Who owns MAC prefix 0021CF?

0021CF is registered to The Crypto Group in the IEEE MA-L registry.

What devices use 0021CF?

Any network device with a MAC address starting 00:21:CF was manufactured by or for The Crypto Group.

MA-L · OUI prefix

The Crypto Group

Any MAC address starting 00:21:CF is registered to The Crypto Group in CH.

OUI prefix	0021CF
Vendor	The Crypto Group
Registry	MA-L (24-bit, large block)
Country	CH
Example MAC	00:21:CF:00:00:00

What this means

The IEEE assigned the MA-L block 0021CF to The Crypto Group. 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:CF, it is The Crypto Group hardware.

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