Question: Under what condition is the Radio Link Parameter Update procedure **not** initiated by Node B in UTRAN's Iub interface (NBAP signalling)?
Option 1: When HS-DSCH related radio link parameter values need to be updated on the RNC side.
Option 2: If a Prepared Reconfiguration already exists, as defined in system configuration protocols.
Option 3: When E-DCH or UL CLTD related parameters require updating on Node B.
Option 4: During initial setup of the Node B and RNC communication link.
Explanation: The correct answer is Option 2 because, according to the specifications, the Radio Link Parameter Update procedure shall not be initiated if a Prepared Reconfiguration exists. This condition highlights an important nuance in the management of radio link parameters between Node B and RNC, ensuring that updates are coordinated properly to avoid conflicts with pending reconfigurations.