A wireless device first successfully completes an Inter-RAT procedure, which is either an Inter-RAT handover, Inter-RAT cell reselection or Inter-RAT cell change order from UTRAN procedure. The wireless device then determines if a USIM is present. If the USIM is present, the wireless device determines if a new security key set was received and unused for ciphering and integrity functions during a current RRC connection. If a new key set was present and unused, the wireless device stores a value of zero into the USIM as a security START value for the CN domain associated with the RRC connection.