how to convert mac address to an ipv6 interface id

This way we get 64-bit host portion of the IPv6 address. I will use the colon (:) as the delimiter and blocks of 2-bytes to make it compliant with the IPv6 convention. Use the MAC address after modifying the 7th bit in step 1 and inject the FFFE between OUI (first three bytes on the left) and the serial number of the adapter (first three bytes on the right). This gives us the hexadecimal value of: CE. This one must be flipped like shown below:ġ10011 10. 3):Ĭounting from left to right the 7th bit is: 110011 00. MAC address used in the example is (as per pic. In order to do that, operating system must first convert the hexadecimal number of the first byte to the binary form. Here is the detailed description of how 48 bits of MAC address becomes 64 bit host portion of IPv6 address in EUI-64 method (operating system takes care of these details itself).įlip the 7th bit (counting from left to right) in the MAC address (if it's 1 change it to 0, if it's 0, change it to 1).

And the same method can be used to assign the host bits in the global address. In the EUI-64 method the operating system takes the MAC address (highlighted) and uses it to create the host bits for the link-local address by default (you can also do this manually).

How to convert mac address to an ipv6 interface id