Which company owns MAC address prefix 34:EF:8B?

MAC address prefix 34:EF:8B is registered to NTT DOCOMO BUSINESS, Inc. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 34:EF:8B has a network interface built by NTT DOCOMO BUSINESS, Inc..

What is the OUI 34:EF:8B?

34:EF:8B is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to NTT DOCOMO BUSINESS, Inc.. It covers every address from 34:EF:8B:00:00:00 to 34:EF:8B:FF:FF:FF, or 16,777,216 addresses in total. It is also written 34-EF-8B.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 34:EF:8B:00:00:00 that is 34:EF:8B — 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 NTT DOCOMO BUSINESS, Inc. located?

NTT DOCOMO BUSINESS, Inc. is listed at NTT DOCOMO BUSINESS Karagasaki Bldg. 1-11-7 Chuo-cho Meguro-ku Tokyo JP 152-0001 in the IEEE OUI registry entry for 34:EF:8B. This is the address the organization registered with the IEEE, which may differ from its current operating address.

NTT DOCOMO BUSINESS, Inc.

MAC address prefix 34:EF:8B is registered to NTT DOCOMO BUSINESS, Inc. in the IEEE OUI registry. Any device whose MAC address begins with 34:EF:8B has a network interface built by NTT DOCOMO BUSINESS, Inc.. 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 34:EF:8B:00:00:00 to 34:EF:8B:FF:FF:FF.

OUI prefix: 34:EF:8B
Hyphen form: 34-EF-8B
MAC range: 34:EF:8B:00:00:00 – 34:EF:8B:FF:FF:FF
Addresses in block: 16,777,216
Organization: NTT DOCOMO BUSINESS, Inc.
Address: NTT DOCOMO BUSINESS Karagasaki Bldg. 1-11-7 Chuo-cho Meguro-ku Tokyo JP 152-0001
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 (3)

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 "NTT Communications Corporation"
archived source →
2026-01-08Renamed from "NTT Communications Corporation" to "NTT DOCOMO BUSINESS, Inc."
archived source →
2026-07-17Assigned to "NTT DOCOMO BUSINESS, Inc."

Nearby in the registry

The prefixes assigned immediately before and after 34:EF:8B:

FAQ

Which company owns MAC address prefix 34:EF:8B?: MAC address prefix 34:EF:8B is registered to NTT DOCOMO BUSINESS, Inc. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 34:EF:8B has a network interface built by NTT DOCOMO BUSINESS, Inc..
What is the OUI 34:EF:8B?: 34:EF:8B is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to NTT DOCOMO BUSINESS, Inc.. It covers every address from 34:EF:8B:00:00:00 to 34:EF:8B:FF:FF:FF, or 16,777,216 addresses in total. It is also written 34-EF-8B.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 34:EF:8B:00:00:00 that is 34:EF:8B — 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 NTT DOCOMO BUSINESS, Inc. located?: NTT DOCOMO BUSINESS, Inc. is listed at NTT DOCOMO BUSINESS Karagasaki Bldg. 1-11-7 Chuo-cho Meguro-ku Tokyo JP 152-0001 in the IEEE OUI registry entry for 34:EF:8B. This is the address the organization registered with the IEEE, which may differ from its current operating address.