What this means
The IEEE assigned the MA-L block 281D21 to IN ONE SMART TECHNOLOGY(H,K,)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 28:1D:21, it is IN ONE SMART TECHNOLOGY(H,K,)LIMITED hardware.
Frequently Asked Questions
Who owns MAC prefix 281D21?
281D21 is registered to IN ONE SMART TECHNOLOGY(H,K,)LIMITED 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. IN ONE SMART TECHNOLOGY(H,K,)LIMITED's block covers 16,777,216 addresses.
What devices use 281D21?
Any network device with a MAC address starting 28:1D:21 was manufactured by or for IN ONE SMART TECHNOLOGY(H,K,)LIMITED.