Section: 4.4.1 Location updating procedure
Content: The location updating procedure is a general procedure which is used for the following purposes: - normal location updating (described in this subclause); - periodic updating (see subclause 4.4.2); or - IMSI attach (see subclause 4.4.3). The normal location updating procedure is used to update the registration of the actual Location Area of a mobile station in the network. The location updating type information element in the LOCATION UPDATING REQUEST message shall indicate normal location updating. The conditions under which the normal location updating procedure is used by a mobile station in the MM IDLE state are defined for each service state in subclause 4.2.2. Only applicable for mobile stations supporting VGCS listening or VBS listening: A mobile station in RR group receive mode is in the MM IDLE state, substate RECEIVING GROUP CALL (NORMAL SERVICE) or RECEIVING GROUP CALL (LIMITED SERVICE). To perform a location updating, the MS in RR group receive mode shall leave the group receive mode, establish an independent dedicated RR connection to perform the location updating as described above and return to the RR group receive mode afterwards. The MS shall also start the normal location updating procedure: a) if the network indicates that the mobile station is unknown in the VLR as a response to MM connection establishment request; b) void c) when the MS, configured to use CS fallback and SMS over SGs, or SMS over SGs only, enters a GERAN or UTRAN cell in network operation mode II and timer T3423 has expired or is in the GERAN or UTRAN cell in network operation mode II when timer T3423 expires; NOTE 1: Timer T3423 is specified in 3GPP TS 24.301[ Non-Access-Stratum (NAS) protocol for Evolved Packet System (EPS); Stage 3 ]  [120]. d) when the MS, configured to use CS fallback and SMS over SGs, or SMS over SGs only, enters a GERAN or UTRAN cell after intersystem change from S1 mode to Iu or A/Gb mode, if timer T3346 is running, and the location area of the current cell is the same as the stored location area; NOTE 2: If inter-system change is due to a mobile originating CS call, the location updating procedure can be performed after the RR connection is released unless the MS moves back to E-UTRAN. e) when the MS is both IMSI attached for GPRS and non-GPRS services and enters a new routing area where the network operates in network operation mode I and timer T3346 is running. f) when the network is operating in network operation mode I, timer T3346 is running, timer T3246 is not running, and due to manual CSG selection the MS has selected a CSG cell whose CSG identity and associated PLMN identity are not included in the Allowed CSG list or in the Operator CSG list of the MS; g) when due to a manual CSG selection the MS has selected a CSG cell whose CSG identity and associated PLMN identity are not included in the MS's Allowed CSG list or in the MS's Operator CSG list; h) when the network is operating in network operation mode I, T3346 is running, update status is not U1 UPDATED and the user manually selects the current PLMN; or i) when the MS is configured to use CS fallback and SMS over SGs, or SMS over SGs only, and the TIN indicates "GUTI", enters a GERAN or UTRAN cell after intersystem change from S1 mode to Iu or A/Gb mode in NMO II and timer T3412 is not running. If the MS, configured to use CS fallback and SMS over SGs, enters a GERAN or UTRAN cell, after intersystem change from S1 mode to Iu or A/Gb mode due to CS fallback, and the location area of the current cell is not available, the MS may initiate the location updating procedure. When the MS supporting N1 mode in MS operation modes A or B moves from NG-RAN coverage to GERAN coverage, or from NG-RAN coverage to UTRAN coverage, and the network operates in network operation mode II, the MS may intiate the normal location updating procedure. To limit the number of consecutive unsuccessful location updating attempts made, an attempt counter is used. The detailed handling of the attempt counter is described in subclauses 4.4.4.5 to 4.4.4.9. The mobile equipment shall contain a list of "forbidden location areas for roaming", as well as a list of "forbidden location areas for regional provision of service". These lists shall be erased when the MS is switched off or when the SIM/USIM is removed, and periodically (with period in the range 12 to 24 hours). When the lists are erased, the MS performs a cell selection according to 3GPP TS 43.022[ None ]  [82] and 3GPP TS 25.304[ None ]  [98]. The location area identification received on the BCCH that triggered the location updating request shall be added to the suitable list whenever a LOCATION AREA UPDATING REJECT message is received with the cause "Roaming not allowed in this location area", "Location Area not allowed", or "No suitable cells in Location Area". The lists shall accommodate each 10 or more location area identifications. When the list is full and a new entry has to be inserted, the oldest entry shall be deleted. In a shared network, the MS shall choose one of the PLMN identities as specified in 3GPP TS 23.122[ Non-Access-Stratum (NAS) functions related to Mobile Station (MS) in idle mode ]  [14]. The MS shall construct the Location Area Identification of the cell from this chosen PLMN identity and the LAC received on the BCCH. If the constructed LAI is different from the stored LAI, the MS shall initiate the location updating procedure. For: - a shared GERAN, in A/Gb mode, the chosen PLMN identity shall be indicated to the GERAN in the LOCATION UPDATING REQUEST message using the Skip Indicator IE as specified in subclause 10.3.1. - a shared UTRAN, the chosen PLMN identity shall be indicated to the UTRAN in the RRC INITIAL DIRECT TRANSFER message (see 3GPP TS 25.331[ None ]  [23c]). For GERAN Iu mode, network sharing is not supported. Whenever a LOCATION UPDATING REJECT message with the cause "PLMN not allowed" is received by the MS, the PLMN identity used to construct the LAI which triggered the location updating procedure shall be stored in the "forbidden PLMN list" and if the MS is configured to use timer T3245 (see 3GPP TS 24.368[ Non-Access Stratum (NAS) configuration Management Object (MO) ]  [135] or 3GPP TS 31.102[ Characteristics of the Universal Subscriber Identity Module (USIM) application ]  [112]) then the MS shall start timer T3245 and proceed as described in subclause 4.1.1.6. Whenever a LOCATION UPDATING REJECT message is received by the MS with the cause "Roaming not allowed in this location area", "Location Area not allowed", or "No suitable cells in Location Area", the constructed LAI which triggered the location updating procedure shall be stored in the suitable list. The cell selection processes in the different states are described in 3GPP TS 43.022[ None ]  [82] and 3GPP TS 45.008[ None ]  [34]. The location updating procedure is always initiated by the mobile station. In the case that the mobile station is initiating an emergency call but, due to cell re-selection or redirection by the network, it moves to a different LAI then the mobile station may delay the location updating procedure in the new LA until after the emergency call is completed.