Section: 5.5.3.2.2 Normal and periodic tracking area updating procedure initiation
Content: The UE in state EMM-REGISTERED shall initiate the tracking area updating procedure by sending a TRACKING AREA UPDATE REQUEST message to the MME, a) when the UE detects that the current TAI is not in the list of tracking areas that the UE previously registered in the MME, unless the UE is configured for "AttachWithIMSI" as specified in 3GPP TS 24.368[ Non-Access Stratum (NAS) configuration Management Object (MO) ]  [15A] or 3GPP TS 31.102[ Characteristics of the Universal Subscriber Identity Module (USIM) application ]  [17] and is entering a tracking area in a new PLMN that is neither the registered PLMN nor in the list of equivalent PLMNs; b) when the periodic tracking area updating timer T3412 expires and the UE is not registered for emergency services (see subclause 5.3.5); c) when the UE enters EMM-REGISTERED.NORMAL-SERVICE and the UE's TIN indicates "P-TMSI"; d) when the UE performs an inter-system change from S101 mode to S1 mode and has no user data pending; e) when the UE receives an indication from the lower layers that the RRC connection was released with cause "load balancing TAU required"; f) when the UE deactivated EPS bearer context(s) locally while in EMM-REGISTERED, because it could not establish a NAS signalling connection, and then returns to EMM-REGISTERED.NORMAL-SERVICE and no EXTENDED SERVICE REQUEST message, CONTROL PLANE SERVICE REQUEST message or DETACH REQUEST message with detach type is "EPS detach" or "combined EPS/IMSI detach" is pending to be sent by the UE; g) when the UE changes any one of the UE network capability information, the MS network capability information or the N1 UE network capability information; h) when the UE changes the UE specific DRX parameter (in WB-S1 mode or NB-S1 mode); i) when the UE receives an indication of "RRC Connection failure" from the lower layers and has no signalling or user uplink data pending (i.e. when the lower layer requests NAS signalling connection recovery); j) when the UE enters S1 mode after 1xCS fallback or 1xSRVCC; k) when due to manual CSG selection the UE has selected a CSG cell whose CSG identity and associated PLMN identity are not included in the UE's Allowed CSG list or in the UE's Operator CSG list; l) when the UE reselects an E-UTRAN cell while it was in GPRS READY state or PMM-CONNECTED mode; m) when the UE supports SRVCC to GERAN or UTRAN or supports vSRVCC to UTRAN and changes the mobile station classmark 2 or the supported codecs, or the UE supports SRVCC to GERAN and changes the mobile station classmark 3; n) when the UE changes the radio capability for GERAN, or cdma2000® or both; o) when the UE's usage setting or the voice domain preference for E-UTRAN change in the UE; NOTE 1: For the change of UE's usage setting or the voice domain preference for E-UTRAN which results in disabling UE's E-UTRA capability, the UE can skip sending TRACKING AREA UPDATE REQUEST message and directly perform disabling of UE's E-UTRA capability. p) when the UE activates mobility management for IMS voice termination as specified in 3GPP TS 24.008[ Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 ]  [13], annex P.2, and the TIN indicates "RAT-related TMSI"; q) when the UE performs an inter-system change from A/Gb mode to S1 mode and the TIN indicates "RAT-related TMSI", but the UE is required to perform tracking area updating for IMS voice termination as specified in 3GPP TS 24.008[ Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 ]  [13], annex P.4; r) upon reception of a paging indication using S-TMSI and the UE is in state EMM-REGISTERED.ATTEMPTING-TO-UPDATE; NOTE 2: As an implementation option, the MUSIM UE is allowed to not respond to paging based on the information available in the paging message, e.g. voice service indication. s) when the UE needs to update the network with EPS bearer context status due to local de-activation of EPS bearer context(s) as specified in clause 6.5.1.4A; t) when the UE needs to request the use of PSM or needs to stop the use of PSM; u) when the UE needs to request the use of eDRX or needs to stop the use of eDRX; v) when a change in the eDRX usage conditions at the UE requires different extended DRX parameters; w) when a change in the PSM usage conditions at the UE requires a different timer T3412 value or different timer T3324 value; NOTE 3: A change in the PSM or eDRX usage conditions at the UE can include e.g. a change in the UE configuration, a change in requirements from upper layers or the battery running low at the UE. x) when the CIoT EPS optimizations the UE needs to use, change in the UE; y) when the Default_DCN_ID value changes, as specified in 3GPP TS 24.368[ Non-Access Stratum (NAS) configuration Management Object (MO) ]  [15A] or in USIM file NASCONFIG as specified in 3GPP TS 31.102[ Characteristics of the Universal Subscriber Identity Module (USIM) application ]  [17]; NOTE 4: The tracking area updating procedure is initiated after deleting the DCN-ID list as specified in annex C. z) when the UE performs inter-system change from N1 mode to S1 mode in EMM-IDLE mode, the UE operates in single-registration mode, and conditions specified in 3GPP TS 24.501[ Non-Access-Stratum (NAS) protocol for 5G System (5GS); Stage 3 ]  [54] apply; za) when the UE in EMM-IDLE mode changes the radio capability for E-UTRAN; zb) when the UE needs to request new ciphering keys for ciphered broadcast assistance data; zc) when the UE in EMM-IDLE mode changes the radio capability for NG-RAN; zd) when the UE performs inter-system change from N1 mode to S1 mode in EMM-CONNECTED mode; ze) in WB-S1 mode, when the UE has received a UE radio capability ID deletion indication IE set to "Network-assigned UE radio capability IDs deletion requested"; zf) when the UE needs to use the WUS assistance, stop to use the WUS assistance, or change the conditions for using the WUS assistance; zg) when the MUSIM UE needs to request an IMSI Offset value as specified in 3GPP TS 23.401[ General Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial Radio Access Network (E-UTRAN) access ]  [10] that is used for deriving the paging occasion as specified in 3GPP TS 36.304[ Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) procedures in idle mode ]  [21]; or zh) when the UE in EMM-IDLE mode needs to inform the network that a UE radio capability information update is required due to a cell change between E-UTRAN and satellite E-UTRAN cells. If case b) is the only reason for initiating the normal and periodic tracking area updating procedure, the UE shall indicate "periodic updating" in the EPS update type IE; otherwise the UE shall indicate "TA updating". For cases n, za, zc and zh the UE shall include a UE radio capability information update needed IE in the TRACKING AREA UPDATE REQUEST message. NOTE 4a: For cases n, za, zc and zh if the UE supports RACS irrespective whether the UE has an applicable UE radio capability ID for the new UE radio configuration in the selected PLMN the UE radio capability information update needed IE is included in the TRACKING AREA UPDATE REQUEST message. If the UE is in the EMM-CONNECTED mode and the UE changes the radio capability for E-UTRAN or for NG-RAN, the UE may locally release the established NAS signalling connection and enter the EMM-IDLE mode. Then, the UE shall initiate the tracking area updating procedure including a UE radio capability information update needed IE in the TRACKING AREA UPDATE REQUEST message. For case l, if the TIN indicates "RAT-related TMSI", the UE shall set the TIN to "P-TMSI" before initiating the tracking area updating procedure. For case r, the "active" flag in the EPS update type IE shall be set to 1. If a UE is only using EPS services with control plane CIoT EPS optimization, the "signalling active" flag in the Additional update type IE shall be set to 1. If the UE is using only control plane CIoT EPS optimization, the case i only applies to the case that the UE has indicated to the network that subsequent to the uplink data transmission a downlink data transmission is expected during the transport of uplink user data via the control plane procedure (see clause 6.6.4). If the UE has to request resources for ProSe direct discovery or Prose direct communication (see 3GPP TS 36.331[ Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification ]  [22]), then the UE shall set the "active" flag to 1 in the TRACKING AREA UPDATE REQUEST message. If the UE does not have any established PDN connection, and the inter-system change from N1 mode to S1 mode is not due to emergency services fallback, the "active" flag in the EPS update type IE shall be set to 0. When the UE has user data pending and performs an inter-system change from S101 mode to S1 mode to a tracking area included in the TAI list stored in the UE, the UE shall perform a service request procedure instead of a tracking area updating procedure. When initiating a tracking area updating procedure while in S1 mode, the UE shall use the current EPS NAS integrity key to integrity protect the TRACKING AREA UPDATE REQUEST message, unless the UE is performing inter-system change from N1 mode to S1 mode. In order to indicate its UE specific DRX parameter for WB-S1 mode while in E-UTRAN coverage, the UE shall send the TRACKING AREA UPDATE REQUEST message containing the UE specific DRX parameter in the DRX parameter IE to the network, with the exception of the case if the UE had indicated its DRX parameter for WB-S1 mode (3GPP TS 24.008[ Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 ]  [13]) to the network while in GERAN or UTRAN coverage. In this case, when the UE enters E-UTRAN coverage and initiates a tracking area updating procedure, the UE shall not include the UE specific DRX parameter in the DRX parameter IE in the TRACKING AREA UPDATE REQUEST message. In NB-S1 mode, a UE that wishes to use or change a UE specific DRX parameter in NB-S1 mode shall include its requested value in every TRACKING AREA UPDATE REQUEST message except when initiating the periodic tracking area updating procedure. If the UE supports eDRX and requests the use of eDRX, the UE shall include the extended DRX parameters IE in the TRACKING AREA UPDATE REQUEST message. If the UE supports PSM and requests the use of PSM, the UE shall include the T3324 value IE with a requested timer value in the TRACKING AREA UPDATE REQUEST message. When the UE includes the T3324 value IE and the UE indicates support for extended periodic timer value in the MS network feature support IE, it may also include the T3412 extended value IE to request a particular T3412 value to be allocated. If a UE supporting CIoT EPS optimizations in NB-S1 mode initiates the tracking area updating procedure for EPS services and "SMS only", the UE shall indicate "SMS only" in the Additional update type IE and shall set the EPS update type IE to "TA updating". If the UE supports enhanced discontinuous coverage, then the UE shall set the EDC bit to "Enhanced discontinuous coverage supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. If the network has indicated support for enhanced discontinuous coverage and needs to indicate upcoming availability due to discontinuous coverage, the UE shall include the Unavailability information IE in the TRACKING AREA UPDATE REQUEST message. The UE shall set the unavailability type in the Unavailability information IE to "unavailability due to discontinuous coverage". The UE may include the unavailability period duration or the time to the start of the unavailability period or both in the Unavailability information IE. If the UE supports S1-U data transfer and multiple user plane radio bearers (see 3GPP TS 36.306[ Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE) radio access capabilities ]  [44], 3GPP TS 36.331[ Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification ]  [22]) in NB-S1 mode, then the UE shall set the Multiple DRB support bit to "Multiple DRB supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. If the UE is in NB-S1 mode, then the UE shall set the Control plane CIoT EPS optimization bit to "Control plane CIoT EPS optimization supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. If the UE is capable of NB-N1 mode, then the UE shall set the Control plane CIoT 5GS optimization bit to "Control plane CIoT 5GS optimization supported" in the N1 UE network capability IE of the TRACKING AREA UPDATE REQUEST message. If the UE supports control plane MT-EDT, then the UE shall set the CP-MT-EDT bit to "Control plane Mobile Terminated-Early Data Transmission supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. If the UE supports user plane MT-EDT, then the UE shall set the UP-MT-EDT bit to "User plane Mobile Terminated-Early Data Transmission supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. If the UE supports EPS-UPIP, the UE shall set the EPS-UPIP bit to "EPS-UPIP supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. If the UE has to request resources for V2X communication over PC5 (see 3GPP TS 23.285[ Architecture enhancements for V2X services ]  [47]), then the UE shall set the "active" flag to 1 in the TRACKING AREA UPDATE REQUEST message. After sending the TRACKING AREA UPDATE REQUEST message to the MME, the UE shall start timer T3430 and enter state EMM-TRACKING-AREA-UPDATING-INITIATED (see example in figure 5.5.3.2.2.1). If timer T3402 is currently running, the UE shall stop timer T3402. If timer T3411 is currently running, the UE shall stop timer T3411. If timer T3442 is currently running, the UE shall stop timer T3442. For all cases except cases z and zd: 1) if the UE supports neither A/Gb mode nor Iu mode, the UE shall include a valid GUTI in the Old GUTI IE in the TRACKING AREA UPDATE REQUEST message. In addition, the UE shall include Old GUTI type IE with GUTI type set to "Native GUTI"; or 2) if the UE supports A/Gb mode or Iu mode or both, the UE shall handle the Old GUTI IE as follows: - If the TIN indicates "P-TMSI" and the UE holds a valid native P-TMSI and RAI, the UE shall map the P-TMSI and RAI into the Old GUTI IE, and include Old GUTI type IE with GUTI type set to "Mapped GUTI". If a P-TMSI signature is associated with the P-TMSI, the UE shall include it in the Old P-TMSI signature IE. Additionally, if the UE holds a valid GUTI, the UE shall indicate the GUTI in the Additional GUTI IE. NOTE 5: The mapping of the P-TMSI and RAI to the GUTI is specified in 3GPP TS 23.003[ Numbering, addressing and identification ]  [2]. - If the TIN indicates "GUTI" or "RAT-related TMSI" and the UE holds a valid GUTI, the UE shall indicate the GUTI in the Old GUTI IE, and include Old GUTI type IE with GUTI type set to "Native GUTI". If a UE has established PDN connection(s) and uplink user data pending to be sent via user plane when it initiates the tracking area updating procedure, or uplink signalling not related to the tracking area updating procedure when the UE does not support control plane CIoT EPS optimization, it may set the "active" flag in the TRACKING AREA UPDATE REQUEST message to indicate the request to establish the user plane to the network and to keep the NAS signalling connection after the completion of the tracking area updating procedure. If a UE is using EPS services with control plane CIoT EPS optimization and has user data pending to be sent via control plane over MME but no user data pending to be sent via user plane, or uplink signalling not related to the tracking area updating procedure, the UE may set the "signalling active" flag in the TRACKING AREA UPDATE REQUEST message to indicate the request to keep the NAS signalling connection after the completion of the tracking area updating procedure. For all cases except cases z and zd, if the UE has a current EPS security context, the UE shall include the eKSI (either KSIASME or KSISGSN) in the NAS Key Set Identifier IE in the TRACKING AREA UPDATE REQUEST message. Otherwise, the UE shall set the NAS Key Set Identifier IE to the value "no key is available". If the UE has a current EPS security context, the UE shall integrity protect the TRACKING AREA UPDATE REQUEST message with the current EPS security context. Otherwise the UE shall not integrity protect the TRACKING AREA UPDATE REQUEST message. When the tracking area updating procedure is initiated in EMM-IDLE mode to perform an inter-system change from A/Gb mode or Iu mode to S1 mode and the TIN is set to "P-TMSI", the UE shall include the GPRS ciphering key sequence number applicable for A/Gb mode or Iu mode and a nonceUE in the TRACKING AREA UPDATE REQUEST message. When the tracking area updating procedure is initiated in EMM-CONNECTED mode to perform an inter-system change from A/Gb mode or Iu mode to S1 mode, the UE shall derive the EPS NAS keys from the mapped K'ASME using the selected NAS algorithms, nonceMME and KSISGSN (to be associated with the mapped K'ASME) provided by lower layers as indicated in 3GPP TS 33.401[ 3GPP System Architecture Evolution (SAE); Security architecture ]  [19]. The UE shall reset both the uplink and downlink NAS COUNT counters of the mapped EPS security context which shall be taken into use. If the UE has a non-current native EPS security context, the UE shall include the KSIASME in the Non-current native NAS key set identifier IE and its associated GUTI, as specified above, either in the Old GUTI IE or in the Additional GUTI IE of the TRACKING AREA UPDATE REQUEST message. The UE shall set the TSC flag in the Non-current native NAS key set identifier IE to "native security context". For the case z, if upper layers have indicated that IMS signalling or IMS emergency signalling was already ongoing in N1 mode before performing the inter-system change from N1 mode to S1 mode, or if the inter-system change from N1 mode to S1 mode is due to emergency services fallback, the "active" flag in the EPS update type IE shall be set to 1. For the case z, the TRACKING AREA UPDATE REQUEST message shall be integrity protected using the 5G NAS security context available in the UE. If there is no valid 5G NAS security context available in the UE, the TRACKING AREA UPDATE REQUEST message shall be sent without integrity protection. The UE shall include a GUTI, mapped from 5G-GUTI (see 3GPP TS 23.501[ System architecture for the 5G System (5GS) ]  [58] and 3GPP TS 23.003[ Numbering, addressing and identification ]  [2]), in the Old GUTI IE in the TRACKING AREA UPDATE REQUEST message. In addition, the UE shall include Old GUTI type IE with GUTI set to "Native GUTI", and the UE shall include a UE status IE with a 5GMM registration status set to "UE is in 5GMM-REGISTERED state". Additionally, if the UE holds a valid GUTI, the UE shall indicate the GUTI in the Additional GUTI IE. NOTE 6: The value of the EMM registration status included by the UE in the UE status IE is not used by the MME. For the case zd, the TRACKING AREA UPDATE REQUEST message shall be integrity protected using the mapped EPS security context as derived when triggering the handover to E-UTRAN (see clause 4.4.2.2). The UE shall include a GUTI, mapped from 5G-GUTI (see 3GPP TS 23.501[ System architecture for the 5G System (5GS) ]  [58] and 3GPP TS 23.003[ Numbering, addressing and identification ]  [2]), in the Old GUTI IE in the TRACKING AREA UPDATE REQUEST message. In addition, the UE shall include Old GUTI type IE with GUTI set to "Native GUTI", and the UE shall include a UE status IE with a 5GMM registration status set to "UE is in 5GMM-REGISTERED state". Additionally, if the UE holds a valid GUTI, the UE shall indicate the GUTI in the Additional GUTI IE. If the UE has a non-current native EPS security context, the UE shall include the KSIASME in the Non-current native NAS key set identifier IE of the TRACKING AREA UPDATE REQUEST message. The UE shall set the TSC flag in the Non-current native NAS key set identifier IE to "native security context". NOTE 7: The value of the EMM registration status included by the UE in the UE status IE is not used by the MME. When the tracking area updating procedure is initiated in EMM-IDLE mode, the UE may also include an EPS bearer context status IE in the TRACKING AREA UPDATE REQUEST message, indicating which EPS bearer contexts are active in the UE. The UE shall include the EPS bearer context status IE in TRACKING AREA UPDATE REQUEST message: a) for the case f; b) for the case s; c) for the case z; d) if the UE has established PDN connection(s) of "non IP" or Ethernet PDN type; and e) if the UE: 1) locally deactivated at least one dedicated EPS bearer context upon an inter-system mobility from WB-S1 mode to NB-S1 mode in EMM-IDLE mode; 2) locally deactivated at least one dedicated EPS bearer context upon an inter-system change from WB-N1 mode to NB-S1 mode in EMM-IDLE mode for the UE operating in single-registration mode (see clause 6.4.2.1); or 3) locally deactivated at least one default EPS bearer context upon an inter-system change from N1 mode to NB-S1 mode in EMM-IDLE mode for the UE operating in single-registration mode (see clause 6.5.0). If the UE initiates the first tracking area updating procedure following an attach in A/Gb mode or Iu mode, the UE shall include a UE radio capability information update needed IE in the TRACKING AREA UPDATE REQUEST message. If the UE initiates the first tracking area updating procedure following an initial registration in N1 mode and the UE is operating in the single-registration mode, the UE shall include a UE radio capability information update needed IE in the TRACKING AREA UPDATE REQUEST message. For all cases except case b, if the UE supports SRVCC to GERAN/UTRAN, the UE shall set the SRVCC to GERAN/UTRAN capability bit in the MS network capability IE to "SRVCC from UTRAN HSPA or E-UTRAN to GERAN/UTRAN supported". For all cases except case b, if the UE supports vSRVCC from S1 mode to Iu mode, then the UE shall set the H.245 after handover capability bit in the UE network capability IE to "H.245 after SRVCC handover capability supported" and additionally set the SRVCC to GERAN/UTRAN capability bit in the MS network capability IE to "SRVCC from UTRAN HSPA or E-UTRAN to GERAN/UTRAN supported" in the TRACKING AREA UPDATE REQUEST message. For all cases except case b, if the UE supports ProSe direct discovery, then the UE shall set the ProSe bit to "ProSe supported" and set the ProSe direct discovery bit to "ProSe direct discovery supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. For all cases except case b, if the UE supports ProSe direct communication, then the UE shall set the ProSe bit to "ProSe supported" and set the ProSe direct communication bit to "ProSe direct communication supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. For all cases except case b, if the UE supports acting as a ProSe UE-to-network relay, then the UE shall set the ProSe bit to "ProSe supported" and set the ProSe UE-to-network relay bit to "acting as a ProSe UE-to-network relay supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. If the UE supports NB-S1 mode, Non-IP or Ethernet PDN type, N1 mode, UAS services, URSP provisioning in EPS or if the UE supports DNS over (D)TLS (see 3GPP TS 33.501[ Security architecture and procedures for 5G System ]  [24]), then the UE shall support the Extended protocol configuration options IE. NOTE 8: Support of DNS over (D)TLS is based on the informative requirements as specified in 3GPP TS 33.501[ Security architecture and procedures for 5G System ]  [24]. For all cases except case b, if the UE supports the Extended protocol configuration options IE, then the UE shall set the ePCO bit to "extended protocol configuration options supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. If the UE supports providing PDU session ID in the Protocol configuration options IE or the Extended protocol configuration option IE when its N1 mode capability is disabled, then the UE shall set the ePCO bit to "extended protocol configuration options supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. For all cases except case b, if the UE supports V2X communication over E-UTRAN-PC5, then the UE shall set the V2X PC5 bit to "V2X communication over E-UTRAN-PC5 supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. For all cases except case b, if the UE supports V2X communication over NR-PC5, then the UE shall set the V2X NR-PC5 bit to "V2X communication over NR-PC5 supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. For all cases except case b, if the UE supports the restriction on use of enhanced coverage, then the UE shall set the RestrictEC bit to "Restriction on use of enhanced coverage supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. For all cases except case b, if the UE supports the control plane data back-off timer T3448, the UE shall set the CP backoff bit to "backoff timer for transport of user data via the control plane supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. For all cases except case b, if the UE supports dual connectivity with NR, then the UE shall set the DCNR bit to "dual connectivity with NR supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message and shall include the UE additional security capability IE in the TRACKING AREA UPDATE REQUEST message. For all cases except case b, if the UE supports SGC, then the UE shall set the SGC bit to "service gap control supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. For all cases except case b, if the UE supports signalling for a maximum number of 15 EPS bearer contexts, then the UE shall set the 15 bearers bit to "Signalling for a maximum number of 15 EPS bearer contexts supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. For all cases except case b, if the MUSIM UE supports the NAS signalling connection release, then the UE shall set the NAS signalling connection release bit to "NAS signalling connection release supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message otherwise the UE shall not set the NAS signalling connection release bit to "NAS signalling connection release supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. For all cases except case b, if the MUSIM UE supports the paging indication for voice services, then the UE shall set the paging indication for voice services bit to "paging indication for voice services supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message otherwise the UE shall not set the paging indication for voice services bit to "paging indication for voice services supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. For all cases except case b, if the MUSIM UE supports the reject paging request, then the UE shall set the reject paging request bit to "reject paging request supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message otherwise the UE shall not set the reject paging request bit to "reject paging request supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. For all cases except case b, if the MUSIM UE sets: - the reject paging request bit to "reject paging request supported"; - the NAS signalling connection release bit to "NAS signalling connection release supported"; or - both of them; and supports the paging restriction, then the UE shall set the paging restriction bit to "paging restriction supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message otherwise the UE shall not set the paging restriction bit to "paging restriction supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. For all cases except case b, if the MUSIM UE supports the paging timing collision control, then the UE shall set the paging timing collision control bit to "paging timing collision control supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message otherwise the UE shall not set the paging timing collision control bit to "paging timing collision control supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. For all cases except cases b and zb, if the UE supports ciphered broadcast assistance data and the UE needs to obtain new ciphering keys, the UE shall include the Additional information requested IE with the CipherKey bit set to "ciphering keys for ciphered broadcast assistance data requested" in the TRACKING AREA UPDATE REQUEST message. For case ee, the UE shall include the Additional information requested IE with the CipherKey bit set to "ciphering keys for ciphered broadcast assistance data requested" in the TRACKING AREA UPDATE REQUEST message. For case a, if the UE supports ciphered broadcast assistance data and the UE detects entering a tracking area for which one or more ciphering keys stored at the UE is not applicable, the UE should include the Additional information requested IE with the CipherKey bit set to "ciphering keys for ciphered broadcast assistance data requested" in the TRACKING AREA UPDATE REQUEST message. For case b, if the UE supports ciphered broadcast assistance data and the remaining validity time for one or more ciphering keys stored at the UE is less than timer T3412, the UE should include the Additional information requested IE with the CipherKey bit set to "ciphering keys for ciphered broadcast assistance data requested" in the TRACKING AREA UPDATE REQUEST message. For all cases except case b, if the UE supports N1 mode for 3GPP access, the UE shall set the N1mode bit to "N1 mode for 3GPP access supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message and shall include the UE additional security capability IE in the TRACKING AREA UPDATE REQUEST message. For all cases except case b, in WB-S1 mode, if the UE supports RACS the UE shall set the RACS bit to "RACS supported" in the UE network capability IE of the TRACKING AREA UPDATE REQUEST message. For cases n, za, zc and zh, in WB-S1 mode, if the UE supports RACS and the UE has an applicable UE radio capability ID for the new UE radio configuration in the selected PLMN, the UE shall set the URCIDA bit to "UE radio capability ID available" in the UE radio capability ID availability IE of the TRACKING AREA UPDATE REQUEST message. For all cases except cases b, n, za, zc and zh, in WB-S1 mode, if the UE has an applicable UE radio capability ID for the current UE radio configuration in the selected PLMN, the UE shall set the URCIDA bit to "UE radio capability ID available" in the UE radio capability ID availability IE of the TRACKING AREA UPDATE REQUEST message. For all cases except case b, if the UE supports WUS assistance, then the UE shall set the WUSA bit to "WUS assistance supported" in the UE network capability IE, and if the UE is not attaching for emergency bearer services, the UE may include its UE paging probability information in the Requested WUS assistance information IE in the TRACKING AREA UPDATE REQUEST message. For all cases except case a, except case b, for a MUSIM UE if the UE needs to indicate an IMSI offset value to the network and the network has indicated to the UE that it supports paging timing collision control, the UE shall include the IMSI offset value in the Requested IMSI offset IE in the TRACKING AREA UPDATE REQUEST message. For case a, MUSIM UE may include the IMSI offset value in the Requested IMSI offset IE in the TRACKING AREA UPDATE REQUEST message even if the network has not indicated that it supports paging timing collision control. If the network supports the NAS signalling connection release and the MUSIM UE requests the network to release the NAS signalling connection, the UE shall set Request type to "NAS signalling connection release" in the UE request type IE and, if the network supports the paging restriction, may set the paging restriction preference in the Paging restriction IE in the TRACKING AREA UPDATE REQUEST message. In addition, the UE shall - set the "active" flag to 0 in the EPS update type IE; and - set the "signalling active" flag to 0 in the Additional update type IE, if the Additional update type IE is included. NOTE 9: If the network has already indicated support for NAS signalling connection release in the current stored tracking area list and the UE doesn't have a PDN connection for emergency bearer services established, the MUSIM UE is allowed to request the network to release the NAS signalling connection during tracking area updating procedure that is due to mobility to a tracking area outside the current tracking area list even before detecting whether the network supports the NAS signalling connection release in the new tracking area. NOTE 10: If the network has already indicated support for paging restriction in the current stored tracking area list and the UE doesn't have a PDN connection for emergency bearer services established, the MUSIM UE is allowed to include paging restriction together with the request to the network to release the NAS signalling connection during tracking area updating procedure that is due to mobility to a tracking area outside the current tracking area list even before detecting whether the network supports the paging restriction in the new tracking area. Figure 5.5.3.2.2.1: Tracking area updating procedure