Section: 4.1.2.1.2 Substates of the MM IDLE state
Content: For the description of the behaviour of the MS the MM IDLE state is subdivided in several substates, also called the service states. The service state pertains to the whole MS (ME alone if no SIM/USIM is inserted, or ME plus SIM/USIM). The service state depends on the update status (see subclause 4.1.2.2) and on the selected cell. 19.1 NORMAL SERVICE Valid subscriber data are available, update status is U1, a cell is selected that belongs to the LA where the subscriber is registered. In this state, all requests from the CM layers are treated normally. 19.2 ATTEMPTING TO UPDATE Valid subscriber data are available, update status is U2 and a cell is selected. Requests from upper layers are accepted. Emergency call requests are treated normally, otherwise the request triggers first a location updating attempt in the selected cell, and then triggers the needed procedure only in case of successful location updating, otherwise the request is rejected. 19.3 LIMITED SERVICE Valid subscriber data are available, update status is U3, and a cell is selected, which is known not to be able to provide normal service. Only emergency services are offered. 19.4 NO IMSI No valid subscriber data (no SIM/USIM, or the SIM/USIM is not considered valid by the ME), and a cell is selected. Only emergency services are offered. 19.5 NO CELL AVAILABLE No cell can be selected. This state is entered after a first intensive search failed (state 19.7). Cells are searched at a low rhythm. This state is also entered when S1 mode is activated in the MS and current cell is an E-UTRAN cell. No services, except those provided by CS fallback and SMS over SGs, are offered. 19.6 LOCATION UPDATE NEEDED Valid subscriber data are available, and for some reason a location updating must be done as soon as possible (for instance update status is U1 but the selected cell is not in the registered LA, or the timer has expired). This state is usually of no duration, but can last, e.g. due to access class control, (see subclause 4.1.1.2.1). 19.7 PLMN SEARCH The mobile station is searching for PLMNs, and the conditions for state 19.8 are not met. This state is ended when either a cell is selected (the new state is 19.1, 19.3 or 19.6), or when it is concluded that no cell is available for the moment (the new state is 19.5). 19.8 PLMN SEARCH, NORMAL SERVICE Valid subscriber data are available, update status is U1, a cell is selected which belongs to the LA where the subscriber is registered, and the mobile station is searching for PLMNs. This state is ended when either a cell is selected (the new state is 19.1, 19.3 or 19.6), or when it is concluded that no cell is available for the moment (the new state is 19.5). 19.9 RECEIVING GROUP CALL (NORMAL SERVICE) Only applicable for mobile stations supporting VGCS listening or VBS listening. Valid subscriber data are available, update status is U1, a VGCS channel or VBS channel is received in a cell that belongs to the LA where the subscriber is registered. In this state, only requests from the GCC or BCC layers are treated. 19.10 RECEIVING GROUP CALL (LIMITED SERVICE) Only applicable for mobile stations supporting VGCS listening or VBS listening. Valid subscriber data are available, update status is U3, a VGCS channel or VBS channel is received in a cell which is known not to be able to provide normal service. In this state, only requests from the GCC or BCC layers for the reception of VGCS or VBS calls are treated and group call emergency services are offered. 19.11 eCALL INACTIVE Valid subscriber data are available, update status is U4, and a cell is selected, which is expected to be able to provide normal service. Only emergency services and test/reconfiguration calls (see 3GPP TS 22.101[ Service aspects; Service principles ]  [8]) can be initiated by the mobile station. This state is applicable only to an eCall only mobile station (as determined by information configured in USIM). The state is entered by the mobile station in order to avoid MM activity and MM signalling in the absence of an emergency call or test/reconfiguration call. The state is ended when an emergency services or test/reconfiguration calls[8] is initiated by the mobile station, the new state depends on the result of the procedure when returning to MM-IDLE described in subclause 4.2.3.