Question: In the context of flow control over the Gb Interface for General Packet Radio Service (GPRS), what is a key characteristic of how the downlink flow control mechanism operates in relation to queue management?
Option 1: Dynamic adjustment of uplink buffer sizes based on real-time network congestion.
Option 2: Implementation-dependent scheduling algorithm in the BSS for all MSs per BVCI.
Option 3: SGSN passes LLC PDUs to BSS via BSSGP until allowed BSSGP throughput (per BVCI, optionally per MS or PFC) is reached.
Option 4: Automatic redirection of downlink traffic to alternate cells in case of high load.
Explanation: This option accurately reflects a core principle of the downlink flow control mechanism. The SGSN continues to forward LLC PDUs to the BSS via BSSGP until the predefined allowed BSSGP throughput (which can be set per BVCI, and optionally more granularly per MS or per Packet Flow Context) is met, ensuring controlled loading of BSS LLC PDU queues.