What this means
The IEEE assigned the MA-M block 40ED987 to Vaisala Oyj. 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 40:ED:98:7, it is Vaisala Oyj hardware.
Frequently Asked Questions
Who owns MAC prefix 40ED987?
40ED987 is registered to Vaisala Oyj 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. Vaisala Oyj's block covers 1,048,576 addresses.
What devices use 40ED987?
Any network device with a MAC address starting 40:ED:98:7 was manufactured by or for Vaisala Oyj.