IEEE Registration Authority
MAC address prefix B0:C5:CA is registered to IEEE Registration Authority in the IEEE OUI registry. Any device whose MAC address begins with B0:C5:CA has a network interface built by IEEE Registration Authority. This prefix (the OUI, or Organizationally Unique Identifier) is assigned by the IEEE and is the first three octets of the address — it covers every MAC from B0:C5:CA:00:00:00 to B0:C5:CA:FF:FF:FF.
- OUI prefix
- B0:C5:CA
- Hyphen form
- B0-C5-CA
- MAC range
- B0:C5:CA:00:00:00 – B0:C5:CA:FF:FF:FF
- Addresses in block
- 16,777,216
- Organization
- IEEE Registration Authority
- Address
- 445 Hoes Lane Piscataway NJ US 08554
- Source
- IEEE OUI registry
Have a full MAC address? Look it up— we'll also tell you if it's a randomized (private) address rather than a real manufacturer prefix.
Assignment history (2)
The IEEE registry publishes current state only — this is the change record we've kept since we started tracking it daily.
- 2016-07-29Assigned to "IEEE Registration Authority"archived source →
- 2026-07-17Assigned to "IEEE Registration Authority"
Nearby in the registry
The prefixes assigned immediately before and after B0:C5:CA:
- Huawei Device Co., Ltd.B0:C3:8E
- SenseitB0:C4:6C
- Samsung Electronics Co.,LtdB0:C4:E7
- Cisco Systems, IncB0:C5:3C
- D-Link InternationalB0:C5:54
- Samsung Electronics Co.,LtdB0:C5:59
- HUAWEI TECHNOLOGIES CO.,LTDB0:C6:1C
- Juniper NetworksB0:C6:9A
- BUFFALO.INCB0:C7:45
- HUAWEI TECHNOLOGIES CO.,LTDB0:C7:87
- Silicon LaboratoriesB0:C7:DE
- Jiangsu Cynray IOT Co., Ltd.B0:C8:3F
FAQ
- Which company owns MAC address prefix B0:C5:CA?
- MAC address prefix B0:C5:CA is registered to IEEE Registration Authority in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with B0:C5:CA has a network interface built by IEEE Registration Authority.
- What is the OUI B0:C5:CA?
- B0:C5:CA is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to IEEE Registration Authority. It covers every address from B0:C5:CA:00:00:00 to B0:C5:CA:FF:FF:FF, or 16,777,216 addresses in total. It is also written B0-C5-CA.
- How do I find the manufacturer of a MAC address?
- Take the first three octets of the address — in B0:C5:CA:00:00:00 that is B0:C5:CA — and look that prefix up in the IEEE OUI registry. If the second-lowest bit of the first octet is set, the address is locally administered (a randomized or private MAC), which belongs to no manufacturer and will not resolve; modern phones and laptops use these by default on each network.
- Where is IEEE Registration Authority located?
- IEEE Registration Authority is listed at 445 Hoes Lane Piscataway NJ US 08554 in the IEEE OUI registry entry for B0:C5:CA. This is the address the organization registered with the IEEE, which may differ from its current operating address.