What this means
The IEEE assigned the MA-L block F4B3B1 to Silicon Laboratories. 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 F4:B3:B1, it is Silicon Laboratories hardware.
Frequently Asked Questions
Who owns MAC prefix F4B3B1?
F4B3B1 is registered to Silicon Laboratories 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. Silicon Laboratories's block covers 16,777,216 addresses.
What devices use F4B3B1?
Any network device with a MAC address starting F4:B3:B1 was manufactured by or for Silicon Laboratories.