On Thu, Apr 23, 2015 at 8:57 PM, Watson Ladd <[email protected]> wrote:

>
> On Apr 23, 2015 1:52 PM, "Phillip Hallam-Baker" <[email protected]>
> wrote:
> >
> > On Thu, Apr 23, 2015 at 4:21 PM, [image: ๐Ÿ”“]Dan Wing <[email protected]>
> wrote:
> >
> > > I am not an expert on DTLS but that was the concern that made me avoid
> using
> > > it. I want a completely stateless resolver, not just UDP.
> > >
> > > That means using either a very fast ECC scheme for authentication or
> some
> > > sort of kerberos ticket.
> > >
> > >
> > > I believe "Transport Layer Security (TLS) Session Resumption without
> > > Server-Side State", https://tools.ietf.org/html/rfc5077 solves that
> problem.
> > > It works with TLS and with DTLS.
> >
> > That is an option in DTLS.
> >
> > For a DTLS based scheme to be acceptable, client support has to be
> mandatory.
> >
> > If we do that, I have no problem with the additional overhead.
> >
> >
> > The question then is whether we can profile DTLS without in effect
> > requiring a new implementation library.
>
> This doesn't solve the actual problem, as compared with DNS/UDP.
>
> DTLS resumption requires a round trip: the server keeps that state alive
> as a new DTLS connection, and then the client or server closes it after
> using it. So if you have 10,000 clients, even if only 100 of them issue
> queries a second, but over two minutes they all do, you will either force
> them all to pay the latency price of reopening the connection or store
> state for 10,000 DTLS sessions.
>
> Another problem is with anycast. Ordinarily failover is completely
> transparent to users: the packets go somewhere else, and get responded to.
> I don't see how this works with TLS, unless you do fancy stateful failover
> tricks.
>
> The easiest solution is to encrypt packets with a public key that the
> servers have, or force every packet to contain something equivalent to
> resumption data. But that requires not using TLS/DTLS.
>
> Sincerely,
> Watson Ladd
>

Ah, then it doesn't work.

I can't see why people are so insistent on clinging to a familiar label. Is
it because it is easier to put blind faith in TLS than consider how it
works?
_______________________________________________
dns-privacy mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/dns-privacy

Reply via email to