What is the physical address used to identify a node on a network called?

The physical address used to identify a node on a network is known as a MAC address (Media Access Control address). This unique identifier is assigned to a network interface card (NIC) and operates at the data link layer of the OSI model. Each MAC address is assigned by the manufacturer, ensuring that no two devices on the same local network have the same address.

This uniqueness is essential for ensuring that data packets sent over a local network are delivered accurately to the correct device. When frames are sent over Ethernet or Wi-Fi networks, they use the MAC address to identify both the sender and the recipient, facilitating precise communication between devices.

In contrast, an IP address is dynamic and can change as devices connect to different networks; it functions at the network layer, enabling communication over the Internet or larger networks. Network address is a broader term that can refer to both MAC addresses and IP addresses, while host address typically pertains to the IP address of a device on a network. Therefore, the MAC address is the specific physical address that uniquely identifies network nodes at the hardware level.