RRC operation modes?

What are the RRC operation modes?

There are two types of Mode 

1. Idle mode 

2. Connected mode.

There are 4 RRC States: Cell_DCH, Cell_FACH, URA_PCH and Cell_PCH.

Idle Mode: In idle mode, after the UE is switch ON and UE is able to receive system information message from cell.

CELL_DCH: In this state dedicated physical channel is allocated to the UE in UL and DL active set level

CELL_FACH: No dedicated channel is allocated to UE, But RACH and FACH cannel can be used, both transferring signaling message and small amount of data. And in this state UE perform cell re-selection and after a reselection always send a cell update message to RNC

CELL_PCH: In this state UE perform to monitoring of paging information

URA_PCH: It is similar to CELL_PCH expected that the UE does not execute cell update after each re-selection, but instead read URA (UTRA registration area) identities from the broadcast channel.