Section: 4.7.5.2.3 Combined routing area updating procedure accepted by the network
Content: Depending on the value of the update result IE received in the ROUTING AREA UPDATE ACCEPT message, two different cases can be distinguished: Case 1) The update result IE value indicates "combined RA/LA": Routing and location area updating is successful; Case 2) The update result IE value indicates "RA only": Routing area updating is successful, but location area updating is not successful. A ROUTING AREA UPDATE COMPLETE message shall be returned to the network if the ROUTING AREA UPDATE ACCEPT message containsany of: - a P-TMSI and/or a TMSI; - Receive N-PDU Numbers (see 3GPP TS 44.065[ Mobile Station (MS) - Serving GPRS Support Node (SGSN);  Subnetwork Dependent Convergence Protocol (SNDCP) ]  [78] and 3GPP TS 25.322[ None ]  [19b]); or - a request for the provision of Inter RAT handover information. If Receive N-PDU Numbers were included, the Receive N-PDU Numbers that are valid in the MS shall be included in the ROUTING AREA UPDATE COMPLETE message. If the network has requested the provision of Inter RAT handover information the MS shall return a ROUTING AREA UPDATE COMPLETE message including the Inter RAT handover information IE, as applicable, to the network. In Iu mode, if the network wishes to prolong the PS signalling connection (for example, if the mobile station has indicated "follow-on request pending" in ROUTING AREA UPDATE REQUEST message) the network shall indicate the "follow-on proceed" in the ROUTING AREA UPDATE ACCEPT message. If the network wishes to release the PS signalling connection, the network shall indicate "no follow-on proceed" in the ROUTING AREA UPDATE ACCEPT message. After that in Iu mode, the mobile station shall act according to the follow-on proceed flag included in the Update result information element in the ROUTING AREA UPDATE ACCEPT message (see subclause 4.7.13). If the network supports CS Fallback, and the mobile station has indicated support of EMM combined procedures in MS network capability, the network shall indicate in the Update result IE in the ROUTING AREA UPDATE ACCEPT message that ISR is not activated. 4.7.5.2.3.1 Combined routing area updating successful The description for normal routing area update as specified in subclause 4.7.5.1.3 shall be followed. In addition, the following description for location area updating applies. The handling at the receipt of the ROUTING AREA UPDATE ACCEPT depends on the value received in the update result IE as specified below. The TMSI reallocation may be part of the combined routing area updating procedure. The TMSI allocated is then included in the ROUTING AREA UPDATE ACCEPT message together with the location area identification (LAI). The network shall, in this case, change to state GMM-COMMON-PROCEDURE-INITIATED and shall start the timer T3350 as described in subclause 4.7.6. The MS, receiving a ROUTING AREA UPDATE ACCEPT message, stores the received location area identification, stops timer T3330, enters state MM IDLE, reset the location update attempt counter and sets the update status to U1 UPDATED. If the ROUTING AREA UPDATE ACCEPT message contains an IMSI, the mobile station is not allocated any TMSI, and shall delete any TMSI accordingly. If the ROUTING AREA UPDATE ACCEPT message contains a TMSI, the MS shall use this TMSI as new temporary identity. The MS shall delete its old TMSI and shall store the new TMSI. In this case, an ROUTING AREA UPDATE COMPLETE message is returned to the network. If neither a TMSI nor an IMSI has been included by the network in the ROUTING AREA UPDATE ACCEPT message, the old TMSI, if any is available, shall be kept. If the MS maintains a counter for "SIM/USIM considered invalid for non-GPRS services" events (see subclause 4.1.1.6A), then the MS shall reset this counter. If the MS is not configured for NAS signalling low priority, and any of the following conditions is fulfilled: - the MS initiated the combined routing area updating procedure due to a change of the registered location area; - the value of the Update type IE in the ROUTING AREA UPDATE REQUEST message indicated "combined RA/LA updating with IMSI attach"; or - the MS indicated support of EMM combined procedures in the MS network capability; then the MS may stop timer T3246 if running. Any timer used for triggering the location updating procedure (e.g. T3211, T3212) shall be stopped if running. The network receiving a ROUTING AREA UPDATE COMPLETE message stops timer T3350, changes to GMM-REGISTERED state NOTE: Upon receiving a ROUTING AREA UPDATE COMPLETE message, the SGSN sends a BSSAP+-TMSI-REALLOCATION-COMPLETE message as specified in 3GPP TS 29.018[ General Packet Radio Service (GPRS); Serving GPRS Support Node (SGSN) - Visitors Location Register (VLR); Gs interface layer 3 specification ]  [149]. 4.7.5.2.3.2 Combined routing area updating successful for GPRS services only Apart from the actions on the routing area updating attempt counter, the description for normal routing area update as specified in subclause 4.7.5.1.3 shall be followed. In addition, the following description for location area updating applies. The SGSN shall use GMM cause #28 "SMS provided via GPRS in this routing area" in the ROUTING AREA UPDATE ACCEPT message only if the MS requested "SMS-only service" by including the Additional update type IE in the ROUTING AREA UPDATE REQUEST message. The SGSN may indicate in the Update result IE in the ROUTING AREA UPDATE ACCEPT message that ISR is activated. The MS receiving the ROUTING AREA UPDATE ACCEPT message takes one of the following actions depending on the GMM cause: #2 (IMSI unknown in HLR); The MS shall stop timer T3330 if still running and shall reset the routing area updating attempt counter. The MS shall set the update status to U3 ROAMING NOT ALLOWED and shall delete any TMSI, LAI and ciphering key sequence number. The MS shall enter state GMM-REGISTERED.NORMAL-SERVICE. The new MM state is MM IDLE. The SIM/USIM shall be considered as invalid for non-GPRS services until switching off or the SIM/USIM is removed. If the message has been successfully integrity checked by the lower layers and the MS maintains a counter for "SIM/USIM considered invalid for non-GPRS services", then the MS shall set this counter to MS implementation-specific maximum value. #16 (MSC temporarily not reachable); or #17 (Network failure) The MS shall stop timer T3330 if still running, and shall enter state MM-IDLE. The routing area updating attempt counter shall be incremented. If the routing area updating attempt counter is less than 5, and the stored RAI is equal to the RAI of the current serving cell and the GMM update status is equal to GU1 UPDATED: - the MS shall keep the GMM update status GU1 UPDATED and changes state to GMM-REGISTERED.ATTEMPTING-TO-UPDATE-MM. The MS shall start timer T3311. When timer T3311 expires the combined routing area update procedure indicating "combined RA/LA updating with IMSI attach" is triggered again. If the routing area updating attempt counter is greater than or equal to 5: - the MS shall start timer T3302 and shall change to state GMM-REGISTERED.ATTEMPTING-TO-UPDATE-MM; - a GPRS MS operating in MS operation mode A shall then proceed with appropriate MM specific procedure; a GPRS MS operating in MS operation mode B may then proceed with appropriate MM specific procedures. The MM sublayer shall act as in network operation mode II as long as the combined GMM procedures are not successful and no new RA is entered. # 22 (Congestion); The MS shall change to state GMM-REGISTERED.ATTEMPTING-TO-UPDATE-MM, shall stop timer T3330 if still running, and shall enter state MM-IDLE. The MS shall set the routing area updating attempt counter to 5 and shall start timer T3302. # 28 (SMS provided via GPRS in this routing area); The MS shall stop timer T3330 if still running and shall reset the routing area updating attempt counter. The MS shall set the update status to U3 ROAMING NOT ALLOWED and shall delete any TMSI, LAI and ciphering key sequence number. The MS shall enter state GMM-REGISTERED.NORMAL-SERVICE. The new MM state is MM IDLE. The MS stays in the current serving cell and applies the normal cell reselection process. Other GMM causevalues and the case that no GMM cause IE was received are considered as abnormal cases. The combined routing area updating shall be considered as failed for non-GPRS services. The specification of the MS behaviour in those cases is specified in subclause 4.7.5.2.5.