On 25/04/2017 19:26, Joe Touch wrote:
Hi, Stewart,
On 4/24/2017 10:12 AM, Stewart Bryant wrote:
Minor issues:
A node MUST NOT reduce its estimate of the Path MTU below the IPv6
minimum link MTU.
SB> I missed this last time.
SB>
SB> Presumably you mean "A node MUST NOT reduce its estimate of the
SB> Path MTU below the IPv6 minimum link MTU in response to such
SB> a message."
This seems fine to me, FWIW - i.e., limiting the advice in this doc to
the mechanism in this doc.
SB>
SB> Otherwise I would have thought that this was entirely a matter
SB> for the host whether it wanted to use a Path MTU below the IPv6
SB> link minimum. Nothing breaks if the host takes a more conservative
SB> decision.
I don't agree; the host at that point is violating RFC2460. It should
never think that an IPv6 link or path with an MTU below what RFC2460
requires is valid.
Joe
That is as maybe, but a host can do more or less what it wants, so this
is surely an
unenforceable constraint, or are you telling me that the receiving host
MUST drop a
fragment that is shorter than this? In which case the question whether
in practice
they do, and whether such a constraint is reasonable.
- Stewart