Which company owns MAC address prefix 04:D6:34?

MAC address prefix 04:D6:34 is registered to Nanjing RISC-V Institute Co., Ltd. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 04:D6:34 has a network interface built by Nanjing RISC-V Institute Co., Ltd..

What is the OUI 04:D6:34?

04:D6:34 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Nanjing RISC-V Institute Co., Ltd.. It covers every address from 04:D6:34:00:00:00 to 04:D6:34:FF:FF:FF, or 16,777,216 addresses in total. It is also written 04-D6-34.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 04:D6:34:00:00:00 that is 04:D6:34 — 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 Nanjing RISC-V Institute Co., Ltd. located?

Nanjing RISC-V Institute Co., Ltd. is listed at Room 303, Building C, 18 Ningshuang Road Nanjing Jiangsu CN 210000 in the IEEE OUI registry entry for 04:D6:34. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Nanjing RISC-V Institute Co., Ltd.

MAC address prefix 04:D6:34 is registered to Nanjing RISC-V Institute Co., Ltd. in the IEEE OUI registry. Any device whose MAC address begins with 04:D6:34 has a network interface built by Nanjing RISC-V Institute 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 04:D6:34:00:00:00 to 04:D6:34:FF:FF:FF.

OUI prefix: 04:D6:34
Hyphen form: 04-D6-34
MAC range: 04:D6:34:00:00:00 – 04:D6:34:FF:FF:FF
Addresses in block: 16,777,216
Organization: Nanjing RISC-V Institute Co., Ltd.
Address: Room 303, Building C, 18 Ningshuang Road Nanjing Jiangsu CN 210000
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 (1)

The IEEE registry publishes current state only — this is the change record we've kept since we started tracking it daily.

2026-08-13Assigned to "Nanjing RISC-V Institute Co., Ltd."

Nearby in the registry

The prefixes assigned immediately before and after 04:D6:34:

FAQ

Which company owns MAC address prefix 04:D6:34?: MAC address prefix 04:D6:34 is registered to Nanjing RISC-V Institute Co., Ltd. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 04:D6:34 has a network interface built by Nanjing RISC-V Institute Co., Ltd..
What is the OUI 04:D6:34?: 04:D6:34 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Nanjing RISC-V Institute Co., Ltd.. It covers every address from 04:D6:34:00:00:00 to 04:D6:34:FF:FF:FF, or 16,777,216 addresses in total. It is also written 04-D6-34.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 04:D6:34:00:00:00 that is 04:D6:34 — 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 Nanjing RISC-V Institute Co., Ltd. located?: Nanjing RISC-V Institute Co., Ltd. is listed at Room 303, Building C, 18 Ningshuang Road Nanjing Jiangsu CN 210000 in the IEEE OUI registry entry for 04:D6:34. This is the address the organization registered with the IEEE, which may differ from its current operating address.