This clause defines the structure of the messages of the Layer 3 (L3) protocols defined in the present document. These are standard L3 messages as defined in TS 24.007.
Each definition given in the present clause includes:
a brief description of the message direction and use, including whether the message has:
Local significance, i.e. relevant only on the originating or terminating access;
Access significance, i.e. relevant in the originating and terminating access, but not in the network;
Dual significance, i.e. relevant in either the originating or terminating access and in the network; or
Global significance, i.e. relevant in the originating and terminating access and in the network.
a table listing the Information Elements (IE) known in the message and the order of their appearance in the message. All IEs that may be repeated are explicitly indicated (The V, LV and LV-E formatted IEs, which compose the imperative part of the message, occur before the T, TV, TLV and TLV-E formatted IEs which compose the non-imperative part of the message, see TS 24.007). In a (maximal) sequence of consecutive IEs with half octet length, the first IE with half octet length occupies bits 1 to 4 of octet N, the second IE bits 5 to 8 of octet N, the third IE bits 1 to 4 of octet N+1 etc. Such a sequence always has an even number of elements.
For each information element the table indicates:
The Information Element Identifier (IEI), in hexadecimal notation, if the IE has format T, TV, TLV or TLV-E. If the IEI has half octet length, it is specified by a notation representing the IEI as a hexadecimal digit followed by a "-" (example: B-).
The name of the information element (which may give an idea of the semantics of the element). The name of the information element followed by "IE" or "information element" is used in this technical report as reference to the information element within a message.
The name of the type of the information element (which indicates the coding of the value part of the IE), and generally, the referenced subclause of clause 9 of the present document describing the value part of the information element.
The presence requirement indication (M, C, or O) for the IE as defined in TS 24.007.
The format of the information element (T, V, TV, LV, TLV, LV-E or TLV-E) as defined in TS 24.007.
The length of the information element (or permissible range of lengths), in octets, in the message, where "?" means that the maximum length of the IE is only constrained by link layer protocol. This indication is non-normative.
subclauses specifying, where appropriate, conditions for IEs with presence requirement C or O in the relevant message which together with other conditions specified in the present document define when the information elements shall be included or not, what non-presence of such IEs means, and - for IEs with presence requirement C - the static conditions for presence or non-presence of the IEs or for both cases (see TS 24.007).
This IE shall be included when the AUTHENTICATION RESULT message is provided to a 5G-RG that is acting on behalf of an AUN3 device if the EAP message IE is set to an EAP-success message.
This IE shall be included in a 5G AKA based primary authentication and key agreement procedure if and only if the 5GMM cause was #21 "synch failure". It shall include the response to the authentication challenge from the USIM, which is made up of the AUTS parameter (see TS 33.501).
The AUTHENTICATION REJECT message is sent by the AMF to the UE to indicate that the authentication procedure has failed and that the UE shall abort all activities. See Table 8.2.5.1.1.
The UE shall include this IE if the UE has a valid non-current native 5G NAS security context when the UE performs an inter-system change from S1 mode to N1 mode in 5GMM-CONNECTED mode and the UE uses a mapped 5G NAS security context to protect the REGISTRATION REQUEST message.
This IE shall be included if the UE has uplink user data pending to be sent or the UE has active multicast MBS session(s), unless the UE performs a periodic registration updating procedure.
This IE shall be included when the UE needs to indicate the PDU sessions that are associated with the access type that the message is sent over, that are active within the UE.
This IE shall be included if the UE in single-registration mode performs the registration procedure due to inter-system change from S1 mode to N1 mode or if the UE in dual-registration mode and EMM state EMM-REGISTERED performs initial registration.
if the UE performs the registration procedure due to inter-system change from S1 mode to N1 mode, the UE operates in single-registration mode and the UE has a valid 5G-GUTI; or
the UE holds two valid native 5G-GUTIs and one of the valid native 5G-GUTI was assigned by the PLMN with which the UE is performing the registration.
If the UE wants to use or change the UE specific DRX parameters, the UE shall include the Requested DRX parameters IE in the REGISTRATION REQUEST message.
The UE operating in the single-registration mode shall include this information element as specified in subclause 5.5.1.3.2 if the UE performs mobility from S1 mode to N1 mode in 5GMM-IDLE mode. The content of this message container is the complete integrity protected TRACKING AREA UPATE REQUEST message, using EPS security context.
The UE performing initial registration shall include this information element if
the UE:
was previously registered in S1 mode before entering state EMM-DEREGISTERED; and
has received an "interworking without N26 interface not supported" indication from the network; and
EPS security context and a valid 4G-GUTI are available.
The content of this message container is the complete integrity protected ATTACH REQUEST message, using EPS security context.
The UE shall include this information element when the UE needs to request LADN information for specific LADN DNN(s) or to indicate a request for LADN information.
the UE has one or more stored UE policy sections identified by a UPSI with the PLMN ID part indicating the HPLMN or the selected PLMN for the registration procedure for mobility and periodic registration update due to inter-system change from S1 mode to N1 mode of a UE operating in the single-registration mode or for the registration procedure for initial registration; or
the UE does not have any stored UE policy section identified by a UPSI with the PLMN ID part indicating the HPLMN or the selected PLMN for the registration procedure for mobility and periodic registration update due to inter-system change from S1 mode to N1 mode of a UE operating in the single-registration mode or for the registration procedure for initial registration and the UE needs to send a UE policy container to the network.
Within an SNPN, this IE shall be included if:
the UE has one or more stored UE policy sections for the selected SNPN for the registration procedure for initial registration; or
the UE does not have any UE policy section for the selected SNPN for the registration procedure for initial registration and the UE needs to send a UE policy container to the network.
This IE shall be included when a requested NSSAI is included in the REGISTRATION REQUEST message and the requested NSSAI is created from the default configured NSSAI.
This IE shall be included if the UE is sending a REGISTRATION REQUEST message as an initial NAS message, the UE has a valid 5G NAS security context and the UE needs to send non-cleartext IEs.
The UE shall include this IE if the UE operating in the single-registration mode performs inter-system change from S1 mode to N1 mode and the UE has locally deactivated EPS bearer context(s) for which interworking to 5GS is supported while the UE was in S1 mode without notifying the network.
This IE shall be included by the UE when the UE has a PDN connection or a PDU session to transfer to visited PLMN associated only with an S-NSSAI that is applicable in the HPLMN as specified in subclause 5.5.1.3.2.
The UE shall include this IE if the UE supports ciphered broadcast assistance data and the UE needs to obtain new ciphering keys for ciphered broadcast assistance data.
The UE shall include this IE if the Request type is set to "NAS signalling connection release" in the UE request type IE and the UE requests the network to restrict paging.
The UE shall include this IE if the 5G-GUTI in the 5GS mobile identity IE was assigned by an SNPN other than the SNPN with which the UE is registering.
The UE may include this IE if the UE supports NR paging subgrouping, the UE is not performing initial registration for emergency services, is not registered for emergency services and does not have an active emergency PDU session.
The UE may include this IE during the registration procedure if it requests to use MICO mode and T3324 IE is included, to request a particular T3512 timer value.
The UE may include this IE during the registration procedure for mobility registration update if it requests from the network to keep using the user plane resources of the old non-3GPP access during path switching to the new non-3GPP access.
one or more S-NSSAIs in the requested NSSAI of the REGISTRATION REQUEST message are allowed by the AMF for a network not supporting NSSAA;
one or more S-NSSAIs in the requested NSSAI of the REGISTRATION REQUEST message are not subject to network slice-specific authentication and authorization and are allowed by the AMF; or
the network slice-specific authentication and authorization has been successfully performed for one or more S-NSSAIs in the requested NSSAI of the REGISTRATION REQUEST message; or
if the initial registration request is not for onboarding services in SNPN or the UE is not registered for onboarding services in SNPN, the requested NSSAI was not included in the REGISTRATION REQUEST message or none of the requested NSSAI are allowed; and
the network does not support NSSAA; or
the network has one or more default S-NSSAIs which are not subject to network slice-specific authentication and authorization.
The network may include this IE to inform the UE of one or more S-NSSAIs that were included in the requested NSSAI in the REGISTRATION REQUEST message but were rejected by the network.
The network may include this IE if the network needs to provide the UE with a new configured NSSAI for the current PLMN or SNPN and the UE is neither registering nor registered for onboarding services in SNPN.
The network may include this IE to inform the UE of the support of certain features. If this IE is not included then the UE shall interpret this as a receipt of an information element with all bits of the value part coded as zero.
This IE shall be included when the network needs to indicate the PDU sessions that are associated with the access type the message is sent over, that are active in the network.
if the Uplink data status IE is included in the REGISTRATION REQUEST message; or
if the Allowed PDU session status IE is included in the REGISTRATION REQUEST message and there is at least one PDU session indicated in the Allowed PDU session status IE for which the user-plane resources can be re-established over 3GPP access.
This IE may be included, if the PDU session reactivation result IE is included and there exist one or more PDU sessions for which the user-plane resources cannot be re-established, to indicate the cause of failure to re-establish the user-plane resources.
The AMF shall include this IE during a registration procedure over 3GPP access when the 5GS registration type IE does not indicate "periodic registration updating". The AMF may include this IE during the mobility and periodic registration update procedure over 3GPP access when the 5GS registration type IE indicates "periodic registration updating".
This IE may be included if the network needs to indicate to the UE registered over non-3GPP access the value of a non-3GPP de-registration timer value.
This IE may be sent by the network. If this IE is sent, the contents of this IE indicates a list of emergency numbers valid within the same country as in the PLMN from which this IE is received.
This IE may be sent by the network. If this IE is sent, the contents of this IE indicates a list of emergency numbers (with URN information) valid within the same country as in the PLMN from which this IE is received or valid only in the PLMN or SNPN from which this IE is received.
EAP message IE is included if the REGISTRATION ACCEPT message is sent as part of registration for emergency services and is used to convey EAP-failure message.
This IE may be included to assign new operator-defined access category definitions to the UE or delete the operator-defined access category definitions at the UE side.
The AMF shall not include this IE during a registration procedure over non-3GPP access.
This IE is included if the network needs to indicate whether emergency numbers provided via non-3GPP access can be used to initiate UE detected emergency calls (see TS 24.302). If this IE is not included then the UE shall interpret this as a receipt of an information element with all bits of the value part coded as zero.
The network may include this IE if the congestion control for transport of user data via the control plane is active and the UE supports the control plane CIoT 5GS optimizations.
The AMF shall include this IE if the UE has requested active time value in the REGISTRATION REQEUST message and the AMF decides to accept the use of MICO mode and the use of the active time.
This IE shall be included when the network generated an EPS bearer context status information for the UE during the inter-system change from S1 mode to N1 mode and the network supports N26 interface.
This IE may be included if the UE is not in NB-N1 mode, both the UE and the network support RACS and the network needs to assign a network-assigned UE radio capability ID to the UE.
This IE may be included if the UE is not in NB-N1 mode, both the UE and the network support RACS and the network needs to trigger the UE to delete all network-assigned UE radio capability IDs stored at the UE for the serving PLMN or SNPN.
The network may include this IE to inform the UE of one or more S-NSSAIs that are pending as the network slice-specific authentication and authorization procedure is not completed.
The network shall include the Negotiated NB-N1 mode DRX parameters IE if the requested NB-N1 mode DRX parameters IE was included in the REGISTRATION REQUEST message.
If the UE supports Extended rejected NSSAI, the network may include this IE to inform the UE of one or more S-NSSAIs that were included in the requested NSSAI in the REGISTRATION REQUEST message but were rejected by the network.
The network shall include this IE if the UUAA procedure is triggered for the UE supporting UAS services. The network may include this IE if there is a valid successful UUAA result for the UE in the UE 5GMM context upon a registration for UAS services is requested from the UE.
This IE may be included by an allowed PLMN to assign a new "list of PLMN(s) to be used in disaster condition" associated with the serving PLMN to the UE.
This IE is included to indicate the forbidden TAI(s) to be stored in the list of "5GS forbidden tracking areas for roaming". This IE is included only if the message is sent via satellite NG-RAN access.
This IE is included to indicate the forbidden TAI(s) to be stored in the list of "5GS forbidden tracking areas for regional provision of service". This IE is included only if the message is sent via satellite NG-RAN access.
If the UE supports Extended CAG information list, the network may include this IE to assign a new "CAG information list" to the UE or delete the "CAG information list" at the UE side.
If the UE has set the NSAG bit to "NSAG supported" in the 5GMM capability IE of the REGISTRATION REQUEST message over 3GPP access, the network may include this IE to provide NSAG information to the UE. Otherwise, the network shall not include this IE (see the 'comprehension required' scheme in subclause 11.2.5 of TS 24.007).
This information element may be included only if the network knows that the UE will not treat this IE as unknown 'comprehension required' IE. Otherwise, the network shall not include this IE (see the 'comprehension required' scheme in subclause 11.2.5 of TS 24.007).
In this version of the specification, only the transfer of the information elements specified in Table 8.2.7.54.1.1 is supported in the Registration accept type 6 IE container information element in the present message. For the handling of an information element with an IEI not listed in Table 8.2.7.54.1.1, i.e., with an IEI unknown in the Registration accept type 6 IE container information element, see subclause 7.6.4.1.
The network shall include this IE if the UE supports LADN per DNN and S-NSSAI and there are valid LADN service area(s) for the subscribed DNN(s) of the UE and S-NSSAI associated with the LADN in the current registration area.
This IE may be included to provide information related to the RAN timing synchronization to a UE which has set the Reconnection to the network due to RAN timing synchronization status change (RANtiming) bit to "Reconnection to the network due to RAN timing synchronization status change supported" in the 5GMM capability IE of the REGISTRATION REQUEST message.
The network may include this IE to inform to the UE about the authorization status of the UE whether to operate as an MBSR or to operate not as an MBSR but to operate as a UE.
This IE may be sent by the UE. If this IE is sent, the contents of this IE indicates the UE acknowledgement of successful reception of the SOR transparent container IE in the REGISTRATION ACCEPT message. This IE shall indicate the ME support of SOR-CMCI.