The comment I was responding to asserted that IPv6 as a whole is unfixable which is not true. With regards to fragmentation, I would say "fragmentation in gene

The comment I was responding to asserted that IPv6 as a whole is unfixable which is not true. With regards to fragmentation, I would say "fragmentation in general is unfixable", no matter the protocol. Thankfully with IPv6, the guaranteed minimal packet size is relatively reasonable (1280 bytes), so maybe it's now time to finally go there. v6 already changed the rules with fragmentation a bit in that routers won't have to fragment any more but are allowed to just drop packets smaller than the MTU and sending back an ICMPv6 packet announcing that they have done so. Unfortunately, ICMP is still dropped at many firewalls even though I would argue that it's absolutely essential for IPv6 functionality (when it was more optional in v4). As it stands now, hosts are still allowed to fragment packets themselves (which is what's happening in this article), but the solution is probably to not do that either in the future. DNSSec over UDP is a problem in that regards, but people aren't convinced that DNSSec is the way to go anyways (just ask tptacek here on this site). (edit: with regards to the fragment checking site you pointed me to: In our case, all is well because I do recognise the necessity of ICMPv6 and thus have configured the firewalls accordingly)