28:B7:7C:5 GROTHE GmbH
Every MAC address from 28:B7:7C:50:00:00 to 28:B7:7C:5F:FF:FF belongs to a block the IEEE assigned to GROTHE GmbH. Network cards, phones and other devices it makes carry addresses from here.
Assignment
Who 28:B7:7C:5 belongs to
Written 28:B7:7C:5, 28-B7-7C-5 or 28B77C5, depending on the system. Look up a full address.
Prefix
28:B7:7C:5/28
Organization
GROTHE GmbH
Registry
MA-M (28 bits)
Addresses
1,048,576
First address
28:B7:7C:50:00:00
Last address
28:B7:7C:5F:FF:FF
Address type
Globally unique, unicast
Registered address
Loehestrasse 22 Hennef DE 53773
Parent block
Inside 28:B7:7C
This MA-M block is carved from the 24-bit block 28:B7:7C, which the IEEE holds as IEEE Registration Authority and divides among smaller assignees.