On a switched network where STP is enabled on all devices, when a downstream device detects a topology change, it continuously sends configuration BPDUs to the upstream device until the root bridge is informed of the topology change.

The statement is incorrect. When a downstream device on an STP-enabled network detects a topology change, it does not send configuration BPDUs. Instead, it sends a special type of BPDU called a Topology Change Notification (TCN) BPDU out of its root port. This TCN BPDU is sent repeatedly until the upstream switch acknowledges it by setting the Topology Change Acknowledgment (TCA) bit in its next configuration BPDU. The process is designed to inform the root bridge of the change, which then instructs all switches to shorten their MAC address aging time.

The statement is presented as a factual claim. It is false because the type of BPDU sent by the downstream device to signal a topology change is a TCN BPDU, not a standard configuration BPDU.

1. Huawei HCIA-Datacom V1.0 Training Material, "STP Topology Change," Section: STP Other Concepts. This section details the TCN process, specifying that TCN BPDUs, not configuration BPDUs, are sent upstream to notify the network of a topology change.

2. IEEE Std 802.1D-2004, "IEEE Standard for Local and metropolitan area networks--Media Access Control (MAC) Bridges," Clause 17.5, "Topology change." This standard defines the protocol behavior, stating that a bridge detecting a topology change shall transmit TCN messages on its root port.