What this means
The IEEE assigned the MA-L block 001521 to Horoquartz. 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 00:15:21, it is Horoquartz hardware.
Frequently Asked Questions
Who owns MAC prefix 001521?
001521 is registered to Horoquartz 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. Horoquartz's block covers 16,777,216 addresses.
What devices use 001521?
Any network device with a MAC address starting 00:15:21 was manufactured by or for Horoquartz.