MAC address vendor (OUI) nachschlagen
Der erste 3 Bytes von ein MAC address (OUI) identifizieren der manufacturer. Look up vendors für network device identification und inventory.
- 1
A MAC address is 6 bytes (48 bits). The first 3 bytes are the Organizationally Unique Identifier (OUI) assigned by the IEEE to a manufacturer. The last 3 bytes are device-specific. Looking up the OUI identifies the vendor — useful for network inventory, troubleshooting, and device identification.
- 2 MAC-Adress-Tool →
Enter a MAC address (e.g., 00:1B:44:11:3A:B5) to look up the manufacturer from the OUI database. The tool formats the address and queries the IEEE OUI registry. Common formats: 00:1B:44:11:3A:B5, 00-1B-44-11-3A-B5, 001B44113AB5.
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OUI lookup is useful for: identifying unknown devices on your network, inventory management, troubleshooting (knowing the vendor narrows down the device type), and security (detecting spoofed MACs — if a "Cisco" OUI appears on a consumer device, it may be spoofed). The IEEE updates the OUI database regularly.
Häufige Fragen
- Can MAC addresses be spoofed?
- Yes. MAC addresses can be changed in software on most network interfaces. This is used legitimately for privacy (random MACs in modern mobile OS) and testing, but also for bypassing MAC filters and impersonating devices. Do not rely on MAC addresses for security.
- What is a locally administered MAC?
- The second-least-significant bit of the first byte indicates whether the MAC is globally unique (0, assigned by IEEE) or locally administered (1, set by the user). Locally administered MACs are used for VMs, containers, and privacy (random MACs). Example: x2:xx:xx:xx:xx:xx or x6:xx:xx:xx:xx:xx.