Which company owns MAC address prefix 84:96:81?

MAC address prefix 84:96:81 is registered to Cathay Communication Co.,Ltd in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 84:96:81 has a network interface built by Cathay Communication Co.,Ltd.

What is the OUI 84:96:81?

84:96:81 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Cathay Communication Co.,Ltd. It covers every address from 84:96:81:00:00:00 to 84:96:81:FF:FF:FF, or 16,777,216 addresses in total. It is also written 84-96-81.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 84:96:81:00:00:00 that is 84:96:81 — 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 Cathay Communication Co.,Ltd located?

Cathay Communication Co.,Ltd is listed at Tsinghua Institude A319 of Hi-tech Park,Nanshan district,Shenzhen China Shenzhen Canton CN 0755 in the IEEE OUI registry entry for 84:96:81. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Cathay Communication Co.,Ltd

MAC address prefix 84:96:81 is registered to Cathay Communication Co.,Ltd in the IEEE OUI registry. Any device whose MAC address begins with 84:96:81 has a network interface built by Cathay 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 84:96:81:00:00:00 to 84:96:81:FF:FF:FF.

OUI prefix: 84:96:81
Hyphen form: 84-96-81
MAC range: 84:96:81:00:00:00 – 84:96:81:FF:FF:FF
Addresses in block: 16,777,216
Organization: Cathay Communication Co.,Ltd
Address: Tsinghua Institude A319 of Hi-tech Park,Nanshan district,Shenzhen China Shenzhen Canton CN 0755
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 "Cathay Communication Co.,Ltd"
archived source →
2026-07-17Assigned to "Cathay Communication Co.,Ltd"

Nearby in the registry

The prefixes assigned immediately before and after 84:96:81:

FAQ

Which company owns MAC address prefix 84:96:81?: MAC address prefix 84:96:81 is registered to Cathay Communication Co.,Ltd in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 84:96:81 has a network interface built by Cathay Communication Co.,Ltd.
What is the OUI 84:96:81?: 84:96:81 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Cathay Communication Co.,Ltd. It covers every address from 84:96:81:00:00:00 to 84:96:81:FF:FF:FF, or 16,777,216 addresses in total. It is also written 84-96-81.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 84:96:81:00:00:00 that is 84:96:81 — 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 Cathay Communication Co.,Ltd located?: Cathay Communication Co.,Ltd is listed at Tsinghua Institude A319 of Hi-tech Park,Nanshan district,Shenzhen China Shenzhen Canton CN 0755 in the IEEE OUI registry entry for 84:96:81. This is the address the organization registered with the IEEE, which may differ from its current operating address.