What does the MAC address in an Ethernet frame represent?

The MAC address in an Ethernet frame represents the physical address of a device on the network. Each network interface controller (NIC) is assigned a unique MAC address, which serves as a hardware identifier for that specific device. This address facilitates the communication between devices on the same local area network (LAN) by allowing them to identify each other at the data link layer of the OSI model.

When a device sends a frame over Ethernet, it includes the destination MAC address in the header of that frame. This enables switches and other networking hardware to forward the frame appropriately within the local network. The MAC address is crucial for ensuring that the data is delivered to the correct device, making it a vital component of Ethernet communication.