Avoiding multiple retransmissions of signalling transported by 5G NAS transport

Abstract

Embodiments herein relate to a wireless device and an Access and Mobility Management Function, AMF, and methods performed by a wireless device and an AMF, respectively.

Claims

1. A method implemented in a wireless device, the method comprising: transmitting an uplink (UL) transport message to an Access and Mobility Function (AMF), wherein the UL transport message comprises: i) a first information element (IE) containing a packet data unit (PDU) session identity (ID) and ii) a second IE containing a 5G session management (5GSM) message to be forwarded by the AMF to a Session Management Function (SMF); and after transmitting the UL transport message to the AMF, receiving a message transmitted by the AMF, wherein the message transmitted by the AMF comprises: i) a container IE containing said 5GSM message that was contained in the UL transport message and ii) a cause IE containing information indicating non-delivery of the 5GSM message.

2. The method of claim 1, wherein the 5GSM message is a PDU SESSION ESTABLISHMENT REQUEST message or a PDU SESSION MODIFICATION REQUEST message.

3. The method of claim 2, wherein the UL transport message further comprises a request type IE containing a type value identifying a 5GSM message type.

4. The method of claim 1, wherein the message transmitted by the AMF further comprises a PDU session ID IE containing the PDU session ID.

5. The method of claim 1, wherein the 5GSM message is a PDU SESSION ESTABLISHMENT REQUEST, and the UL transport message further comprises a request type IE containing a type value set to initial request.

6. The method of claim 5, the method further comprising: as a result of receiving the indication of non-delivery, stopping a timer and determining that a session associated with the 5GSM message is: (i) not established, (ii) not modified, or (iii) not released.

7. The method of claim 1, wherein the indication of non-delivery comprises a cause of failure indication.

8. A wireless device, the wireless device comprising: a receiver; a transmitter; and processing circuitry coupled to the receiver and the transmitter, wherein the wireless device is configured to: transmit an uplink (UL) transport message to a Access and Mobility Function (AMF), wherein the UL transport message comprises: i) a first information element (IE) containing a packet data unit (PDU) session identity (ID) and ii) a second IE containing a 5G session management (5GSM) message to be forwarded by the AMF to a Session Management Function (SMF); and after transmitting the UL transport message, receive a message transmitted by the AMF, wherein the message comprises: i) a container IE containing said 5GSM message that was contained in the UL transport message and ii) a cause IE containing information indicating non-delivery of the 5GSM message.

9. A method performed by a 3GPP Access and Mobility Management Function (AMF), comprising: receiving an uplink (UL) transport message transmitted by a user equipment (UE), wherein the UL transport message comprises: i) a first information element (IE) containing a packet data unit (PDU) session identity (ID) and ii) a second IE containing a 5G session management (5GSM) message to be forwarded by the AMF to a Session Management Function (SMF); determining whether the 5GSM message can be forwarded to a Session Management Function (SMF); as a result of determining that the 5GSM cannot be forwarded to a SMF, transmitting to the UE a message comprising: i) a container IE containing said 5GSM message that was contained in the UL transport message and ii) a cause IE containing information indicating non-delivery of the 5GSM message.

10. The method of claim 9, wherein the message transmitted to the UE further comprises a PDU session ID IE containing the PDU session ID.

11. The method of claim 9, wherein the 5GSM message is a PDU SESSION ESTABLISHMENT REQUEST message or a PDU SESSION MODIFICATION REQUEST message.

12. The method of claim 9, wherein the 5GSM message comprises a procedure transaction identity indication identifying a session management transaction.

13. The method of claim 9, wherein the UL transport message further comprises a request type IE containing a type value identifying a 5GSM message type.

14. The method of claim 13, wherein the determining whether the 5GSM message can be forwarded to a SMF comprises: determining whether the AMF has a PDU session routing context for the PDU session identity, wherein the request type IE indicates that the 5GSM message is associated to an initial request; and as a result of determining that the AMF does not have a PDU session routing context for the PDU session identity, determining that a SMF cannot be selected for the 5GSM message.

15. The method of claim 10, wherein the determining whether the 5GSM message can be forwarded to a SMF comprises: determining whether the AMF has a PDU session routing context for the PDU session identity, wherein the request type IE indicates that the 5GSM message is associated to an existing PDU session; obtaining subscription context for the UE from a unified data management (UDM), wherein the subscription context comprises a SMF identifier (ID); and after determining: (i) that the AMF does not have a PDU session routing context for the PDU session identity and (ii) that the SMF ID is not associated with the DNN, determining that a SMF cannot be selected for the 5GSM message.

16. The method of claim 13, wherein the determining whether the 5GSM message can be forwarded to a SMF comprises: determining whether the AMF has a PDU session routing context for the PDU session identity, wherein the request type IE indicates that the 5GSM message is associated to an existing PDU session, and the DNN is not included in the UL transport message; obtaining subscription context for the UE from a unified data management, UDM, wherein the subscription context comprises a SMF identifier (ID); and after determining: (i) that the AMF does not have a PDU session routing context for the PDU session identity and (ii) that the SMF ID is not associated with a default DNN, determining that a SMF cannot be selected for the 5GSM message.

17. The method of claim 13, wherein the determining whether the 5GSM message can be forwarded to a SMF comprises: determining whether the AMF has a PDU session routing context for the PDU session identity, wherein the request type IE is not included in the UL transport message; and after determining that the AMF does not have a PDU session routing context for the PDU session identity, determining that a SMF cannot be selected for the 5GSM message.

18. The method of claim 9, wherein the 5GSM message is a PDU SESSION ESTABLISHMENT REQUEST, and the UL transport message further comprises a request type IE containing a type value set to initial request.

19. The method of claim 9, further comprising: obtaining user data; and forwarding the user data to a host computer or a wireless device.

20. A 3GPP Access and Mobility Management Function (AMF) entity configured to perform the method of claim 9.

21. The AMF entity of claim 20, wherein the determining whether 5GSM message can be forwarded to a SMF is at least partly based on the UL transport message.

Description

EMBODIMENTS

Group A Embodiments—UE

(1) A1. A method implemented in a wireless device, comprising:

(2) transmitting a transport message (e.g., UL SM Message Transport message) to an Access and Mobility Function (AMF), wherein the transport message comprises a SM message (e.g., 5GSM message); and

(3) receiving a status message (e.g., 5GMM Status message) transmitted by the AMF, wherein the status message comprises at least a portion of the transport message and an indication of non-delivery of the SM message to a SMF.

(4) A2. The method of A1, wherein the portion of the transport message comprises the SM message.

(5) A3. The method of A1 or A2, wherein the transport message further comprises at least one or more of: a protocol data unit (PDU) session identifier (ID), a data network name (DNN), and a request type indication.

(6) A4. The method of any one of A1-A3, wherein the SM message comprises a procedure transaction identity (PTI) indication identifying a session management transaction (e.g., 5GSM transaction) associated with the SM message.

(7) A5. The method of any one of A1-A4, wherein the SM message is one of: (i) a session establishment request message (e.g., PDU Session Establishment Request message), (ii) a session modification request message (e.g., PDU Session Modification Request message), and (iii) a session release request message (e.g., PDU Session Release Request message), the method further comprising:

(8) as a result of receiving the indication of non-delivery, stopping a timer (e.g., Tx, Tk or Tz).

(9) A6. The method of A5, the method further comprising:

(10) as a result of receiving the indication of non-delivery, determining that a session associated with the SM message is: (i) not established, (ii) not modified or (iii) not released.

(11) A7. The method of any one of A1-A6, wherein the indication of non-delivery comprises a cause of failure to deliver the SM message to a SMF.

(12) A8. The method of any of the previous embodiments, further comprising:

(13) providing user data; and

(14) forwarding the user data to a host computer via the transmission to the base station.

Group B Embodiments—Base Station

(15) B1. A method performed by an Access and Mobility Management Function (AMF), comprising:

(16) receiving a transport message (e.g., UL SM Message Transport message) transmitted by a wireless device, wherein the transport message comprises a SM message (e.g., 5GSM message);

(17) determining, based on the transport message, whether the SM message can be forwarded to a SMF;

(18) as a result of determining that the SM message cannot be forwarded to a SMF, creating a status message (e.g., 5GMM Status message) comprising at least a portion of the transport message and an indication of non-delivery of the SM message to a SMF; and

(19) transmitting the status message to the wireless device.

(20) B2. The method of B1, wherein the portion of the transport message comprises the SM message.

(21) B3. The method of B1 or B2, wherein the SM message comprises a procedure transaction identity (PTI) indication identifying a session management transaction (e.g., 5GSM transaction) associated with the SM message.

(22) B4. The method of any one of B1-B3, wherein the transport message further comprises at least one or more of: a protocol data unit (PDU) session identifier (ID), a data network name (DNN), and a request type indication.

(23) B5. The method of B4, wherein the determining, based on the transport message, whether the SM message can be forwarded to a SMF further comprises:

(24) determining whether the AMF has a PDU session routing context for the PDU session identifier, wherein the request type indication indicates that the SM message is associated to an initial request; and

(25) as a result of determining that the AMF does not have a PDU session routing context for the PDU session identifier, determining that a SMF cannot be selected for the SM message.

(26) B6. The method of B4, wherein the determining, based on the transport message, whether the SM message can be forwarded to a SMF further comprises:

(27) determining whether the AMF has a PDU session routing context for the PDU session identifier, wherein the request type indication indicates that the SM message is associated to an existing PDU session;

(28) obtaining subscription context for the wireless device from a unified data management (UDM), wherein the subscription context comprises at least one or more SMF identifier (ID); and

(29) as a result of determining: (i) that the AMF does not have a PDU session routing context for the PDU session identifier and (ii) the at least one or more SMF ID is not associated with the DNN, determining that a SMF cannot be selected for the SM message.

(30) B7. The method of B4, wherein the determining, based on the transport message, whether the SM message can be forwarded to a SMF further comprises:

(31) determining whether the AMF has a PDU session routing context for the PDU session identifier, wherein the request type indication indicates that the SM message is associated to an existing PDU session, and the DNN is not included in the transport message;

(32) obtaining subscription context for the wireless device from a unified data management (UDM), wherein the subscription context comprises at least one or more SMF identifier (ID); and

(33) as a result of determining: (i) that the AMF does not have a PDU session routing context for the PDU session identifier and (ii) the at least one or more SMF ID is not associated with a default DNN, determining that a SMF cannot be selected for the SM message.

(34) B8. The method of B4, wherein the determining, based on the transport message, whether the SM message can be forwarded to a SMF further comprises:

(35) determining whether the AMF has a PDU session routing context for the PDU session identifier, wherein the request type indication is not included in the transport message; and

(36) as a result of determining that the AMF does not have a PDU session routing context for the PDU session identifier, determining that a SMF cannot be selected for the SM message.

(37) B9. The method of any one of B1-B8, wherein the indication of non-delivery comprises a cause of failure to deliver the SM message to a SMF.

(38) B10. The method of any of the previous embodiments, further comprising:

(39) obtaining user data; and

(40) forwarding the user data to a host computer or a wireless device.

Group C Embodiments

(41) C1. A wireless device comprising:

(42) processing circuitry configured to perform any of the steps of any of the Group A embodiments; and

(43) power supply circuitry configured to supply power to the wireless device.

(44) C2. A base station, the base station comprising:

(45) processing circuitry configured to perform any of the steps of any of the Group B embodiments;

(46) power supply circuitry configured to supply power to the wireless device.

(47) C3. A user equipment (UE) comprising:

(48) an antenna configured to send and receive wireless signals;

(49) radio front-end circuitry connected to the antenna and to processing circuitry, and configured to condition signals communicated between the antenna and the processing circuitry;

(50) the processing circuitry being configured to perform any of the steps of any of the Group A embodiments;

(51) an input interface connected to the processing circuitry and configured to allow input of information into the UE to be processed by the processing circuitry;

(52) an output interface connected to the processing circuitry and configured to output information from the UE that has been processed by the processing circuitry; and

(53) a battery connected to the processing circuitry and configured to supply power to the UE.

(54) C4. A communication system including a host computer comprising:

(55) processing circuitry configured to provide user data; and

(56) a communication interface configured to forward the user data to a cellular network for transmission to a user equipment (UE),

(57) wherein the cellular network comprises a base station having a radio interface and processing circuitry, the base station's processing circuitry configured to perform any of the steps of any of the Group B embodiments.

(58) C5. The communication system of the pervious embodiment further including the base station.

(59) C6. The communication system of the previous 2 embodiments, further including the UE, wherein the UE is configured to communicate with the base station.

(60) C7. The communication system of the previous 3 embodiments, wherein:

(61) the processing circuitry of the host computer is configured to execute a host application, thereby providing the user data; and

(62) the UE comprises processing circuitry configured to execute a client application associated with the host application.

(63) C8. A method implemented in a communication system including a host computer, a base station and a user equipment (UE), the method comprising:

(64) at the host computer, providing user data; and

(65) at the host computer, initiating a transmission carrying the user data to the UE via a cellular network comprising the base station, wherein the base station performs any of the steps of any of the Group B embodiments.

(66) C9. The method of the previous embodiment, further comprising, at the base station, transmitting the user data.

(67) C10. The method of the previous 2 embodiments, wherein the user data is provided at the host computer by executing a host application, the method further comprising, at the UE, executing a client application associated with the host application.

(68) C11. A user equipment (UE) configured to communicate with a base station, the UE comprising a radio interface and processing circuitry configured to performs the of the previous 3 embodiments.

(69) C12. A communication system including a host computer comprising:

(70) processing circuitry configured to provide user data; and

(71) a communication interface configured to forward user data to a cellular network for transmission to a user equipment (UE),

(72) wherein the UE comprises a radio interface and processing circuitry, the UE's components configured to perform any of the steps of any of the Group A embodiments.

(73) C13. The communication system of the previous embodiment, wherein the cellular network further includes a base station configured to communicate with the UE.

(74) C14. The communication system of the previous 2 embodiments, wherein:

(75) the processing circuitry of the host computer is configured to execute a host application, thereby providing the user data; and

(76) the UE's processing circuitry is configured to execute a client application associated with the host application.

(77) C15. A method implemented in a communication system including a host computer, a base station and a user equipment (UE), the method comprising:

(78) at the host computer, providing user data; and

(79) at the host computer, initiating a transmission carrying the user data to the UE via a cellular network comprising the base station, wherein the UE performs any of the steps of any of the Group A embodiments.

(80) C16. The method of the previous embodiment, further comprising at the UE, receiving the user data from the base station.

(81) C17. A communication system including a host computer comprising:

(82) communication interface configured to receive user data originating from a transmission from a user equipment (UE) to a base station,

(83) wherein the UE comprises a radio interface and processing circuitry, the UE's processing circuitry configured to perform any of the steps of any of the Group A embodiments.

(84) C18. The communication system of the previous embodiment, further including the UE.

(85) C19. The communication system of the previous 2 embodiments, further including the base station, wherein the base station comprises a radio interface configured to communicate with the UE and a communication interface configured to forward to the host computer the user data carried by a transmission from the UE to the base station.

(86) C20. The communication system of the previous 3 embodiments, wherein:

(87) the processing circuitry of the host computer is configured to execute a host application; and

(88) the UE's processing circuitry is configured to execute a client application associated with the host application, thereby providing the user data.

(89) C21. The communication system of the previous 4 embodiments, wherein:

(90) the processing circuitry of the host computer is configured to execute a host application, thereby providing request data; and

(91) the UE's processing circuitry is configured to execute a client application associated with the host application, thereby providing the user data in response to the request data.

(92) C22. A method implemented in a communication system including a host computer, a base station and a user equipment (UE), the method comprising:

(93) at the host computer, receiving user data transmitted to the base station from the UE, wherein the UE performs any of the steps of any of the Group A embodiments.

(94) C23. The method of the previous embodiment, further comprising, at the UE, providing the user data to the base station.

(95) C24. The method of the previous 2 embodiments, further comprising:

(96) at the UE, executing a client application, thereby providing the user data to be transmitted; and

(97) at the host computer, executing a host application associated with the client application.

(98) C25. The method of the previous 3 embodiments, further comprising:

(99) at the UE, executing a client application; and

(100) at the UE, receiving input data to the client application, the input data being provided at the host computer by executing a host application associated with the client application,

(101) wherein the user data to be transmitted is provided by the client application in response to the input data.

(102) C26. A communication system including a host computer comprising a communication interface configured to receive user data originating from a transmission from a user equipment (UE) to a base station, wherein the base station comprises a radio interface and processing circuitry, the base station's processing circuitry configured to perform any of the steps of any of the Group B embodiments.

(103) C27. The communication system of the previous embodiment further including the base station.

(104) C28. The communication system of the previous 2 embodiments, further including the UE, wherein the UE is configured to communicate with the base station.

(105) C29. The communication system of the previous 3 embodiments, wherein:

(106) the processing circuitry of the host computer is configured to execute a host application;

(107) the UE is configured to execute a client application associated with the host application, thereby providing the user data to be received by the host computer.

(108) C30. A method implemented in a communication system including a host computer, a base station and a user equipment (UE), the method comprising:

(109) at the host computer, receiving, from the base station, user data originating from a transmission which the base station has received from the UE, wherein the UE performs any of the steps of any of the Group A embodiments.

(110) C31. The method of the previous embodiment, further comprising at the base station, receiving the user data from the UE.

(111) C32. The method of the previous 2 embodiments, further comprising at the base station, initiating a transmission of the received user data to the host computer.

(112) While various embodiments of the present disclosure are described herein (including the attached appendix), it should be understood that they have been presented by way of example only, and not limitation. Thus, the breadth and scope of the present disclosure should not be limited by any of the above described exemplary embodiments. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the disclosure unless otherwise indicated herein or otherwise clearly contradicted by context.

(113) Additionally, while the processes described above and illustrated in the drawings are shown as a sequence of steps, this was done solely for the sake of illustration. Accordingly, it is contemplated that some steps may be added, some steps may be omitted, the order of the steps may be re-arranged, and some steps may be performed in parallel.

APPENDIX

(114) 2. Reason for Change

(115) 2.1 Problem Description

(116) TR 24.890 contains the following editor's notes:

(117) 8.5.1.1.2.1.1.4 Abnormal cases on the network side

(118) --------------

(119) The following abnormal cases in AMF are identified:

(120) a) the AMF does not have a PDU session routing context for the PDU session ID of the UL SM MESSAGE TRANSPORT message and the UE, the request type IE of the UL SM MESSAGE TRANSPORT message is set to “initial request”, and the SMF selection fails. Editor's note: Handling of this abnormal case is FFS
. . . b) the AMF does not have a PDU session routing context for the PDU session ID of the UL SM MESSAGE TRANSPORT message and the UE, the request type IE of the UL SM MESSAGE TRANSPORT message is set to “existing PDU session”, and the user's subscription context obtained from the UDM does not contain an SMF ID corresponding to. 1) the DNN of the UL SM MESSAGE TRANSPORT message, if the DNN is included in the NAS SM MESSAGE TRANSPORT message; or 2) the default DNN, if the DNN is not included in the UL SM MESSAGE TRANSPORT message. Editor's note: Handling of this abnormal case is FFS
--------------
Similar error can also occur when request type is not provided by the UE.
If no handling is defined for the cases above, the failure is due to a permanent cause (e.g. the requested DNN is not authorized DNN for the UE) and the SM messages are retransmitted, then the UE will retransmit the SM message in a new UL SM MESSAGE TRANSPORT message and the AMF needs to repeat the SMF selection again with the same failure.
2.2 Possible Solutions
2.2.1 Alternative-1
UE-initiated NAS transport procedure is extended with an UL SM MESSAGE TRANSPORT ACCEPT message or an UL SM MESSAGE TRANSPORT REJECT message, which AMF sends upon reception and handling of UL SM MESSAGE TRANSPORT REQUEST message. Only up to one UE-initiated NAS transport procedure would be run at any given time.
If the AMF is able to forward 5GSM message of UL SM MESSAGE TRANSPORT REQUEST message, the AMF sends UL SM MESSAGE TRANSPORT ACCEPT message.
If the AMF is unable to forward 5GSM message of UL SM MESSAGE TRANSPORT REQUEST message, the AMF sends UL SM MESSAGE TRANSPORT REJECT message. The UL SM MESSAGE TRANSPORT REJECT message contains a cause.
As reliability is provided on SM transport layer, the 5GSM procedures will not need to retransmit 5GSM messages.
If transport of 5GSM message fails, the 5GSM procedure will consider the 5GSM procedure as unsuccessfully completed.
2.2.2 Alternative-2
If the AMF is unable to forward 5GSM message of UL SM MESSAGE TRANSPORT message, the AMF sends 5GMM STATUS message. The 5GMM STATUS message contains a 5GMM message container IE containing the UL SM MESSAGE TRANSPORT message, and a cause.
If the UE receives a 5GMM STATUS message with 5GMM message container IE containing the UL SM MESSAGE TRANSPORT message containing a 5GSM message, the 5GMM layer informs the 5GSM layer about non-delivery of the 5GSM message.
Based on non-delivery of the 5GSM message, the 5GSM procedure will stop any retransmissions of the 5GSM message and consider the 5GSM procedure as unsuccessfully completed.
2.2.3 Alternative-3
AMF is configured with a SMF for rejection.
AMF routes any SM message which is unable to route forward to the SMF for rejection. The SMF rejects the 5GSM request message with appropriate 5GSM response message.
2.2.4 Alternative-4
Do nothing and live with retransmissions in case of AMF not being able to select an SMF.
2.3 Evaluation
Alternative-1 requires two NAS messages to transport a 5G SM message while the existing procedure requires only 1 NAS message.
Alternative-3 requires deployment of an SMF. The SMF does not need to be fully functional—it only needs to be able to reject the 5GSM message from the UE.
Alternative-4 does not solve the problem.
4. Proposal
It is proposed to apply alternative-2.
It is proposed to agree the following changes to 3GPP TR 24.890.
8.5.1.1.2.1.1.4 Abnormal cases on the network side
The following abnormal cases in AMF are identified: a) if the AMF does not have a PDU session routing context for the PDU session ID of the UL SM MESSAGE TRANSPORT message and the UE, the request type IE of the UL SM MESSAGE TRANSPORT message is set to “initial request”, and the SMF selection fails, then the AMF shall create a 5GMM STATUS message. The AMF shall set the 5GMM message container IE of the 5GMM STATUS message to the UL SM MESSAGE TRANSPORT message. The AMF shall set the cause IE of the 5GMM STATUS message to a cause indicating cause of failure. The AMF shall send the 5GMM STATUS message to the UE. b) if the AMF does not have a PDU session routing context for the PDU session ID of the UL SM MESSAGE TRANSPORT message and the UE, the request type IE of the UL SM MESSAGE TRANSPORT message is set to “existing PDU session”, and the user's subscription context obtained from the UDM does not contain an SMF ID corresponding to: 1) the DNN of the UL SM MESSAGE TRANSPORT message, if the DNN is included in the NAS SM MESSAGE TRANSPORT message; or 2) the default DNN, if the DNN is not included in the UL SM MESSAGE TRANSPORT message. then the AMF shall create a 5GMM STATUS message. The AMF shall set the 5GMM message container IE of the 5GMM STATUS message to the UL SM MESSAGE TRANSPORT message. The AMF shall set the cause IE of the 5GMM STATUS message to a cause indicating cause of failure. The AMF shall send the 5GMM STATUS message to the UE. c) if the AMF does not have a PDU session routing context for the PDU session ID of the UL SM MESSAGE TRANSPORT message and the UE, and the request type IE of the UL SM MESSAGE TRANSPORT message is not provided, then the AMF shall create a 5GMM STATUS message. The AMF shall set the 5GMM message container IE of the 5GMM STATUS message to the UL SM MESSAGE TRANSPORT message. The AMF shall set the cause IE of the 5GMM STATUS message to a cause indicating cause of failure. The AMF shall send the 5GMM STATUS message to the UE. d) if the AMF has a PDU session routing context for the PDU session ID of the UL SM MESSAGE TRANSPORT message and the UE, the request type IE of the UL SM MESSAGE TRANSPORT message is set to “initial request” and the AMF has not received a reallocation requested indication, the AMF should forward the SM message, the PDU session ID, the S-NSSAI (if received), the DNN (if received) and the request type of the UL SM MESSAGE TRANSPORT message towards the SMF ID of the PDU session routing context. e) if the AMF has a PDU session routing context for the PDU session ID of the UL SM MESSAGE TRANSPORT message and the UE, the PDU session routing context indicates that the PDU session is an emergency PDU session, the request type IE of the UL SM MESSAGE TRANSPORT message is set to “initial emergency request”, the AMF should forward the SM message, the PDU session ID, the S-NSSAI (if received), the DNN (if received) and the request type of the UL SM MESSAGE TRANSPORT message towards the SMF ID of the PDU session routing context. f) if the AMF has a PDU session routing context for the PDU session ID of the UL SM MESSAGE TRANSPORT message and the UE, the request type IE of the UL SM MESSAGE TRANSPORT message is set to “initial request”, the AMF has received a reallocation requested indication from the SMF indicating that the SMF is to be reallocated, and the PDU session routing context contains reallocated SMF ID, the AMF should forward the SM message, the PDU session ID, the S-NSSAI (if received), the DNN (if received) and the request type of the UL SM MESSAGE TRANSPORT message towards the reallocated SMF ID of the PDU session routing context.
8.5.1.1.2.1.1.5 UE-initiated SM message transport initiation not accepted by the network
Upon reception of 5GMM STATUS message with the 5GMM message container IE containing an UL SM MESSAGE TRANSPORT message, the UE passes a non-delivery indication along with the SM message of the UL SM MESSAGE TRANSPORT message to the 5GSM procedures specified in clause 9.
9.4.2.5 Abnormal cases in the UE
The following abnormal cases can be identified: a) Tx expired Editor's note: Further abnormal cases in the UE are FFS. b) Upon receiving a non-delivery indication along with a PDU SESSION ESTABLISHMENT REQUEST message with PTI IE set to the allocated PTI value, the UE shall stop timer Tx, shall release the allocated PTI value and shall consider that the PDU session is not established.
9.4.4.5 Abnormal cases in the UE
The following abnormal cases can be identified: a) Tk expired Editor's note: Further abnormal cases are FFS. b) Upon receiving a non-delivery indication along with a PDU SESSION MODIFICATION REQUEST message with PTI IE set to the allocated PTI value, the UE shall stop timer Tk, shall release the allocated PTI value and shall consider that the PDU session is not modified.
9.4.6.5 Abnormal cases in the UE
The following abnormal cases can be identified: a) Tz expired Editors' note: Further abnormal cases are FFS. b) Upon receiving a non-delivery indication along with a PDU SESSION RELEASE REQUEST message with PTI IE set to the allocated PTI value, the UE shall stop timer Tz, shall release the allocated PTI value and shall consider that the PDU session is not released.

Abbreviations

(121) At least some of the following abbreviations may be used in this disclosure. If there is an inconsistency between abbreviations, preference should be given to how it is used above. If listed multiple times below, the first listing should be preferred over any subsequent listing(s). 1×RTT CDMA2000 1× Radio Transmission Technology 3GPP 3rd Generation Partnership Project 5G 5th Generation ABS Almost Blank Subframe ARQ Automatic Repeat Request AWGN Additive White Gaussian Noise BCCH Broadcast Control Channel BCH Broadcast Channel CA Carrier Aggregation CC Carrier Component CCCH SDU Common Control Channel SDU CDMA Code Division Multiplexing Access CGI Cell Global Identifier CIR Channel Impulse Response CP Cyclic Prefix CPICH Common Pilot Channel CPICH Ec/No CPICH Received energy per chip divided by the power density in the band CQI Channel Quality information C-RNTI Cell RNTI CSI Channel State Information DCCH Dedicated Control Channel DL Downlink DM Demodulation DMRS Demodulation Reference Signal DRX Discontinuous Reception DTX Discontinuous Transmission DTCH Dedicated Traffic Channel DUT Device Under Test E-CID Enhanced Cell-ID (positioning method) E-SMLC Evolved-Serving Mobile Location Centre ECGIEvolved CGI eNB E-UTRAN NodeB ePDCCH enhanced Physical Downlink Control Channel E-SMLC evolved Serving Mobile Location Center E-UTRA Evolved UTRA E-UTRAN Evolved UTRAN FDD Frequency Division Duplex FFS For Further Study GERAN GSM EDGE Radio Access Network gNB Base station in NR GNSS Global Navigation Satellite System GSM Global System for Mobile communication HARQ Hybrid Automatic Repeat Request HO Handover HSPA High Speed Packet Access HRPD High Rate Packet Data LOS Line of Sight LPP LTE Positioning Protocol LTE Long-Term Evolution MAC Medium Access Control MBMS Multimedia Broadcast Multicast Services MBSFN Multimedia Broadcast multicast service Single Frequency Network MBSFN ABS MBSFN Almost Blank Subframe MDT Minimization of Drive Tests MIB Master Information Block MME Mobility Management Entity MSC Mobile Switching Center NPDCCH Narrowband Physical Downlink Control Channel NR New Radio OCNG OFDMA Channel Noise Generator OFDM Orthogonal Frequency Division Multiplexing OFDMA Orthogonal Frequency Division Multiple Access OSS Operations Support System OTDOA Observed Time Difference of Arrival O&M Operation and Maintenance PBCH Physical Broadcast Channel P-CCPCH Primary Common Control Physical Channel PCell Primary Cell PCFICH Physical Control Format Indicator Channel PDCCH Physical Downlink Control Channel PDP Profile Delay Profile PDSCH Physical Downlink Shared Channel PGW Packet Gateway PHICH Physical Hybrid-ARQ Indicator Channel PLMN Public Land Mobile Network PMI Precoder Matrix Indicator PRACH Physical Random Access Channel PRS Positioning Reference Signal PSS Primary Synchronization Signal PUCCH Physical Uplink Control Channel PUSCH Physical Uplink Shared Channel RACH Random Access Channel QAM Quadrature Amplitude Modulation RAN Radio Access Network RAT Radio Access Technology RLM Radio Link Management RNC Radio Network Controller RNTI Radio Network Temporary Identifier RRC Radio Resource Control RRM Radio Resource Management RS Reference Signal RSCP Received Signal Code Power RSRP Reference Symbol Received Power OR Reference Signal Received Power RSRQ Reference Signal Received Quality OR Reference Symbol Received Quality RSSI Received Signal Strength Indicator RSTD Reference Signal Time Difference SCH Synchronization Channel SCell Secondary Cell SDU Service Data Unit SFN System Frame Number SGW Serving Gateway SI System Information SIB System Information Block SNR Signal to Noise Ratio SON Self Optimized Network SS Synchronization Signal SSS Secondary Synchronization Signal TDD Time Division Duplex TDOA Time Difference of Arrival TOA Time of Arrival TSS Tertiary Synchronization Signal TTI Transmission Time Interval UE User Equipment UL Uplink UMTS Universal Mobile Telecommunication System USIM Universal Subscriber Identity Module UTDOA Uplink Time Difference of Arrival UTRA Universal Terrestrial Radio Access UTRAN Universal Terrestrial Radio Access Network WCDMA Wide CDMA WLAN Wide Local Area Network