Cisco Certified Network Associate (CCNA) Practice Exam

What are best practices when disabling unused services on Cisco devices?

1. Enable Cisco Discovery Protocol on all interfaces

2. Leave all ports active for easy troubleshooting

3. Disable all unnecessary services and protocols

4. Limit access to only specific user credentials

The correct answer is: Disable all unnecessary services and protocols

Disabling unnecessary services and protocols on Cisco devices is a fundamental security measure that minimizes the attack surface of those devices. This practice helps to protect against vulnerabilities that could be exploited if those services were left active. By turning off services that are not in use, network administrators reduce the number of potential entry points for an attacker, subsequently enhancing the overall security posture of the network. Furthermore, this can improve the performance and stability of network devices, as each active service consumes resources. Enabling Cisco Discovery Protocol on all interfaces or leaving all ports active could expose the device to unnecessary risks and complicate the network environment, while limiting access to only specific user credentials, while important for securing user access, does not directly relate to the disabling of unused services. Hence, disabling all unnecessary services and protocols is recognized as a best practice.