Dictionary · Networking Fundamentals
MAC Address
MAC — Media Access Control
Addressing · Beginner
A hardware address used on a local link, commonly 48 bits and written in hexadecimal. Switches learn which port reaches which hardware address.
Inside one local network, devices deliver frames to this burned-in or configured hardware address. It does not, by itself, tell routers how to reach a host across the Internet.
Example: A switch table maps 00:1A:2B:3C:4D:5E to port 12, so frames for that host leave that port.
Common misconception
- This hardware address is not the same as an Internet address, and it is not a reliable identity once traffic crosses a router.