IDLE to CM-CONNECTED, and from CM-CONNECTED to CM-IDLE. The UE NAS layer identi- fies a selected PLMN and equivalent PLMNs. Cell selection is always based on CD-SSBs located on the synchronization raster. The UE scans the NR frequency bands and for each car- rier frequency identifies the strongest cell and the associated CD-SSB. It then detects broad- cast SI of the cell to identify its PLMN(s). The UE may scan each carrier in certain order during initial cell selection or take advantage of stored information to expedite the search dur- ing stored information cell selection. The UE then tries to identify a suitable cell. If it is not able to identify a suitable cell, it then tries to identify an acceptable cell. When a suitable cell or an acceptable cell is found, the UE camps on it and begins the cell reselection procedure. A suitable cell is a cell whose measured cell attributes satisfy the cell selection criteria; the cell PLMN is the selected PLMN, registered or an equivalent PLMN; the cell is not barred or 266 Chapter 2 reserved, and the cell is not part of a tracking area which is in the list of forbidden tracking areas for roaming. An acceptable cell is a cell whose measured cell attributes satisfy the cell selection criteria, and the cell is not barred. Upon transition from RRC_CONNECTED or RRC_INACTIVE to RRC_IDLE state, a UE may camp on a cell as a result of cell selection according to the frequency assigned to the UE via RRC signaling in the state transition message. The UE may attempt to find a suitable cell in the above manner described for stored information or initial cell selection. If no suitable cell is found on any frequency or RAT, the UE may attempt to find an acceptable cell. In multi-beam operations, the cell quality is derived among the beams that are correspond- ing to the same cell [8]. The cell selection criterion S is considered fulfilled, if the following criteria are satisfied: Srxlev > 0 AND Squal > 0 where Srxlev = Qrxlevmeas - (Qrxlevmin + Qrxlevminoffset) - P compensation Qoffset