General Engine Management Systems Ltd.

Any device whose MAC address begins with 90:20:83 has a network interface built by General Engine Management Systems Ltd.. This prefix (the OUI, or Organizationally Unique Identifier) is assigned by the IEEE and is the first three octets of the address.

OUI prefix

90:20:83

Organization

General Engine Management Systems Ltd.

Address

GEMS Egham Surrey GB TW208RN

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.