Re: [Sip] Using TLS in the first hop - Bug in RFC 5630

Iñaki Baz Castillo <ibc@aliax.net> Thu, 15 September 2011 15:25 UTC

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Date: Thu, 15 Sep 2011 17:27:27 +0200
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From: =?UTF-8?Q?I=C3=B1aki_Baz_Castillo?= <ibc@aliax.net>
To: Hadriel Kaplan <HKaplan@acmepacket.com>
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Cc: "<sip@ietf.org>" <sip@ietf.org>, "Olle E. Johansson" <oej@edvina.net>
Subject: Re: [Sip] Using TLS in the first hop - Bug in RFC 5630
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2011/9/15 Hadriel Kaplan <HKaplan@acmepacket.com>om>:
> But that's not the only use-case for Contact - the Contact URI of Alice can be used at any time later for an out-of-dialog request to Alice, and at that point it suddenly needs a full sips path to Alice.  For example in a REFER case.

If Alice wants to refer Bob to Carol, Alice would do better by sending
a REFER with "Refer-To: <sip:carol@domain.org>" rather than using
SIPS. Not sure if you meant this.

Anyhow, what do you mean then? the section 3.1.3 in RFC 5630 is buggy
as I told in my first mail, am I wrong? By setting a Contact with SIP
rather than SIPS, that means that in-dialog requests would be sent to
the caller using UDP/TCP rather than TLS, so they would fail
(assumming that the caller is just reachable using TLS, let's imagine
NAT and so).

-- 
Iñaki Baz Castillo
<ibc@aliax.net>