IPv6 has extension options (if that is what you are asking) by using additional headers if required. Also, forward-compatible address extension is something wh

IPv6 has extension options (if that is what you are asking) by using additional headers if required. Also, forward-compatible address extension is something which is simply not possible with routing protocols in place today, and i highly doubt it will be a possibility in the near or far future considering the enroumous coordination effort required between Core players on the Default-free zone and internet at large.