Who owns MAC prefix A4251B?

A4251B is registered to Avaya Inc in the IEEE MA-L registry.

What devices use A4251B?

Any network device with a MAC address starting A4:25:1B was manufactured by or for Avaya Inc.

MA-L · OUI prefix

Avaya Inc

Any MAC address starting A4:25:1B is registered to Avaya Inc in US.

OUI prefix	A4251B
Vendor	Avaya Inc
Registry	MA-L (24-bit, large block)
Country	US
Example MAC	A4:25:1B:00:00:00

What this means

The IEEE assigned the MA-L block A4251B to Avaya Inc. 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 A4:25:1B, it is Avaya Inc hardware.

Other Avaya Inc prefixes

Avaya Inc holds 52 registered blocks in total.

00040D 001B4F 00549F 048A15 10CDAE 14612F 24B209 24D921 2CF4C5 3475C7 38BB3C 3C3A73 all 52 »

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