What this means
The IEEE assigned the MA-L block 903DBD to SECURE METERS 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 90:3D:BD, it is SECURE METERS LIMITED hardware.
Frequently Asked Questions
Who owns MAC prefix 903DBD?
903DBD is registered to SECURE METERS 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. SECURE METERS LIMITED's block covers 16,777,216 addresses.
What devices use 903DBD?
Any network device with a MAC address starting 90:3D:BD was manufactured by or for SECURE METERS LIMITED.