EDNS and DNSSEC impossible to use in Satellite links

[Aliet Santiesteban Sifontes]

I have been many days working around this, searching and posting in
the list, and after all the tests I'm concluding that edns and dnssec
can not be used in satellite links, at least with bind 9.5.0P2 on rhel
5.2, why I say this:
A round trip time  for a package in a satellite link is ~500 ms, now
depending on traffic, weather and many other factors, this times can
be in the real life ~600 ms ~700 ms, analyzing a capture on our
gateway we can find that timeouts are happening for a query for
responses times of ~601 ms, when the responses arrives the udp socket
in the server it has been closed after this time and this genereates
icmp packages of port unreachable, there is no problem with the size
of the udp packages, or fragments out of order, this is not the
problem in this case, In satellite links those times are a normal
behaviour, so it should be a way to configure bind udp timeouts
values, specially for this cases, not only udp sizes, there are many
people using this kind of links, for example islands, using current
timeouts nobody with this kind of link will use edns and dnssec, I
attached a capture of the gateway so you can see what I mean, see
responses times.
Any ideas, best regards, perhaps a new feature??, a bug??