In this substate, the UE has no dedicated channel allocated.
Instead the UE uses the common channels, the RACH and FACH to communicate, both for signaling messages and small amounts of data (best effort), with the network. A dedicated control channel (DCCH) or common control channel (CCCH) is used for control signaling.
A dedicated traffic channel is used for user data transmission. CCCH, DCCH and DTCH are mapped onto a common transport channel (RACH and FACH).
The UE performs cell reselections and sends periodically Cell Update messages to RNC and is therefore known on cell level in the RNC. In this state the UE is also capable of listening to the broadcast channel (mapped on FACH) to require system information.
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