On Thu, Aug 28, 2008 at 08:31:25AM -0700, Nicholas Weaver wrote:
> Do people know of any stub resolvers which cache beyond the direct
> answer when asking a recursive resolver?

Very little is known (at least, here) about the behaviour of the many
different stub resolvers.

Some applications (browsers) bring their own dedicated stub resolver, in
other cases the "stub resolver" is actually a repeater in a domestic router
or modem.

I suspect Microsoft Exchange to also have a built-in stub given its
unorthodox DNS behaviour at times.

This next to the stubs in phones, and the zoo of operating system versions.

More study might be in order.

> EG, if the recursive resolver when asked "www.foo.com", also returns
> an additional record "advertisements.foo.com A", will any
> known stub resolvers cache that additional value?

I expect this behaviour to be very rare. CNAME chain following is about
where most stub resolvers end, in my expectaction.


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