What does a MAC address do?

A MAC (Media Access Control) address plays a crucial role in networking by uniquely identifying each node on a local network. It is a hardware address that is embedded into the network interface card (NIC) of a device, such as a computer or a router. Unlike IP addresses that can change depending on the network configuration, MAC addresses remain constant and serve as a permanent identifier for devices on the same local area network (LAN).

The uniqueness of the MAC address is what allows network devices to communicate with one another properly. When data packets are transmitted over the network, the MAC address is used to ensure that the information reaches the correct device. This ability to uniquely identify devices is essential for managing network traffic and maintaining efficient communication between devices.

In contrast, the other options provided are functionalities that are not associated with MAC addresses:

• Identifying online services pertains to service discovery on the internet and is not related to MAC addresses.

• Routing packets across the internet is performed by routers using IP addresses, not MAC addresses.

• Resolving hostnames to IP addresses is the function of DNS (Domain Name System), separating it further from the role of a MAC address.

Overall, a MAC address is fundamental for networking, acting as a unique identifier for devices, enabling successful