Patent ID: 11006478

Abstract:
A method for Procedure Transaction Identity (PTI) exception handling on protocol data unit (PDU) session modification and establishment procedure is proposed. If a UE receives a PDU SESSION MODIFICATION COMMAND message in which the PTI value is an assigned value that does not match any PTI in use, the UE stays in the current 5GSM state and sends a 5GSM STATUS message including 5GSM cause #47 “PTI mismatch”, and the network will send another COMMAND message with the correct PTI value. If the UE receives a PDU SESSION ESTABLISHMENT ACCEPT or REJECT message in which the PTI value is an assigned value that does not match any PTI in use, the UE responds with a 5GSM STATUS message including 5GSM cause #47 “PTI mismatch”, and the network will send another ACCEPT or REJECT message with the correct PTI value.