Question 1

What is a MAC address?

Accepted Answer

A MAC (Media Access Control) address is a unique 48-bit identifier assigned to network interfaces. It consists of 6 bytes (12 hexadecimal digits) and is used for communication within a network segment. MAC addresses are assigned by the IEEE and the first 3 bytes identify the manufacturer.

Question 2

What's the difference between unicast and multicast MAC addresses?

Accepted Answer

Unicast MAC addresses are used for individual network interfaces and have the least significant bit of the first byte set to 0. Multicast MAC addresses are used for group communication and have this bit set to 1. Most network interfaces use unicast addresses.

Question 3

What are OUI prefixes?

Accepted Answer

OUI (Organizationally Unique Identifier) is the first 3 bytes of a MAC address assigned by IEEE to manufacturers. For example, Apple devices often start with AC:DE:48, while Intel network cards might start with 00:1B:21. This helps identify the manufacturer of a network device.

Question 4

Can I use these MAC addresses in production?

Accepted Answer

These are randomly generated addresses for testing and educational purposes. For production use in virtual environments, ensure they don't conflict with existing devices on your network. Many virtualization platforms have their own MAC address ranges to avoid conflicts.

Question 5

What do locally and universally administered addresses mean?

Accepted Answer

Universally administered addresses are assigned by the IEEE and guaranteed to be globally unique. Locally administered addresses are assigned by network administrators and only need to be unique within the local network segment. The second least significant bit of the first byte indicates this.

Question 6

Which format should I use?

Accepted Answer

Colon format (00:11:22:33:44:55) is most common on Linux/Unix systems. Dash format (00-11-22-33-44-55) is common on Windows. Dot format (0011.2233.4455) is used by Cisco equipment. Choose based on your target system or personal preference.

Random MAC Address Generator

Generated MAC Addresses

Random Generator

Popular Generators

Other