Re: WIndows Updates Fail Via IPv6 - Update!

[Mark Tinka <mark.tinka () seacom mu>]

On 3/Mar/19 18:05, Jeroen Massar wrote:

> IPv6 requires a minimum MTU of 1280.
>
> If you cannot transport it, then the transport (the tunnel in this case) needs to handle the fragmentation of packets 
> of 1280 down to whatever does fit in the tunnel.

As you know, IPv6 does not support fragmentation in transit. So that's
not an option.

Host fragmentation is per standard, but signaling of that was not so
successful in IPv4. Real world scenarios for IPv6 (reasonably) apply here.


> Have fun with all your UDP traffic that does not care about your TCP MSS adjustment. You just hid the problem...

I considered this issue, but as with all things UDP re: fragmentation,
it depends.

Testing I've been doing all day shows previously (mostly-TCP) issues
have resolved, and I've not run into any major problems that are
impacting UDP. Nonetheless, I'm keeping an eye out.


> And a correctly configured MTU is especially going to be fun with "HTTP/3" that is being pushed through, even though 
> the predecessor QUIC does not care about MTU at all... good that it is all in the hands of a company that can fix it 
> themselves ;)

Is it an ideal situation? About as ideal as flying in the cargo bay. But
my reality is that until my FTTH provider can deliver native IPv6, this
is what I have.

Mark.