Telecommunications Industry Association TR-41 Committee

MA-L

MA-L: a full /24 OUI block, IEEE's largest, covering 16,777,216 addresses.

Prefix00:12:BB:00:00:00 /24

Vendor address2500 Wilson Blvd., Suite 300 Arlington VA US 22201

RegisteredNov 16, 2004

Block range00:12:BB:00:00:00– 00:12:BB:FF:FF:FF

Address capacity16,777,216

AdministrationUniversally administered: its prefix comes from a block registered through the IEEE Registration Authority

TransmissionUnicast: addressed to a single device

SourceIEEE Registration Authority

Address capacity is the size of this registered block, not a count of devices actually manufactured or online. Registration identifies the organization holding the block, not a specific device model or unit.

Curious how a prefix like this turns into a full address? See how MAC addresses are structured →

Example addresses in this block

00:12:BB:00:00:00 00:12:BB:7F:FF:FF 00:12:BB:FF:FF:FF

Where this block sits

Previous 00:12:BA:00:00:00 /24 FSI Systems, Inc. Next 00:12:BC:00:00:00 /24 Echolab LLC

The nearest registered blocks of the same size on either side of this one in IEEE's address space.

Telecommunications Industry Association TR-41 Committee holds 1 registered blocks in the IEEE registry, ranking #29,521 of 33,427 organizations by block count.