What this means
The IEEE assigned the MA-L block 0021C1 to ABB Oy / Medium Voltage Products. 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 00:21:C1, it is ABB Oy / Medium Voltage Products hardware.
Frequently Asked Questions
Who owns MAC prefix 0021C1?
0021C1 is registered to ABB Oy / Medium Voltage Products 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. ABB Oy / Medium Voltage Products's block covers 16,777,216 addresses.
What devices use 0021C1?
Any network device with a MAC address starting 00:21:C1 was manufactured by or for ABB Oy / Medium Voltage Products.