What is the term for the unique identifier assigned to network interfaces for communications at the data link layer?

What is the term for the unique identifier assigned to network interfaces for communications at the data link layer?

• A. IP address
• B. Ports
• C. MAC address
• D. Band options

Answer: (C)

In the data link layer, devices on a local network are identified by MAC addresses—the unique hardware identifiers assigned to network interfaces. A MAC address is typically 48 bits long and written as six hexadecimal octets (for example, 01:23:45:67:89:AB). This address is usually burned into the NIC by the manufacturer and is used by switches to deliver frames to the correct device on the same local segment by learning which port is associated with which MAC. Unlike IP addresses, MAC addresses aren’t routable across networks; they exist for local delivery. Port numbers pertain to the transport layer, not the data link layer, and “band options” isn’t a standard networking term. So, the term for the unique identifier assigned to network interfaces for communications at the data link layer is the MAC address.

In the data link layer, devices on a local network are identified by MAC addresses—the unique hardware identifiers assigned to network interfaces. A MAC address is typically 48 bits long and written as six hexadecimal octets (for example, 01:23:45:67:89:AB). This address is usually burned into the NIC by the manufacturer and is used by switches to deliver frames to the correct device on the same local segment by learning which port is associated with which MAC. Unlike IP addresses, MAC addresses aren’t routable across networks; they exist for local delivery. Port numbers pertain to the transport layer, not the data link layer, and “band options” isn’t a standard networking term. So, the term for the unique identifier assigned to network interfaces for communications at the data link layer is the MAC address.