Union Business Machines Co. Ltd.

Any device whose MAC address begins with 00:23:79 has a network interface built by Union Business Machines Co. 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

00:23:79

Organization

Union Business Machines Co. Ltd.

Address

Unit 2, 2/F, Block A, Hong Kong Industrial Centre, Lai Chi Kok Kowloon HK

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.