What this means
The IEEE assigned the MA-L block 004003 to Emerson Process Management Power & Water Solutions, Inc.. Every network interface they manufacture under this block has a MAC address beginning with these digits, followed by a unique per-device identifier. If a device on your network shows a MAC starting 00:40:03, it is Emerson Process Management Power & Water Solutions, Inc. hardware.
Frequently Asked Questions
Who owns MAC prefix 004003?
004003 is registered to Emerson Process Management Power & Water Solutions, Inc. in the IEEE MA-L registry.
What does the MA-L registry type mean?
An MA-L assignment, the IEEE's original OUI format, gives the vendor the first three octets and 16,777,216 device addresses under them. Emerson Process Management Power & Water Solutions, Inc.'s block covers 16,777,216 addresses.
What devices use 004003?
Any network device with a MAC address starting 00:40:03 was manufactured by or for Emerson Process Management Power & Water Solutions, Inc..