Question: When constructing BAP Control PDUs for flow control feedback at the IAB-MT (Integrated Access Backhaul - Mobile Terminal), what determines whether the feedback is constructed per BH RLC channel or per BAP routing ID?
Option 1: The configuration received from the Radio Resource Control (RRC) protocol.
Option 2: The type of Non-UP Traffic (e.g., signaling, data) indicated by the Non-UP Traffic Type IE in TS 38.473.
Option 3: The buffer load level that triggered the flow control feedback.
Option 4: The implementation choice of the IAB node itself, without external configuration.
Explanation: According to the specifications, the decision to construct a BAP Control PDU for flow control feedback per BH RLC channel or per BAP routing ID is based on the configuration received from the Radio Resource Control (RRC) protocol. This highlights the role of RRC in managing and configuring aspects of the radio access network, including backhaul adaptation protocols like BAP.