Huawei Certified Network Associate – Routing and Switching (HCNA-RS, legacy) — Question 29

Which of the following statements are true about STP BPDUs?

Answer options

• A. During initialization, each switch enabled with STP proactively sends configuration BPDUs.
• B. BPDUs are encapsulated in Ethernet frames and the destination MAC address is a multicast MAC address.
• C. After STP is enabled on a port, the switch periodically sends TCN BPDUs through the designated port.
• D. STP has two types of packets: configuration BPDU and TCN BPDU.

Correct answer: D

Explanation

The correct answer is D because STP indeed has two types of BPDUs: configuration BPDUs and TCN BPDUs, which are essential for maintaining the spanning tree. Option A is misleading as BPDUs are sent periodically rather than proactively during initialization. Option B is incorrect in its implication about the nature of the MAC address used, while option C misrepresents the function of TCN BPDUs, which are not sent periodically through the designated port after STP is enabled.