Tyco Telecommunications

Any device whose MAC address begins with 00:21:B0 has a network interface built by Tyco Telecommunications. This prefix (the OUI, or Organizationally Unique Identifier) is assigned by the IEEE and is the first three octets of the address.

OUI prefix

00:21:B0

Organization

Tyco Telecommunications

Address

1011 Pawtucket Blvd Lowell Massachusetts US 01853

Source

IEEE OUI registry

Have a full MAC address? Look it up— we'll also tell you if it's a randomized (private) address rather than a real manufacturer prefix.