5.6.1.2.1 UE is not using 5GS services with control plane CIoT 5GS optimization

The UE initiates the service request procedure by sending a SERVICE REQUEST message to the AMF. The UE shall start timer T3517 and enter the state 5GMM-SERVICE-REQUEST-INITIATED.

If the UE is sending the SERVICE REQUEST message from 5GMM-IDLE mode and the UE needs to send non-cleartext IEs, the UE shall send the SERVICE REQUEST message including the NAS message container IE as described in clause 4.4.6.

For cases a, b and g in clause 5.6.1.1, the service type IE in the SERVICE REQUEST message shall be set to "mobile terminated services".

For cases c, d, e, f, i, j, l, la, m, n, and q in clause 5.6.1.1, if the UE is a UE configured for high priority access in selected PLMN or SNPN, the service type IE in the SERVICE REQUEST message shall be set to "high priority access".

For case a in clause 5.6.1.1:

• if the paging request includes an indication for non-3GPP access type, the Allowed PDU session status IE shall be included in the SERVICE REQUEST message. If the UE has PDU session(s) over non-3GPP access, where:
• the associated S-NSSAI(s) are included in the allowed NSSAI for 3GPP access or the partially allowed NSSAI for 3GPP access and the current TAI is in the list of TAs for which the S-NSSAI is allowed; and
• the UE is currently located inside the NS-AoS of the S-NSSAI, if the S-NSSAI location validity information is available,

the UE shall indicate the PDU session(s) for which the UE allows the user-plane resources to be re-established over 3GPP access in the Allowed PDU session status IE; otherwise, the UE shall not indicate any PDU session(s) in the Allowed PDU session status IE; and

• if the UE has uplink user data pending to be sent over 3GPP access, the Uplink data status IE shall be included in the SERVICE REQUEST message to indicate the PDU session(s) for which the UE has pending user data to be sent. Otherwise, the Uplink data status IE shall not be included in the SERVICE REQUEST message.

For case b in clause 5.6.1.1:

• the Allowed PDU session status IE shall be included in the SERVICE REQUEST message. If the UE has PDU session(s) over non-3GPP access where:
• the associated S-NSSAI(s) are included in the allowed NSSAI for 3GPP access or the partially allowed NSSAI for 3GPP access and the current TAI is in the list of TAs for which the S-NSSAI is allowed; and
• the UE is currently located inside the NS-AoS of the S-NSSAI, if the S-NSSAI location validity information is available,

the UE shall indicate the PDU session(s) for which the UE allows the user-plane resources to be re-established over 3GPP access in the Allowed PDU session status IE; otherwise, the UE shall not indicate any PDU session(s) in the Allowed PDU session status IE; and

• if the UE has uplink user data pending to be sent over 3GPP access, the Uplink data status IE shall be included in the SERVICE REQUEST message to indicate the PDU session(s) for which the UE has pending user data to be sent. Otherwise, the Uplink data status IE shall not be included in the SERVICE REQUEST message.

For cases a and b in clause 5.6.1.1, if the UE is in a non-allowed area or the UE is not in an allowed area, the UE shall set the Allowed PDU session status IE as specified in clause 5.3.5.2.

When the Allowed PDU session status IE is included in the SERVICE REQUEST message, the UE shall indicate that a PDU session is not allowed to be transferred to the 3GPP access if the 3GPP PS data off UE status is "activated" for the corresponding PDU session and the UE is not using the PDU session to send uplink IP packets for any of the 3GPP PS data off exempt services (see clause 6.2.10).

For case c in clause 5.6.1.1, the Uplink data status IE shall not be included in the SERVICE REQUEST message except if the UE has one or more active always-on PDU sessions associated with the access type over which the SERVICE REQUEST message is sent. If the UE is not a UE configured for high priority access in selected PLMN or SNPN and:

• if the SERVICE REQUEST message is triggered by a request for emergency services from the upper layer, the UE shall set the service type IE in the SERVICE REQUEST message to "emergency services"; or
• otherwise, the UE shall set the service type IE to "signalling".

When the UE is in a non-allowed area or is not in an allowed area as specified in clause 5.3.5 and:

• if the uplink signalling pending is to indicate a change of 3GPP PS data off UE status for a PDU session, the UE shall set the service type IE in the SERVICE REQUEST message to "elevated signalling", and shall not include the Uplink data status IE in the SERVICE REQUEST message even if the UE has one or more active always-on PDU sessions associated with the access type over which the SERVICE REQUEST message is sent; or
• otherwise, the UE shall not initiate service request procedure except for emergency services, high priority access or responding to paging or notification.

For cases d and e in clause 5.6.1.1, the Uplink data status IE shall be included in the SERVICE REQUEST message to indicate the PDU session(s) the UE has pending user data to be sent. If the UE is not a UE configured for high priority access in selected PLMN or SNPN:

• if there exists an emergency PDU session which is indicated in the Uplink data status IE the service type IE in the SERVICE REQUEST message shall be set to "emergency services"; or
• otherwise, the service type IE in the SERVICE REQUEST message shall be set to "data".

NOTE 1: For a UE in NB-N1 mode, the Uplink data status IE cannot be used to request the establishment of user-plane resources such that there will be user-plane resources established for a number of PDU sessions that exceeds the UE's maximum number of supported user-plane resources.

For case f in clause 5.6.1.1:

• if the UE has uplink user data pending to be sent, the Uplink data status IE shall be included in the SERVICE REQUEST message to indicate the PDU session(s) the UE has pending user data to be sent. If the UE is not a UE configured for high priority access in selected PLMN or SNPN, the service type IE in the SERVICE REQUEST message shall be set to "data";
• otherwise, if the UE is not a UE configured for high priority access in selected PLMN or SNPN, the service type IE in the SERVICE REQUEST message shall be set to "signalling".

For case g in clause 5.6.1.1, if the UE has uplink user data pending to be sent, the Uplink data status IE shall be included in the SERVICE REQUEST message to indicate the PDU session(s) the UE has pending user data to be sent.

For case h in clause 5.6.1.1, the UE shall send a SERVICE REQUEST message with service type set to "emergency services fallback" and without an Uplink data status IE.

For case i in clause 5.6.1.1, if the UE is not configured for high priority access in selected PLMN or SNPN, the UE shall set the Service type IE in the SERVICE REQUEST message as follows:

• if the pending message is an UL NAS TRANSPORT message with the Request type IE set to "initial emergency request" or "existing emergency PDU session", the UE shall set the Service type IE in the SERVICE REQUEST message to "emergency services"; or
• otherwise, the UE shall set the Service type IE in the SERVICE REQUEST message to "signalling".

For case j in clause 5.6.1.1:

• the UE shall include the Uplink data status IE in the SERVICE REQUEST message indicating the PDU session(s) for which the UE has uplink user data pending and the PDU session(s) for which user-plane resources were active prior to receiving the fallback indication or "RRC Connection failure" indication from the lower layers, if any; and
• if the UE is not a UE configured for high priority access in selected PLMN or SNPN, the UE shall set the Service type IE in the SERVICE REQUEST message as follows:
• if there is an emergency PDU session which is indicated in the Uplink data status IE, the UE shall set the Service type IE in the SERVICE REQUEST message to "emergency services"; or
• if there is no emergency PDU session which is indicated in the Uplink data status IE, the UE shall set the Service type IE in the SERVICE REQUEST message to "data".

For cases l, la, n, and q in clause 5.6.1.1, if the UE is not a UE configured for high priority access in selected PLMN or SNPN:

• if there exists an emergency PDU session which is indicated in the Uplink data status IE the service type IE in the SERVICE REQUEST message shall be set to "emergency services"; or
• otherwise, the service type IE in the SERVICE REQUEST message shall be set to "signalling".

For case m in clause 5.6.1.1, the UE shall not include the Paging restriction IE in the SERVICE REQUEST message and set Service type to "signalling". The UE may include the UE request type IE and set Request type to "NAS signalling connection release" to remove the paging restriction and request the release of the NAS signalling connection at the same time. If the UE requests the release of the NAS signalling connection, the UE shall not include the Uplink data status IE in the SERVICE REQUEST message.

For cases o and p in clause 5.6.1.1, the UE shall not include the Uplink data status IE and the Allowed PDU session status IE in the SERVICE REQUEST message. Further,

• for case o in clause 5.6.1.1, the UE shall set Request type to "NAS signalling connection release" in the UE request type IE and Service type to "signalling";
• for case p in clause 5.6.1.1, the UE shall set Request type to "Rejection of paging" in the UE request type IE and Service type to "mobile terminated services"; and

may include its paging restriction preference in the Paging restriction IE in the SERVICE REQUEST message.

The UE shall include a valid 5G-S-TMSI in the 5G-S-TMSI IE of the SERVICE REQUEST message.

For all cases except cases o and p in clause 5.6.1.1, if the UE has one or more active always-on PDU sessions associated with the access type over which the SERVICE REQUEST message is sent and the user-plane resources for these PDU sessions are not established:

• if the S-NSSAI associated with the PDU session is:
• included in the partially allowed NSSAI and the TA where the UE is currently camped is not in list of TAs for which the S-NSSAI is allowed; or
• included in the S-NSSAI location validity information and the UE is outside the NS-AoS of the S-NSSAI;

then the UE shall not indicate those PDU session(s), including always-on PDU session(s), in Uplink data status IE in the SERVICE REQUEST message; or

• otherwise, the UE shall include the Uplink data status IE in the SERVICE REQUEST message and indicate that the UE has pending user data to be sent for those PDU sessions.

If the UE has one or more active PDU sessions which are not accepted by the network as always-on PDU sessions and no uplink user data pending to be sent for those PDU sessions, the UE shall not include those PDU sessions in the Uplink data status IE in the SERVICE REQUEST message.

The Uplink data status IE may be included in the SERVICE REQUEST message to indicate which PDU session(s) associated with the access type the SERVICE REQUEST message is sent over have pending user data to be sent or are associated with active multicast MBS session(s). If the UE is located outside the LADN service area of a PDU session, the UE shall not include the PDU session for LADN in the Uplink data status IE.

If the UE is in a non-allowed area or the UE is not in an allowed area, the UE shall apply the restrictions for the inclusion of the Uplink data status IE specified in clause 5.3.5.2.

The PDU session status information element may be included in the SERVICE REQUEST message to indicate:

• the single access PDU session(s) not in 5GSM state PDU SESSION INACTIVE in the UE associated with the access type the SERVICE REQUEST message is sent over; and
• the MA PDU session(s) not in 5GSM state PDU SESSION INACTIVE and having the corresponding user plane resources being established or established in the UE on the access the SERVICE REQUEST message is sent over.

If the SERVICE REQUEST message includes a NAS message container IE, the AMF shall process the SERVICE REQUEST message that is obtained from the NAS message container IE as described in clause 4.4.6.

If the UE has an emergency PDU session over the non-current access, it shall not initiate the SERVICE REQUEST message with the service type IE set to "emergency services" over the current access, unless the SERVICE REQUEST message has to be initiated to perform handover of an existing emergency PDU session from the non-current access to the current access.

NOTE 2: Transfer of an existing emergency PDU session between 3GPP access and non-3GPP access is needed, e.g. if the UE determines that the current access is no longer available.