Which company owns MAC address prefix 20:AA:4B?

MAC address prefix 20:AA:4B is registered to Cisco-Linksys, LLC in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 20:AA:4B has a network interface built by Cisco-Linksys, LLC.

What is the OUI 20:AA:4B?

20:AA:4B is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Cisco-Linksys, LLC. It covers every address from 20:AA:4B:00:00:00 to 20:AA:4B:FF:FF:FF, or 16,777,216 addresses in total. It is also written 20-AA-4B.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in 20:AA:4B:00:00:00 that is 20:AA:4B — 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 Cisco-Linksys, LLC located?

Cisco-Linksys, LLC is listed at 121 Theory Drive Irvine California US 92612 in the IEEE OUI registry entry for 20:AA:4B. This is the address the organization registered with the IEEE, which may differ from its current operating address.

How many MAC prefixes does Cisco-Linksys, LLC own?

Cisco-Linksys, LLC holds 25 OUI prefixes in the IEEE registry, of which 20:AA:4B is one. A device made by Cisco-Linksys, LLC could carry a MAC address from any of them.

Cisco-Linksys, LLC

MAC address prefix 20:AA:4B is registered to Cisco-Linksys, LLC in the IEEE OUI registry. Any device whose MAC address begins with 20:AA:4B has a network interface built by Cisco-Linksys, LLC. 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 20:AA:4B:00:00:00 to 20:AA:4B:FF:FF:FF.

OUI prefix: 20:AA:4B
Hyphen form: 20-AA-4B
MAC range: 20:AA:4B:00:00:00 – 20:AA:4B:FF:FF:FF
Addresses in block: 16,777,216
Organization: Cisco-Linksys, LLC
Address: 121 Theory Drive Irvine California US 92612
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 Cisco-Linksys, LLC

Cisco-Linksys, LLC holds 25 OUI prefixes in total. A device with this exact prefix could just as well carry any of these:

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 "Cisco-Linksys, LLC"
archived source →
2026-07-17Assigned to "Cisco-Linksys, LLC"

Nearby in the registry

The prefixes assigned immediately before and after 20:AA:4B:

FAQ

Which company owns MAC address prefix 20:AA:4B?: MAC address prefix 20:AA:4B is registered to Cisco-Linksys, LLC in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 20:AA:4B has a network interface built by Cisco-Linksys, LLC.
What is the OUI 20:AA:4B?: 20:AA:4B is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Cisco-Linksys, LLC. It covers every address from 20:AA:4B:00:00:00 to 20:AA:4B:FF:FF:FF, or 16,777,216 addresses in total. It is also written 20-AA-4B.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in 20:AA:4B:00:00:00 that is 20:AA:4B — 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 Cisco-Linksys, LLC located?: Cisco-Linksys, LLC is listed at 121 Theory Drive Irvine California US 92612 in the IEEE OUI registry entry for 20:AA:4B. This is the address the organization registered with the IEEE, which may differ from its current operating address.
How many MAC prefixes does Cisco-Linksys, LLC own?: Cisco-Linksys, LLC holds 25 OUI prefixes in the IEEE registry, of which 20:AA:4B is one. A device made by Cisco-Linksys, LLC could carry a MAC address from any of them.