These network cards usually come with a bootable CD-ROM that executes a utility that permits the user to change the MAC address burned into the EEPROM. Other methods of changing the MAC address are permanent at least one network card manufacturer bundles networking hardware with software that allows the user to change the MAC address. Changing the MAC address in this way is not permanent: after a reboot, it will revert to the MAC address physically stored in the card. Similarly, some software licenses are bound to a specific MAC address. Changing the MAC address of the new interface will solve the problem. Some Internet service providers bind their service to a specific MAC address if the user then changes their network card or intends to install a router, the service won't work anymore. This can be useful for privacy reasons, for instance when connecting to a Wi-Fi hotspot, or to ensure interoperability. Although physical MAC addresses are permanent by design, several mechanisms allow modification, or 'spoofing', of the MAC address that is reported by the operating system.

Mac address changer mac os