When a Universal Terrestrial Radio Access Network (UTRAN) receives an
indication on Layer 3 (L3) (an L1/L2 indication is also possible) from
the User Equipment (UE) that it is switching the High Speed-Data Shared
Channel (HS-DSCH) reception to another cell in the active set (AS), the
UTRAN sends a reconfiguration message to the UE via the target cell using
a pre-configured configuration that UE has taken into use. The message
can only include an indication that the pre-defined configuration can be
used further by the UE or that a complete new configuration is to be
used, e.g., using new HARQ info or even a hard handover (HHO) to another
frequency. After receiving the configuration message, the UE responds
with a normal reconfiguration complete message.