Document sharing issues

[Guillaume Desmottes]

Le mardi 22 avril 2008 à 04:26 -0400, Polychronis Ypodimatopoulos a
écrit :
> Guillaume Desmottes wrote:
> > Le lundi 21 avril 2008 à 10:24 -0500, James Simmons a écrit :
> >   
> >> 2).  Downloading a document is very slow.  I distribute View Slides 
> >> files on an Apache server, using the Browse activity to copy same to the 
> >> Journal.  This takes under a minute even for a large file (over 15mb).  
> >> Then I share the document with another instance of Sugar on the same 
> >> box.  *That* is agonizingly slow.  I know the two instances are not 
> >> communicating directly, but it still seems like there is a lot of 
> >> overhead going on.  Can I do anything about this?
> >>     
> >
> > Were you using Gabble or Salut? Currently Gabble stream tubes still send
> > their data through the jabber server making transfer really slow. I'm
> > working on implementing real p2p instead (#4047).
> > Salut doesn't have this problem though as it already uses TCP
> > connections.
> >   
> Can you elaborate more on this? Isn't TCP the underlying mechanism for 
> Gabble also? How is Salut more efficient?

Gabble uses one TCP connection to the jabber server and when you connect
to a stream tube, all the data are send using this connection. This is
very inefficient because all the data are encoded into base64 XML
stanzas and go trough the server (the traffic inside a stream tube can
potentially be really big).
What we need to do is to establish a *new* TCP connection between the 2
peers of the tube. So data won't have to be encoded to base64 and won't
go trough the server anymore. But that's not an easy task as peers can
potentially be behind a NAT. So we have to use NAT traversal magic using
Jingle, ICE and stuffs as we do for audio/video calls.

Salut doesn't have this problem as peers are on the same network and so
can directly talk to each other.


	G.