What this means
The IEEE assigned the MA-L block 18B591 to I-Storm. 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 18:B5:91, it is I-Storm hardware.
Frequently Asked Questions
Who owns MAC prefix 18B591?
18B591 is registered to I-Storm in the IEEE MA-L registry.
What does the MA-L registry type mean?
An MA-L assignment, the IEEE's original OUI format, gives the vendor the first three octets and 16,777,216 device addresses under them. I-Storm's block covers 16,777,216 addresses.
What devices use 18B591?
Any network device with a MAC address starting 18:B5:91 was manufactured by or for I-Storm.