Which company owns MAC address prefix 78:EF:4C?

MAC address prefix 78:EF:4C is registered to Unetconvergence Co., Ltd. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 78:EF:4C has a network interface built by Unetconvergence Co., Ltd..

What is the OUI 78:EF:4C?

78:EF:4C is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Unetconvergence Co., Ltd.. It covers every address from 78:EF:4C:00:00:00 to 78:EF:4C:FF:FF:FF, or 16,777,216 addresses in total. It is also written 78-EF-4C.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 78:EF:4C:00:00:00 that is 78:EF:4C — 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 Unetconvergence Co., Ltd. located?

Unetconvergence Co., Ltd. is listed at 101-511, Digital Empire2, 486, Shin-dong, Youngtong-gu Suwon Kyonggi-do KR 443-390 in the IEEE OUI registry entry for 78:EF:4C. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Unetconvergence Co., Ltd.

MAC address prefix 78:EF:4C is registered to Unetconvergence Co., Ltd. in the IEEE OUI registry. Any device whose MAC address begins with 78:EF:4C has a network interface built by Unetconvergence 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 78:EF:4C:00:00:00 to 78:EF:4C:FF:FF:FF.

OUI prefix: 78:EF:4C
Hyphen form: 78-EF-4C
MAC range: 78:EF:4C:00:00:00 – 78:EF:4C:FF:FF:FF
Addresses in block: 16,777,216
Organization: Unetconvergence Co., Ltd.
Address: 101-511, Digital Empire2, 486, Shin-dong, Youngtong-gu Suwon Kyonggi-do KR 443-390
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 "Unetconvergence Co., Ltd."
archived source →
2026-07-17Assigned to "Unetconvergence Co., Ltd."

Nearby in the registry

The prefixes assigned immediately before and after 78:EF:4C:

FAQ

Which company owns MAC address prefix 78:EF:4C?: MAC address prefix 78:EF:4C is registered to Unetconvergence Co., Ltd. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 78:EF:4C has a network interface built by Unetconvergence Co., Ltd..
What is the OUI 78:EF:4C?: 78:EF:4C is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Unetconvergence Co., Ltd.. It covers every address from 78:EF:4C:00:00:00 to 78:EF:4C:FF:FF:FF, or 16,777,216 addresses in total. It is also written 78-EF-4C.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 78:EF:4C:00:00:00 that is 78:EF:4C — 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 Unetconvergence Co., Ltd. located?: Unetconvergence Co., Ltd. is listed at 101-511, Digital Empire2, 486, Shin-dong, Youngtong-gu Suwon Kyonggi-do KR 443-390 in the IEEE OUI registry entry for 78:EF:4C. This is the address the organization registered with the IEEE, which may differ from its current operating address.