Cisco Certified Network Associate (CCNA) Practice Exam

How do you configure port security to allow a specific MAC address?

1. (config)#switchport port-security mac-address MAC ADDRESS

2. (config)#switchport port-security maximum NUMBER

3. (config)#switchport port-security enable

4. (config)#interface INTERFACE

The correct answer is: (config)#switchport port-security mac-address MAC ADDRESS

To configure port security to allow a specific MAC address, the command that needs to be used is indeed the one specifying the MAC address directly. When you enter the command to set a specific MAC address, you are defining which device is permitted to connect to that port based on its unique hardware address. This is crucial in a network for enhancing security as it helps prevent unauthorized devices from connecting. By using the appropriate command format that includes "switchport port-security mac-address MAC ADDRESS," you effectively tie the switch port's configuration to a particular MAC address. This means that only the device with this MAC address can transmit data over that port, and it reinforces network security by restricting access. Setting the maximum number of MAC addresses or enabling port security are important as well, but they address different aspects of port security. The maximum configuration specifies how many devices can be allowed at once, and enabling port security activates the feature on the switch port, but does not specify which MAC addresses are permitted. Thus, to specifically allow a certain MAC address, the direct assignment is required.