What this means
The IEEE assigned the MA-L block 001B7C to A & R Cambridge. 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 00:1B:7C, it is A & R Cambridge hardware.
Frequently Asked Questions
Who owns MAC prefix 001B7C?
001B7C is registered to A & R Cambridge 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. A & R Cambridge's block covers 16,777,216 addresses.
What devices use 001B7C?
Any network device with a MAC address starting 00:1B:7C was manufactured by or for A & R Cambridge.