CCNA Switching and Network Access Practice Question
Which spanning-tree port state listens for BPDUs and participates in STP, but does not learn MAC addresses yet?
⚠ Common exam trap
Be careful not to confuse the listening state with learning, as both involve BPDU processing but differ in MAC address table updates.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Listening
In the classic 802.1D sequence, the listening state processes BPDUs and prepares for forwarding decisions, but it does not populate the MAC address table yet.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Blocking
Why it's wrong here
In the Blocking state, a port does receive BPDUs to monitor the topology, but it does not actively listen as part of the transition to forwarding; it remains in a passive condition until the STP algorithm determines it should move. The question asks for the state that listens for BPDUs and then proceeds to the next step, which is the Listening state itself, not Blocking. Blocking is a non-forwarding state that does not prepare the port to learn MAC addresses or forward frames, so it is not the correct answer.
When this WOULD be correct
If the question asked which port state does not forward frames and only listens for BPDUs without participating in STP, then Blocking would be the correct answer. This would imply a focus on the prevention of loops rather than active participation.
- ✓
Listening
Why this is correct
The Listening state follows the Blocking state and precedes the Learning state in STP convergence. During Listening, the port actively listens for BPDUs to determine the root bridge and its port role, and it does not learn MAC addresses or forward user traffic. This is the state that matches the question's description, as it is the phase specifically designated for BPDU listening to build the STP topology.
- ✗
Learning
Why it's wrong here
The Learning state is part of the STP convergence sequence but occurs after Listening. Its primary job is to populate the MAC address table by examining source addresses of received frames, and it does not listen for BPDUs to make topology decisions. Since the question asks which state specifically listens for BPDUs to prepare for forwarding, Learning is the wrong choice because it is a later stage focused on MAC learning, not BPDU listening.
When this WOULD be correct
If the question asked about a state that both listens for BPDUs and learns MAC addresses, such as during the transition from Listening to Forwarding, then 'Learning' would be the correct answer.
- ✗
Forwarding
Why it's wrong here
The Forwarding state is the operational mode where a port sends and receives user data frames, and it also continues to receive BPDUs for ongoing BPDU processing. However, its defining function is frame forwarding, not the active listening for BPDUs that occurs during the initial convergence process. The state that is specifically characterized by listening for BPDUs before any data transmission is the Listening state, so Forwarding does not match the description.
When this WOULD be correct
If the question asked for the state that both listens for BPDUs and actively forwards data frames while learning MAC addresses, 'Forwarding' would be the correct answer, as it describes the port state that fully participates in STP and data transmission.
Option-by-option analysis
Why each answer is right or wrong
Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The 200-301 exam frequently reuses these exact scenarios with slightly different constraints.
✓ListeningCorrect answer▾
Why this is correct
The Listening state follows the Blocking state and precedes the Learning state in STP convergence. During Listening, the port actively listens for BPDUs to determine the root bridge and its port role, and it does not learn MAC addresses or forward user traffic. This is the state that matches the question's description, as it is the phase specifically designated for BPDU listening to build the STP topology.
✗BlockingWrong answer — click to see why▾
Why this is wrong here
In the blocking state, the port does not participate in STP actively; it only receives BPDUs but does not send them or transition toward forwarding. The question specifies a state that listens for BPDUs and participates in STP, which is the listening state, not blocking.
★ When this WOULD be the correct answer
If the question asked which port state does not forward frames and only listens for BPDUs without participating in STP, then Blocking would be the correct answer. This would imply a focus on the prevention of loops rather than active participation.
Why candidates choose this
Students often confuse blocking with listening because both states do not forward traffic and both receive BPDUs. However, blocking is the initial state after a port is enabled, and it does not actively participate in STP decision-making like listening does.
✗LearningWrong answer — click to see why▾
Why this is wrong here
The learning state populates the MAC address table by learning source MAC addresses from incoming frames, which directly contradicts the question's requirement that the state does not learn MAC addresses. Learning occurs after listening and before forwarding.
★ When this WOULD be the correct answer
If the question asked about a state that both listens for BPDUs and learns MAC addresses, such as during the transition from Listening to Forwarding, then 'Learning' would be the correct answer.
Why candidates choose this
Students may think that learning is the state where the port learns about the network topology via BPDUs, but in STP, learning specifically refers to MAC address learning, not BPDU processing. The listening state is where BPDU processing and STP participation occur without MAC learning.
✗ForwardingWrong answer — click to see why▾
Why this is wrong here
The forwarding state both learns MAC addresses and forwards traffic, which violates the condition that the state does not learn MAC addresses. Forwarding is the final state where the port is fully operational.
★ When this WOULD be the correct answer
If the question asked for the state that both listens for BPDUs and actively forwards data frames while learning MAC addresses, 'Forwarding' would be the correct answer, as it describes the port state that fully participates in STP and data transmission.
Why candidates choose this
Some students might assume that forwarding includes only traffic forwarding and not MAC learning, but in STP, the forwarding state also includes learning MAC addresses from incoming frames. The listening state is the only state that participates in STP without learning MAC addresses.
Analysis generated from the official 200-301blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Visual reference
Quick reference
IPv4 Address Class Summary
| Class | First Octet Range | Default Mask | Networks | Hosts per Network |
|---|---|---|---|---|
| A | 1–126 | /8 (255.0.0.0) | 126 | 16,777,214 |
| B | 128–191 | /16 (255.255.0.0) | 16,384 | 65,534 |
| C | 192–223 | /24 (255.255.255.0) | 2,097,152 | 254 |
| D | 224–239 | N/A | Multicast groups | — |
| E | 240–255 | N/A | Reserved / experimental | — |
127.x.x.x is reserved for loopback. Modern networks use CIDR (classless) rather than classful addressing.
Go deeper
Related to this question
Learn chapter
Interpreting Packet Capture Output for Layer 2/3 Troubleshooting
Key term
STP
STP (Spanning Tree Protocol) is a network protocol that prevents loops in Ethernet networks by creating a loop-free logical topology.
Key term
MAC address
A MAC address is a unique hardware identifier assigned to a network interface card that allows devices to communicate on a local network.
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Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This 200-301 practice question is part of Courseiva's free Cisco certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 200-301 exam.