Which company owns MAC address prefix CC:5D:57?

MAC address prefix CC:5D:57 is registered to Information System Research Institute,Inc. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with CC:5D:57 has a network interface built by Information System Research Institute,Inc..

What is the OUI CC:5D:57?

CC:5D:57 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Information System Research Institute,Inc.. It covers every address from CC:5D:57:00:00:00 to CC:5D:57:FF:FF:FF, or 16,777,216 addresses in total. It is also written CC-5D-57.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in CC:5D:57:00:00:00 that is CC:5D:57 — 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 Information System Research Institute,Inc. located?

Information System Research Institute,Inc. is listed at Metro city minamiikebukuro-bldg.5F Toshima-ku Tokyo JP 171-0022 in the IEEE OUI registry entry for CC:5D:57. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Information System Research Institute,Inc.

MAC address prefix CC:5D:57 is registered to Information System Research Institute,Inc. in the IEEE OUI registry. Any device whose MAC address begins with CC:5D:57 has a network interface built by Information System Research Institute,Inc.. 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 CC:5D:57:00:00:00 to CC:5D:57:FF:FF:FF.

OUI prefix: CC:5D:57
Hyphen form: CC-5D-57
MAC range: CC:5D:57:00:00:00 – CC:5D:57:FF:FF:FF
Addresses in block: 16,777,216
Organization: Information System Research Institute,Inc.
Address: Metro city minamiikebukuro-bldg.5F Toshima-ku Tokyo JP 171-0022
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 "Information System Research Institute,Inc."
archived source →
2026-07-17Assigned to "Information System Research Institute,Inc."

Nearby in the registry

The prefixes assigned immediately before and after CC:5D:57:

FAQ

Which company owns MAC address prefix CC:5D:57?: MAC address prefix CC:5D:57 is registered to Information System Research Institute,Inc. in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with CC:5D:57 has a network interface built by Information System Research Institute,Inc..
What is the OUI CC:5D:57?: CC:5D:57 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Information System Research Institute,Inc.. It covers every address from CC:5D:57:00:00:00 to CC:5D:57:FF:FF:FF, or 16,777,216 addresses in total. It is also written CC-5D-57.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in CC:5D:57:00:00:00 that is CC:5D:57 — 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 Information System Research Institute,Inc. located?: Information System Research Institute,Inc. is listed at Metro city minamiikebukuro-bldg.5F Toshima-ku Tokyo JP 171-0022 in the IEEE OUI registry entry for CC:5D:57. This is the address the organization registered with the IEEE, which may differ from its current operating address.