PMTU Discovery support

[Tom Judge]

aditya kiran wrote:
> Hi,
> I'm just trying to understand the PMTU Discovery support
> in FreeBSD. Is upward PMTU (increase in PMTU) is also
> discovered when PMTU Discovery is enabled?
> Thanks,
> Aditya

As I understand it, it is not possible to detect upward changes in the 
path MTU as there is no mechanism for a router to generate an error when 
a packet is small enough to be accommodated by the MTU of the link to 
the next hop.  I may be wrong though.

Tom