I hope this was the right place to post this, sorry if it isn't. Also, I know next to nothing about networks. I'm trying to allocate bandwidth to different devices on my Linksys E1200 router. When I check my computer's MAC address, it comes back as 74:E5:0B:10:01:04. I turned off everything in my apartment besides my xbox and notebook, and under the DHCP client table under my router settings I see the xbox along with "Owner-PC" and a MAC address of 00:21:6B:10:A8:6E. Is this my computer, and if so, why are there different MAC addresses?
MAC Addresses are NIC specific.. Each Network Interface will have its own MAC Address. So a modern computer with support for Wired Network (LAN Interface) as well as other types of network connectivity like Wireless Network (WiFi) will obviously have multiple MAC Addresses, one for each Network interface.
If your computer is connecting to the router via WiFi, check the MAC address of your WiFi card. If on Windows, simply run ipconfig /all on command line interface (command prompt), you should be able to see MAC Address (Physical Address) for each network interface.
来源：https://stackoverflow.com/questions/26583712/can-one-computer-have-two-mac-addresses