After some private email from Scott: The registry also assigns 7 to TP/IX, which became CATNIP. So 7 also needs to be changed to Reserved and RFC1707 and RFC1475 both need to become Historic. http://www.iana.org/assignments/version-numbers/version-numbers.xhtml#version-numbers-1 Brian On 18/03/2016 09:13, Brian E Carpenter wrote: > If we are doing this, then I think that CATNIP (RFC1707) needs to be made > Historic at the same time, even though it didn't need an IP version number. > > I also recall rumours that some people were actually using ST2 at one point. > Are we sure that it's totally gone away? > > Regards > Brian Carpenter > > On 18/03/2016 08:15, The IESG wrote: >> >> The IESG has received a request from the Internet Engineering Steering >> Group IETF (iesg) to consider the following document: >> - 'Moving IP versions 5, 8, and 9 to Historic' >> <status-change-ip-versions-5-8-9-to-historic-01.txt> as Historic >> >> The IESG plans to make a decision in the next few weeks, and solicits >> final comments on this action. Please send substantive comments to the >> ietf@xxxxxxxx mailing lists by 2016-04-14. Exceptionally, comments may be >> sent to iesg@xxxxxxxx instead. In either case, please retain the >> beginning of the Subject line to allow automated sorting. >> >> The file can be obtained via >> https://datatracker.ietf.org/doc/status-change-ip-versions-5-8-9-to-historic/ >> >> IESG discussion can be tracked via >> https://datatracker.ietf.org/doc/status-change-ip-versions-5-8-9-to-historic/ballot/ >> >> >> No IPR declarations have been submitted directly on this I-D. >> >> >>