National Datacomputer
MAC address prefix 00:05:89 is registered to National Datacomputer in the IEEE OUI registry. Any device whose MAC address begins with 00:05:89 has a network interface built by National Datacomputer. 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 00:05:89:00:00:00 to 00:05:89:FF:FF:FF.
- OUI prefix
- 00:05:89
- Hyphen form
- 00-05-89
- MAC range
- 00:05:89:00:00:00 – 00:05:89:FF:FF:FF
- Addresses in block
- 16,777,216
- Organization
- National Datacomputer
- Address
- 900 Middlesex Tpk. Billerica MA US 01821
- 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 "National Datacomputer"archived source →
- 2026-07-17Assigned to "National Datacomputer"
Nearby in the registry
The prefixes assigned immediately before and after 00:05:89:
- ImageCom Limited00:05:83
- AbsoluteValue Systems, Inc.00:05:84
- Juniper Networks00:05:85
- Lucent Technologies00:05:86
- Locus, Incorporated00:05:87
- Sensoria Corp.00:05:88
- Netcom Co., Ltd.00:05:8A
- IPmental, Inc.00:05:8B
- Opentech Inc.00:05:8C
- Lynx Photonic Networks, Inc.00:05:8D
- Flextronics International GmbH & Co. Nfg. KG00:05:8E
- CLCsoft co.00:05:8F
FAQ
- Which company owns MAC address prefix 00:05:89?
- MAC address prefix 00:05:89 is registered to National Datacomputer in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with 00:05:89 has a network interface built by National Datacomputer.
- What is the OUI 00:05:89?
- 00:05:89 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to National Datacomputer. It covers every address from 00:05:89:00:00:00 to 00:05:89:FF:FF:FF, or 16,777,216 addresses in total. It is also written 00-05-89.
- How do I find the manufacturer of a MAC address?
- Take the first three octets of the address — in 00:05:89:00:00:00 that is 00:05:89 — 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 National Datacomputer located?
- National Datacomputer is listed at 900 Middlesex Tpk. Billerica MA US 01821 in the IEEE OUI registry entry for 00:05:89. This is the address the organization registered with the IEEE, which may differ from its current operating address.