CompTIA Security+ Question A-60

A new virtual server was created for the marketing department. The server was installed on an existing host machine. Users in the marketing department report that they are unable to connect to the server. Technicians verify that the server has an IP address in the same VLAN as the marketing department users. Which of the following is the MOST likely reason the users are unable to connect to the server?

A. The new virtual server’s MAC address was not added to the ACL on the switch
B. The new virtual server’s MAC address triggered a port security violation on the switch
C. The new virtual server’s MAC address triggered an implicit deny in the switch
D. The new virtual server’s MAC address was not added to the firewall rules on the switch

Answer: A

Explanation:
Configuring the switch to allow only traffic from computers based upon their physical address is known as MAC filtering. The physical address is known as the MAC address. Every network adapter has a unique MAC address hardcoded into the adapter. You can configure the ports of a switch to allow connections from computers with specific MAC addresses only and block all other MAC addresses. In computer networking, MAC Filtering (or GUI filtering, or layer 2 address filtering) refers to a security access control method whereby the 48-bit address assigned to each network card is used to determine access to the network. MAC addresses are uniquely assigned to each card, so using MAC filtering on a network permits and denies network access to specific devices through the use of blacklists and whitelists. While the restriction of network access through the use of lists is straightforward, an individual person is not identified by a MAC address, rather a device only, so an authorized person will need to have a whitelist entry for each device that he or she would use to access the network.