Section: 4.3.1.5 Abnormal cases on the network side
Content: The following abnormal cases can be identified: a) RR connection failure: If the RR connection is lost before the TMSI REALLOCATION COMPLETE message is received, the network shall release all MM connections, if any. Furthermore, the network should consider both the old and the new TMSI as occupied for a certain recovery time. During this period the network: - may use the IMSI for paging or network originated transactions on the CM layer. Upon response from the mobile station the TMSI reallocation procedure shall be restarted; - may consider the new TMSI as valid if it is used by the mobile station; or - may use the identification procedure followed by a new TMSI reallocation procedure, if the mobile station uses the old TMSI (see subclause 4.3.3). Other implementations are possible, e.g. the network may page with the old TMSI. b) Expiry of timer T3250: The TMSI reallocation procedure is supervised by the timer T3250 (see example in figure 4.1). At expiry of timer T3250 the network may release the RR connection. In this case, the network shall abort the reallocation procedure release all MM connections if any, and follow the rules for the case a as described above. Figure 4.1/3GPP TS 24.008[ Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 ] : TMSI reallocation sequence