bearer services including a PDN CONNECTIVITY REQUEST message with request type set to "handover of emergency bearer services" for the emergency PDU session. If the attach request, including a PDN CONNECTIVITY REQUEST message with request type set "handover", fails due to abnormal case a) in clause 5.5.1.2.6 and the UE intends to transfer an emergency PDU session, the UE shall attempt EPS attach including a PDN CONNECTIVITY REQUEST message with request type set to "handover of emergency bearer services" for the emergency PDU session. If the attach request including a PDN CONNECTIVITY REQUEST message with request type set "handover" fails due to abnormal cases b), c), d) or o) in clause 5.5.1.2.6, the UE intends to transfer an emergency PDU session: - if an EMM cause set to #19 "ESM failure" is received, the UE shall attempt EPS attach; and - otherwise, the UE shall attempt EPS attach for emergency bearer services, with the ATTACH REQUEST message including a PDN CONNECTIVITY REQUEST message with request type set to "handover of emergency bearer services" for the emergency PDU session.