This is a technical Kata, it requieres some knowledge of network addresses to understand the description.
Although all terms are explained in the description, it's quite brief and may not be enough for some users.

I suggest we link explanations for MAC and IPv6 addresses. If someone is struggeling with the technical nature of
the Kata, they have a good starting point :)

If all hexadecimal characters in the output have to be lowercased,
it should be stated wether we can expect a lowercased input as well :)

then invert the U/L bit, which is the bit 1 of the highest byte of the MAC address.

This part is not clear, should be flip the 7th bit of the first 8bit as refered in the video