This was an April Fool's joke...there is no such RFC.... :o)
Well, in matter of fact there is one. :o)
http://www.ietf.org/rfc/rfc3514.txt
Netfilter has even an implementation for it. ;o) Unfortunately, it doesn't cope with their 'statful inspection'.
http://lists.netfilter.org/pipermail/netfilter-devel/2003-April/010920.html
FreeBSD claim they have one, but I didn't find the code....
http://daily.daemonnews.org/view_story.php3?story_id=3649
Ethereal as well:
http://www.ethereal.com/lists/ethereal-dev/200303/msg00338.html
Anybody volunteer to implement this ? :o)
Regards -- Emmanuel
