What this means
The IEEE assigned the MA-M block 500B91B to thumbzup UK Limited. 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 50:0B:91:B, it is thumbzup UK Limited hardware.
Frequently Asked Questions
Who owns MAC prefix 500B91B?
500B91B is registered to thumbzup UK Limited in the IEEE MA-M registry.
What does the MA-M registry type mean?
An MA-M assignment covers 28 bits of the address, giving the vendor 1,048,576 device addresses, a quarter of a full MA-L block. thumbzup UK Limited's block covers 1,048,576 addresses.
What devices use 500B91B?
Any network device with a MAC address starting 50:0B:91:B was manufactured by or for thumbzup UK Limited.