For the purposes of the present document, the terms and definitions given in TR 21.905
, TS 23.167
and the following apply. A term defined in the present document takes precedence over the definition of the same term, if any, in TR 21.905
or TS 23.167
Limited Service Mode:
The UE state that only allows emergency calls. This state is entered when a UE is unable to find a suitable cell to camp on, or the SIM is not inserted, or if it receives certain responses to a Location Registration request (e.g., "illegal UE"), it attempts to camp on a cell irrespective of the PLMN identity. See TS 23.122
A UE that does not have a UICC or a UE with an IMSI that does not have corresponding subscription information in the HLR.
Local regulation categories:
Normal Mode: Only subscribers are supported. Meaning, an emergency call is treated by the network as any other call regarding subscription. The UE must be authenticated and authorized for service in their current location in order to gain network access for emergency calling.
Valid IMSI limited: Only subscribers with a valid IMSI that can be authenticated are supported by the network. They may not be authorized for PS service in their current location but are allowed to over ride subscription restrictions to initiate an IMS emergency call.
All Emergency Calls (All-EmCalls): Regulation requires all UEs to be able to access the network to initiate an emergency call, regardless of authentication or authorization status. Therefore, even a UE without valid credentials should be served (e.g. UE's without an UICC, UE's that received "IMSI unknown in HLR" or "PLMN not allowed" rejects).
For the purposes of the present document, the abbreviations given in TR 21.905
and the following apply. An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in TR 21.905