Rockwell Automation

Any device whose MAC address begins with E4:90:69 has a network interface built by Rockwell Automation. This prefix (the OUI, or Organizationally Unique Identifier) is assigned by the IEEE and is the first three octets of the address.

OUI prefix

E4:90:69

Organization

Rockwell Automation

Address

1 Allen-Bradley Dr. Mayfield Heights OH US 44124-6118

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.