Which company owns MAC address prefix EC:E5:55?

MAC address prefix EC:E5:55 is registered to Hirschmann Automation in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with EC:E5:55 has a network interface built by Hirschmann Automation.

What is the OUI EC:E5:55?

EC:E5:55 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Hirschmann Automation. It covers every address from EC:E5:55:00:00:00 to EC:E5:55:FF:FF:FF, or 16,777,216 addresses in total. It is also written EC-E5-55.

How do I find the manufacturer of a MAC address?

Take the first three octets of the address — in EC:E5:55:00:00:00 that is EC:E5:55 — 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 Hirschmann Automation located?

Hirschmann Automation is listed at Stuttgarter Straße 45-51 Neckartenzlingen Baden-Württemberg DE 72654 in the IEEE OUI registry entry for EC:E5:55. This is the address the organization registered with the IEEE, which may differ from its current operating address.

Hirschmann Automation

MAC address prefix EC:E5:55 is registered to Hirschmann Automation in the IEEE OUI registry. Any device whose MAC address begins with EC:E5:55 has a network interface built by Hirschmann Automation. 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 EC:E5:55:00:00:00 to EC:E5:55:FF:FF:FF.

OUI prefix: EC:E5:55
Hyphen form: EC-E5-55
MAC range: EC:E5:55:00:00:00 – EC:E5:55:FF:FF:FF
Addresses in block: 16,777,216
Organization: Hirschmann Automation
Address: Stuttgarter Straße 45-51 Neckartenzlingen Baden-Württemberg DE 72654
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 "Hirschmann Automation"
archived source →
2026-07-17Assigned to "Hirschmann Automation"

Nearby in the registry

The prefixes assigned immediately before and after EC:E5:55:

FAQ

Which company owns MAC address prefix EC:E5:55?: MAC address prefix EC:E5:55 is registered to Hirschmann Automation in the IEEE Organizationally Unique Identifier (OUI) registry. Any device whose MAC address begins with EC:E5:55 has a network interface built by Hirschmann Automation.
What is the OUI EC:E5:55?: EC:E5:55 is an Organizationally Unique Identifier — the first three octets (24 bits) of a MAC address, assigned by the IEEE to Hirschmann Automation. It covers every address from EC:E5:55:00:00:00 to EC:E5:55:FF:FF:FF, or 16,777,216 addresses in total. It is also written EC-E5-55.
How do I find the manufacturer of a MAC address?: Take the first three octets of the address — in EC:E5:55:00:00:00 that is EC:E5:55 — 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 Hirschmann Automation located?: Hirschmann Automation is listed at Stuttgarter Straße 45-51 Neckartenzlingen Baden-Württemberg DE 72654 in the IEEE OUI registry entry for EC:E5:55. This is the address the organization registered with the IEEE, which may differ from its current operating address.