Question 1hardmultiple choice
Full question →hardmultiple choiceObjective-mapped
A security policy requires that only one management subnet be able to initiate SSH to a router. Which approach most directly supports that requirement?
Answer choices
Why each option matters
Good practice is not just finding the correct option. The wrong answers often show the exact trap the exam wants you to fall into.
A
Best answer
Use an ACL to permit SSH access only from the approved management subnet.
This is correct because the policy is specifically about restricting management access by source subnet.
B
Distractor review
Enable PortFast on the router interfaces.
This is wrong because PortFast is a switch feature, not a router management-access control.
C
Distractor review
Disable all logging on the router.
This is wrong because disabling logging weakens visibility and does not restrict management access.
D
Distractor review
Replace SSH with Telnet for easier filtering.
This is wrong because Telnet is less secure than SSH.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A frequent exam trap is assuming that enabling SSH alone fulfills the requirement to restrict management access to a single subnet. Candidates may overlook that SSH only encrypts the session but does not limit which source IP addresses can initiate connections. Without an ACL, any host can attempt SSH access, violating the security policy. Another trap is confusing unrelated features like PortFast or disabling logging as security controls, which do not restrict SSH access. Understanding that source-based filtering via ACLs is the direct method to enforce subnet restrictions is critical to avoid this mistake.
Technical deep dive
How to think about this question
Access Control Lists (ACLs) are fundamental security tools in Cisco networking that filter traffic based on defined criteria such as source IP addresses, destination IP addresses, and protocols. In the context of router management, ACLs can be applied to control which subnets or hosts are permitted to initiate management sessions like SSH. This selective filtering ensures that only authorized management subnets can access the router’s command-line interface, enhancing security by limiting exposure to trusted sources. When a security policy mandates that only one management subnet can initiate SSH sessions, the network administrator must configure an ACL that explicitly permits SSH traffic (TCP port 22) from that approved subnet while denying all other sources. This ACL is then applied inbound on the router’s interface that receives management traffic. The router continues to run SSH as the secure management protocol, but the ACL enforces the source-based restriction, effectively combining protocol security with access control. A common exam trap is confusing protocol security with access control. While SSH encrypts management sessions, it does not restrict which hosts can connect. Some candidates mistakenly believe enabling SSH alone satisfies the policy. However, without an ACL restricting source IPs, any host can attempt SSH connections. Practically, combining SSH with ACLs is standard practice to both secure and limit management access, reflecting real-world Cisco network security design.
KKey Concepts to Remember
- An Access Control List (ACL) filters traffic by source IP, destination IP, and protocol to enforce security policies on Cisco routers.
- Applying an ACL inbound on a router interface restricts which source subnets can initiate management protocols like SSH.
- SSH encrypts management sessions but does not inherently restrict which hosts can initiate connections to the router.
- Combining SSH with ACLs provides both secure communication and controlled access from trusted management subnets.
- PortFast is a switch feature that affects Spanning Tree Protocol convergence and does not control router management access.
- Disabling logging reduces visibility into network events and does not restrict or enhance management access security.
- Replacing SSH with Telnet reduces security because Telnet transmits data in clear text and does not support source filtering inherently.
- Security policies requiring subnet-based restrictions on management access are best implemented using ACLs to permit only approved sources.
TExam Day Tips
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
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More questions from this exam
Keep practising from the same exam bank, or move into a focused topic page if this question exposed a weak area.
Question 1
A router learns the same prefix from both OSPF and EIGRP. Which route is installed by default?
Question 2
A router shows this output: R1#show ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface 10.1.1.2 1 FULL/DR 00:00:34 192.168.12.2 GigabitEthernet0/0 10.1.1.3 1 2WAY/DROTHER 00:00:39 192.168.12.3 GigabitEthernet0/0 Which statement is correct?
Question 3
What is the OSPF metric called?
Question 4
A non-root switch has two uplinks toward the root bridge. One path has a lower total STP cost than the other. What role will the lower-cost uplink have?
Question 5
A router interface applies this ACL inbound: 10 deny tcp any any eq 80 20 permit ip any any A user reports that web browsing to a server by IP address fails, but ping works. Which statement best explains the behavior?
Question 6
A router learns route 198.51.100.0/24 from OSPF with AD 110 and also has a static route to the same prefix configured with AD 150. Which route is installed?
FAQ
Questions learners often ask
What does this 200-301 question test?
An Access Control List (ACL) filters traffic by source IP, destination IP, and protocol to enforce security policies on Cisco routers.
What is the correct answer to this question?
The correct answer is: Use an ACL to permit SSH access only from the approved management subnet. — The most direct approach is to use an ACL that restricts which source subnet is permitted to reach SSH management access on the router. In practical terms, SSH can remain enabled as the secure protocol, but access to it should still be limited to trusted management sources. That is a classic example of combining secure protocol choice with source restriction. This is stronger than enabling SSH alone, because SSH secures the session, but source filtering limits who is even allowed to try.
What should I do if I get this 200-301 question wrong?
Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.
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