Which company owns MAC address prefix D8:AF:81?

MAC address prefix D8:AF:81 is registered to AO in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with D8:AF:81 has a network interface built by AO.

What is the OUI D8:AF:81?

D8:AF:81 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to AO. It covers every address from D8:AF:81:00:00:00 to D8:AF:81:FF:FF:FF, or 16,777,216 addresses in total. It is also written D8-AF-81.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in D8:AF:81:00:00:00 that is D8:AF:81 — 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.

AO is listed at Filippovskiy per., 8/1 Moscow RU 119019 in the IEEE OUI registry entry for D8:AF:81. This is the address the organization registered with the IEEE, which may differ from its current operating address.

How many MAC prefixes does AO own?

AO holds 4 OUI prefixes in the IEEE registry, of which D8:AF:81 is one. A device made by AO could carry a MAC address from any of them.

AO

MAC address prefix D8:AF:81 is registered to AO in the IEEE OUI registry. Any device whose MAC address begins with D8:AF:81 has a network interface built by AO. 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 D8:AF:81:00:00:00 to D8:AF:81:FF:FF:FF.

OUI prefix: D8:AF:81
Hyphen form: D8-AF-81
MAC range: D8:AF:81:00:00:00 – D8:AF:81:FF:FF:FF
Addresses in block: 16,777,216
Organization: AO
Address: Filippovskiy per., 8/1 Moscow RU 119019
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.

Other prefixes from AO

AO holds 4 OUI prefixes in total. A device with this exact prefix could just as well carry any of these:

Assignment history (3)

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

2019-07-04Assigned to "ZAO "NPK Rotek""
archived source →
2023-07-11Renamed from "ZAO "NPK Rotek"" to "AO"
archived source →
2026-07-17Assigned to "AO"

Nearby in the registry

The prefixes assigned immediately before and after D8:AF:81:

FAQ

Which company owns MAC address prefix D8:AF:81?: MAC address prefix D8:AF:81 is registered to AO in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with D8:AF:81 has a network interface built by AO.
What is the OUI D8:AF:81?: D8:AF:81 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to AO. It covers every address from D8:AF:81:00:00:00 to D8:AF:81:FF:FF:FF, or 16,777,216 addresses in total. It is also written D8-AF-81.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in D8:AF:81:00:00:00 that is D8:AF:81 — 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 AO located?: AO is listed at Filippovskiy per., 8/1 Moscow RU 119019 in the IEEE OUI registry entry for D8:AF:81. This is the address the organization registered with the IEEE, which may differ from its current operating address.
How many MAC prefixes does AO own?: AO holds 4 OUI prefixes in the IEEE registry, of which D8:AF:81 is one. A device made by AO could carry a MAC address from any of them.