00:21:57 National Datacast, Inc.
Every MAC address from 00:21:57:00:00:00 to 00:21:57:FF:FF:FF belongs to a block the IEEE assigned to National Datacast, Inc.. Network cards, phones and other devices it makes carry addresses from here.
Assignment
Who 00:21:57 belongs to
Written 00:21:57, 00-21-57 or 002157, depending on the system. Look up a full address.
Prefix
00:21:57
Organization
National Datacast, Inc.
Registry
MA-L (a 24-bit OUI)
Addresses
16,777,216
First address
00:21:57:00:00:00
Last address
00:21:57:FF:FF:FF
Address type
Globally unique, unicast
Registered address
2100 Crystal Drive, Suite 750 Arlington VA US 22202