[Telepathy] P2P tubes on link-local (Salut)

[Alban Crequy]

Hi,

Salut implements MUC tubes, but not 1-1 tubes:
http://telepathy.freedesktop.org/wiki/Tubes

Our current "tubes over XMPP" spec does not specify 1-1 tubes on
link-local:
http://telepathy.freedesktop.org/xmpp/tubes.html

I started a draft to add 1-1 tubes on link-local (both stream tubes
and D-Bus tubes) on this spec:
http://monkey.collabora.co.uk/telepathy-gabble-alban-tube/
HTML version: http://people.collabora.co.uk/~alban/tmp/tubes.html

Some points:

- We don't need NAT traversal on link-local, a direct TCP connection
  should be enough for both D-Bus and stream tube.

- I use the Jingle namespace, but I don't know if it is correct:
  <transport xmlns='urn:xmpp:tmp:jingle:transports:raw-tcp'>

- <message> stanzas are avoided to advertise and establish a tube: <iq>
  is more relevant for things that look like method calls and method
  returns, and we avoid this bug:
  https://bugs.freedesktop.org/show_bug.cgi?id=14485

- No <presence> stanza is added.

- Other tubes is not changed (1-1 XMPP, MUC XMPP and MUC link-local)
  to remain compatible with current implementations.

Comments welcome.

-- 
Alban