Quick Answer
The answer is BPDU Guard and Port Security, as these two features directly strengthen access-switch security for user-facing ports. Port Security works by limiting the number of learned MAC addresses on a port, preventing MAC flooding attacks and unauthorized device connections, while BPDU Guard immediately err-disables a port configured as an edge port if it unexpectedly receives a Bridge Protocol Data Unit, protecting against rogue switch or bridge loops. On the CCNA 200-301 v2 exam, this pairing tests your understanding of foundational Layer 2 hardening—Port Security controls who connects, and BPDU Guard ensures no accidental or malicious STP manipulation occurs. A common trap is assuming BPDU Guard prevents all BPDUs; it only reacts to unexpected ones on ports explicitly set as edge ports via spanning-tree portfast. Remember the mnemonic: “Ports police MACs, BPDU Guard attacks the stack.”
This 200-301 practice question tests your understanding of network services and security. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. A key principle to apply: port security limits the number of MAC addresses learned on a switch port to prevent unauthorized device access and MAC flooding attacks.. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
Which two features commonly strengthen access-switch security for user-facing ports? (Choose two.)
Port security
Correct. It helps control which MAC addresses may appear on a port.
BPDU Guard
Correct. It protects PortFast edge ports from unexpected switch connections.
Administrative distance
Why wrong: Administrative distance is a routing preference, not an access-switch security feature.
Route summarization
Why wrong: Route summarization is unrelated to access-port hardening.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
Port security
Port security can limit learned MAC addresses, and BPDU Guard can shut down an edge port that unexpectedly receives BPDUs.
Key principle: Port security limits the number of MAC addresses learned on a switch port to prevent unauthorized device access and MAC flooding attacks.
Answer analysis
For each option: why learners choose it and why it is or isn't the right answer here.
Port security
Why this is correct
Correct. It helps control which MAC addresses may appear on a port.
Related concept
Port security limits the number of MAC addresses learned on a switch port to prevent unauthorized device access and MAC flooding attacks.
BPDU Guard
Why this is correct
Correct. It protects PortFast edge ports from unexpected switch connections.
Related concept
Port security limits the number of MAC addresses learned on a switch port to prevent unauthorized device access and MAC flooding attacks.
Administrative distance
Why it's wrong here
Administrative distance is a routing preference, not an access-switch security feature.
When this WOULD be correct
If the question were about routing protocols and their configurations, asking which feature affects the selection of routes, administrative distance would be the correct answer as it helps routers choose the best path based on the trust level of the routing information.
Route summarization
Why it's wrong here
Route summarization is unrelated to access-port hardening.
When this WOULD be correct
In a question focused on optimizing routing protocols and reducing routing table size, such as 'What technique can be used to minimize routing updates in a large network?', route summarization would be the correct answer as it effectively summarizes multiple routes into a single advertisement.
Option-by-option analysis
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.
Why this is correct
Correct. It helps control which MAC addresses may appear on a port.
Why this is wrong here
Administrative distance is a metric used to determine the trustworthiness of routing information from different sources, not a feature that directly enhances access-switch security for user-facing ports.
★ When this WOULD be the correct answer
If the question were about routing protocols and their configurations, asking which feature affects the selection of routes, administrative distance would be the correct answer as it helps routers choose the best path based on the trust level of the routing information.
Why candidates choose this
Candidates may confuse administrative distance with security measures, thinking that it relates to controlling access or managing user connections, leading them to mistakenly select it as a security feature.
Why this is wrong here
Route summarization is a technique used to reduce the number of routes in a routing table, which is not directly related to securing user-facing ports on access switches. It does not enhance the security of access-switch ports where users connect their devices.
★ When this WOULD be the correct answer
In a question focused on optimizing routing protocols and reducing routing table size, such as 'What technique can be used to minimize routing updates in a large network?', route summarization would be the correct answer as it effectively summarizes multiple routes into a single advertisement.
Why candidates choose this
Candidates may confuse route summarization with network security concepts, thinking that reducing routing information could somehow relate to securing access ports, especially if they have limited understanding of specific switch security features.
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?”
Common exam traps
A common exam trap is selecting administrative distance or route summarization as security features for user-facing access ports. Administrative distance is a routing protocol metric used to select the best path and has no role in access-switch port security. Similarly, route summarization is a routing optimization technique that reduces routing table size but does not affect port security. Candidates may confuse these routing concepts with security features due to their importance in network design, but they do not strengthen access-switch security for user-facing ports. Recognizing this distinction is critical to avoid losing points on this question.
Detailed technical explanation
Access-switch security focuses on protecting user-facing ports from unauthorized or malicious devices connecting to the network. Port security is a key feature that allows the switch to limit the number of MAC addresses learned on a port, effectively controlling which devices can send traffic through that port. This prevents MAC flooding attacks and unauthorized device access by restricting port access to known MAC addresses. BPDU Guard is another critical security feature for access ports configured with PortFast. It protects the network by shutting down a port if Bridge Protocol Data Units (BPDUs) are received on that port, which indicates an unexpected switch connection. This prevents potential Layer 2 loops caused by unauthorized switches connecting to edge ports. A common exam trap is confusing administrative distance and route summarization with access-port security features. Administrative distance is a routing protocol preference metric and does not apply to port security. Route summarization optimizes routing tables but does not enhance access port security. Understanding these distinctions helps avoid selecting incorrect options that are unrelated to switch port security hardening.
Key takeaway
Port security limits the number of MAC addresses learned on a switch port to prevent unauthorized device access and MAC flooding attacks.
Real-world example
A practitioner preparing for the 200-301 exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Port security limits the number of MAC addresses learned on a switch port to prevent unauthorized device access and MAC flooding attacks. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
What to study next
Review port security limits the number of MAC addresses learned on a switch port to prevent unauthorized device access and MAC flooding attacks., then practise related 200-301 questions on the same topic to reinforce the concept.
Network Services and Security — study guide chapter
Learn the concepts, then practise the questions
Network Services and Security practice questions
Targeted practice on this topic area only
All 200-301 questions
1,819 questions across all exam domains
CCNA 200-301 v2 study guide
Full concept coverage aligned to exam objectives
200-301 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Practise 200-301 questions linked to Network Infrastructure and Connectivity.
Practise 200-301 questions linked to Switching and Network Access.
Practise 200-301 questions linked to IP Routing.
Practise 200-301 questions linked to Network Services and Security.
Practise 200-301 questions linked to AI and Network Operations.
Practise IPv4 subnetting, CIDR, masks, host ranges and subnet selection.
Practise OSPF neighbours, router IDs, metrics, areas and routing-table interpretation.
Practise VLANs, access ports, trunks, allowed VLANs and switching scenarios.
Practise spanning tree, root bridge election, port roles and STP troubleshooting.
Practise LACP, PAgP, port-channel behaviour and bundle requirements.
Practise standard and extended ACLs, permit/deny logic and traffic filtering.
Practise static NAT, dynamic NAT, PAT and inside/outside address translation.
Practice this exam
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Network Services and Security — This question tests Network Services and Security — Port security limits the number of MAC addresses learned on a switch port to prevent unauthorized device access and MAC flooding attacks..
The correct answer is: Port security — Port security can limit learned MAC addresses, and BPDU Guard can shut down an edge port that unexpectedly receives BPDUs.
Review port security limits the number of MAC addresses learned on a switch port to prevent unauthorized device access and MAC flooding attacks., then practise related 200-301 questions on the same topic to reinforce the concept.
Port security limits the number of MAC addresses learned on a switch port to prevent unauthorized device access and MAC flooding attacks.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Same concept, more angles
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. On a user access port, port security is configured with a maximum of 2 MAC addresses and violation mode restrict. A third unauthorized device is connected through a small unmanaged switch. What happens?
mediumWhy B: In restrict mode, frames from unknown MAC addresses are dropped, the violation counter increments, and logging or SNMP traps can be generated. Unlike shutdown mode, the interface does not go err-disabled.
Variation 2. An access switch port shuts down as soon as a user connects a small unmanaged switch under the desk. Which feature caused that behavior?
mediumWhy B: BPDU Guard is meant to protect access ports by shutting them down if BPDUs are received. That usually means someone connected another switch where only an endpoint should exist.
Keep practising
Last reviewed: May 17, 2026
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.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.