What this means
The IEEE assigned the MA-L block 90E5B1 to Espressif Inc.. 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 90:E5:B1, it is Espressif Inc. hardware.
Frequently Asked Questions
Who owns MAC prefix 90E5B1?
90E5B1 is registered to Espressif Inc. 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. Espressif Inc.'s block covers 16,777,216 addresses.
What devices use 90E5B1?
Any network device with a MAC address starting 90:E5:B1 was manufactured by or for Espressif Inc..