[Standards] LAST CALL: XEP-0368 (SRV records for XMPP over TLS)

Daurnimator quae at daurnimator.com
Mon Jan 30 05:43:52 UTC 2017

On 29 January 2017 at 04:26, XMPP Extensions Editor <editor at xmpp.org> wrote:
> This message constitutes notice of a Last Call for comments on XEP-0368 (SRV records for XMPP over TLS).
> Abstract: This specification defines a procedure to look up xmpps-client/xmpps-server SRV records (for TLS connections) in addition to xmpp-client/xmpp-server and mix weights/priorities.
> URL: http://xmpp.org/extensions/xep-0368.html
> This Last Call begins today and shall end at the close of business on 2017-02-11.
> Please consider the following questions during this Last Call and send your feedback to the standards at xmpp.org discussion list:
> 1. Is this specification needed to fill gaps in the XMPP protocol stack or to clarify an existing protocol?
Ehhh... I haven't personally ever had the requirement for it, and I
think <starttls> is cleaner.

> 2. Does the specification solve the problem stated in the introduction and requirements?

> 3. Do you plan to implement this specification in your code? If not, why not?
I guess? it's quite simple to add support, so might as well...

> 4. Do you have any security concerns related to this specification?

> 5. Is the specification accurate and clearly written?


The stuff in 'requirements' are not requirements but implementation instructions

> When ALPN is used protocol MUST be 'xmpp-client' where 'xmpps-client' is the SRV 'service'.
> When ALPN is used protocol MUST be 'xmpp-server' where 'xmpps-server' is the SRV 'service'.

The phrase "is the SRV 'service'" seems confusing to me.

> TLS provides AT LEAST the same level of security as STARTTLS, and more privacy without ALPN as using STARTTLS leaks that the underlying protocol is XMPP, while any TLS stream should be indistinguishable from any other TLS stream. TLS provides more security than STARTTLS if RFC 7590 [4]

This sentence is confusing and potentially misleading.

> Your feedback is appreciated!

I think it should be noted how devices are expected to connect.
e.g. should they do a SRV request for xmpps-client, and if that
doesn't exist: try xmpp-client; and if that doesn't exist: use an AAAA
record. if that doesn't exist, use an A record?
==> can/should these dns requests be done in parallel? (perhaps see
RFC 6555 Happy Eyeballs)
It should cover desired behaviour if there is a xmpps-* record but no
xmpp-* record

More information about the Standards mailing list