Re: [GnomeMeeting-list] developing plans

[maHo <lukasz mach com pl>]

Damien Sandras wrote:

> Le vendredi 20 août 2004 à 13:35 +0200, maHo a écrit :
>  
>
> >    it's headache. I couldn't talk with lot of my friends because of 
> > that (they had no ability, or knowledge to configure their NAT).
> >
> >    
>
> I understand it is a concern and the reason why most newbies are using
> Skype.
>  

   I think it isn't related to newbie. For example my friend has ISP 
which connect hundreds users through one IP. It's impossible to 
negotiate with ISP to redirect ports to particular user.   

>  
>
> >    hmm, I don't understand you correctly. I think if both parties are 
> > behind NAT, there is no way to establish a call withoud intermediate 
> > server.
> >
> >    
>
> Yes and no...
>
> The problem is to open an association at the NAT-level between the local
> port and the router port, without that association open, no
> communication is possible because the packets will be rejected by the
> router when they arrive. An association is only possible when the host
> behind the NAT has sent a packet to the remote host. If the remote host
> is behind NAT, that packet won't arrive to it, that's the problem.
>
> However, perhaps a public STUN server (a third-server) could be used to
> determine what port is used, pass that port to the other GnomeMeeting
> and then the other GnomeMeeting would guess what port is used on the NAT
> for his calls, most NAT stacks allocating NAT ports in a linear way.
>
> Anyway, in CVS, we have STUN support, but STUN support only works when
> the NAT is not symmetric NAT (read the RFC for more info).
>  

hmm, I don't know if I have enough knowledge to help in that. I'll read 
RFC and try if I can.
Anyway, if there is NATed<->PublicIP model implemented in CVS, it should 
be enough for me

but question: is that NAT stuff Gnomemeeting specific, or there are some 
other clients which should be compatible with that?. Especially - is 
there some client for windows (unfortunately - win95) if I have public 
address, and my fried has windows behind the NAT?

regards

maHo