[Telepathy] empathy broken during Debian freeze

[Simon McVittie]

On 30/03/13 09:23, Daniel Pocock wrote:
> It suggests that empathy gets TURN servers from Google. 

(To be clear here: "peer" means the person you're calling or the person
who called you.)

If you're using a Google account, telepathy-gabble will obtain a
temporary username/password for Google's TURN server and offer them to
the peer. If you and the peer can't communicate directly (even with
STUN), and the peer also supports TURN, you'll use TURN.

If you're not using a Google account but the peer is, they'll obtain a
temporary username/password for Google's TURN server and offer them to
you. Again, if you and the peer can't communicate directly (even with
STUN), you'll use TURN.

> I can't find
> anywhere to configure my TURN server manually.

No, I think that's a missing feature in telepathy-gabble. The TURN
server itself is the easy bit, really: the non-trivial part is getting
the necessary credentials to use it, either by obtaining a temporary
username/password per call via your XMPP server (similar to the
non-standard API offered by Google servers - I am not aware of any
standard equivalent), or prompting for a (username and?) password with a
SASLAuthentication channel.

> It would be a big
> surprise for many Debian users to find that all their media streams are
> silently routed via a Google TURN server.

This shouldn't happen unless both of these are true:

* no other form of connectivity worked
* either you or the peer are using a Google account (in which case
  Google is technically able to eavesdrop on your traffic anyway)

On a reasonably non-hostile network (e.g. typical home or small office
NAT), STUN should usually be enough to get a call through. The STUN
server is configurable, and STUN is sufficiently low-bandwidth to not
need any special credentials or provisioning (Collabora provides a STUN
server, stun.telepathy.im, which is the default for Telepathy).

    S