What this means
The IEEE assigned the MA-L block B858FF to Arista Networks. 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 B8:58:FF, it is Arista Networks hardware.
Frequently Asked Questions
Who owns MAC prefix B858FF?
B858FF is registered to Arista Networks 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. Arista Networks's block covers 16,777,216 addresses.
What devices use B858FF?
Any network device with a MAC address starting B8:58:FF was manufactured by or for Arista Networks.