Test your connectivity for World IPv6 Day

Rémi Després remi.despres at free.fr
Mon Jun 6 22:26:20 CEST 2011

Le 6 juin 2011 à 18:55, Fred Baker a écrit :

> On Jun 6, 2011, at 8:58 AM, Rémi Després wrote:
>> Unless there are good reasons to know that a longer PMTU applies to all their connections, all servers SHOULD send IPv6 packets to off-link destinations with 1280 octets as default PMTU.
>> Servers that don't do that are open for PMTU problems. 
> I understand where you're coming from,


> but I disagree.

Well, if you deny that there are operational problems with PMTUD today, you may be better informed than I am.

> I think servers and the networks supporting them need to implement PMTU. The way to do that is (pick one) RFC 4821 in TCP or to manage to not block ICMPv6.

- At least Packet-too-big ICMPv6 messages should never be blocked, agreed, but for others this isn't AFAIK as obvious. 
- Servers that deliver valuable contents don't control where ICMPv6 may be blocked.


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