ISDN SYSTEMS CORPORATION

Any device whose MAC address begins with 00:20:69 has a network interface built by ISDN SYSTEMS CORPORATION. This prefix (the OUI, or Organizationally Unique Identifier) is assigned by the IEEE and is the first three octets of the address.

OUI prefix

00:20:69

Organization

ISDN SYSTEMS CORPORATION

Address

8320 OLD COURTHOUSE RD. VIENNA VA US 22182

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.