This TS specifies the Access Stratum (AS) part of the Idle Mode procedures applicable to a UE. The nonaccess stratum (NAS) part of Idle mode procedures and processes is specified in TS 23.122
This TS also specifies cell selection and reselection processes applicable to UEs in connected mode. Invocation of these processes is described in TS 25.331
This TS specifies the model for the functional division between the NAS and AS in a UE.
This TS applies to all UEs that support at least UTRA, including multi-RAT UEs as described in 3GPP specifications, in the following cases:
When the UE is camped on a UTRA cell;
When the UE is searching for a cell to camp on;
NOTE: The details for those cases are described in the specifications of the other RAT.
This TS presents also examples of inter-layer procedures related to the idle mode processes and describes idle mode functionality of a multi-RAT UTRA/GSM/E-UTRA UE.
This TS also specifies how idle-mode and reselection procedures are affected by the provision of MBMS services.