Re: [Stox] Stephen Farrell's IESG feedback on draft-ietf-stox-core

Peter Saint-Andre <> Mon, 10 February 2014 22:52 UTC

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Date: Mon, 10 Feb 2014 15:52:11 -0700
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Subject: Re: [Stox] Stephen Farrell's IESG feedback on draft-ietf-stox-core
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On 2/10/14, 3:20 PM, Stephen Farrell wrote:
> Hi Peter,
> On 02/10/2014 06:24 PM, Peter Saint-Andre wrote:
>> ( + STOX WG since one of the issues might deserve broader discussion )
>> Hi Stephen, thanks for your review:
>> You wrote in part:
>>     - I wondered why you didn't just say that (D)TLS SHOULD
>>     be used/supported between gateways. Given that all the
>>     relevant bits of code are likely to support that, wouldn't
>>     it be a good thing?
>> Yes, that seems eminently reasonable.
> Just to be clear - the above is the only DISCUSS point.


>>     - Has anyone thought about confusability in the name
>>     mappings? I expected to see a bit of text in the
>>     security considerations but didn't see it.
>> Confusion is always possible. :-) Were you thinking about confusable
>> characters from Unicode, or something else?
> Right. Maybe its all there already and I just didn't see
> if in the mapping stuff, or maybe not. I'm not sure.

Section 10.5 of draft-ietf-precis-framework has some very nice text 
about visually similar characters. We could borrow from that.

>>     - It seems a shame to not be able to gateway when the To is
>>     a sips URI at all but I understand that some loss of
>>     security is inevitable for cases like this. Is there any
>>     work planned for an update that would allow gatewaying for
>>     such cases, e.g. if the 1st XMPP server is the one to which
>>     the user is connected and the user is connected using
>>     XMPP/TLS?
>> Hmm. I cannot say that I am aware of planning for updates to provide
>> more secure gatewaying, although folks active in the STOX WG might be
>> thinking along those lines.
>> Depending on the deployment architecture, I think there are cases where
>> it is *possible* to TLS-protect all the hops. For instance, if
>> has a direct server-to-server connection to
>> (no intermediate hops) and both organizations agree to
>> force the use of TLS for client connections (e.g., via SLA), then I
>> suppose that could honor 'sips' URIs when sending
>> traffic to However, such an arrangement is rare enough
>> right now that I don't know if it is worth mentioning.
> Fair enough. I can see that detecting that you (probably) have
> all (D)TLS hops might be tricky and error prone.

That's how I see it.

Oh, and we at least need to mention DTLS for the UDP cases, though (see 
Section 5 of draft-ietf-stox-core).


Peter Saint-Andre