Which company owns MAC address prefix C0:27:B9?

MAC address prefix C0:27:B9 is registered to Beijing National Railway Research & Design Institute of Signal & Communication Co., Ltd. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with C0:27:B9 has a network interface built by Beijing National Railway Research & Design Institute of Signal & Communication Co., Ltd..

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in C0:27:B9:00:00:00 that is C0:27:B9 — 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.

Beijing National Railway Research & Design Institute of Signal & Communication Co., Ltd.

MAC address prefix C0:27:B9 is registered to Beijing National Railway Research & Design Institute of Signal & Communication Co., Ltd. in the IEEE OUI registry. Any device whose MAC address begins with C0:27:B9 has a network interface built by Beijing National Railway Research & Design Institute of Signal & Communication Co., Ltd.. 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 C0:27:B9:00:00:00 to C0:27:B9:FF:FF:FF.

OUI prefix: C0:27:B9
Hyphen form: C0-27-B9
MAC range: C0:27:B9:00:00:00 – C0:27:B9:FF:FF:FF
Addresses in block: 16,777,216
Organization: Beijing National Railway Research & Design Institute of Signal & Communication Co., Ltd.
Address: Building No.18, Huayuan YiLi,Fengtai District, Beijing CN 100073
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 "Beijing National Railway Research & Design Institute of Signal & Communication Co., Ltd."
archived source →
2026-07-17Assigned to "Beijing National Railway Research & Design Institute of Signal & Communication Co., Ltd."

Nearby in the registry

The prefixes assigned immediately before and after C0:27:B9:

FAQ

Which company owns MAC address prefix C0:27:B9?: MAC address prefix C0:27:B9 is registered to Beijing National Railway Research & Design Institute of Signal & Communication Co., Ltd. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with C0:27:B9 has a network interface built by Beijing National Railway Research & Design Institute of Signal & Communication Co., Ltd..
What is the OUI C0:27:B9?: C0:27:B9 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Beijing National Railway Research & Design Institute of Signal & Communication Co., Ltd.. It covers every address from C0:27:B9:00:00:00 to C0:27:B9:FF:FF:FF, or 16,777,216 addresses in total. It is also written C0-27-B9.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in C0:27:B9:00:00:00 that is C0:27:B9 — 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 Beijing National Railway Research & Design Institute of Signal & Communication Co., Ltd. located?: Beijing National Railway Research & Design Institute of Signal & Communication Co., Ltd. is listed at Building No.18, Huayuan YiLi,Fengtai District, Beijing CN 100073 in the IEEE OUI registry entry for C0:27:B9. This is the address the organization registered with the IEEE, which may differ from its current operating address.