1A:90:21:00:00:00 to 1A:90:21:FF:FF:FF
Physical Security Interoperability Alliance
Inspect this prefixRegistered address
65 Washington St. Suite 170
Santa Clara CA 95050
Block details
- Registry
- CID, Company ID (CID)
- Prefix
- 1A:90:21 /24
- Addresses in block
- 16,777,216
- Decimal range
- 29,206,331,260,928 to 29,206,348,038,143
- Address type
- Unicast, locally administered
What this block covers
A 24 bit identifier that looks like an OUI but is explicitly not for globally unique addresses. The local bit is set, so CID addresses are locally administered by definition.
Any MAC address between 1A:90:21:00:00:00 and 1A:90:21:FF:FF:FF belongs to this assignment. The registrant chooses the remaining 24 bits, so the same prefix can appear on very different products from the same company.