Re: [GnomeMeeting-list] Video loss when connecting via 2 Linksys routers

["Kenneth R. van Wyk" <ken vanwyk org>]

> Le mar 29/04/2003 à 13:25, Kenneth R. van Wyk a écrit :
> There is something I don't understand here. Are you really forwarding
> TCP 30000 to 30010 + 1720 and UDP 5000 to 5003 to the internal machine
> or just "allowing" them?

I am forwarding all of the above to my desktop system.  (I would be happy
to send the entire list of open ports, if that would help.)  The router
uses NAT, and I do not have IP translation turned on within GnomeMeeting. 
Also, I have already disabled H245 tunneling and fast start, since I
frequently need to talk with MS-Netmeeting systems.

> If Netmeeting works with the same configuration, then it indicates that
> your router natively supports H.323 and in that case you can *not* use
> port forwarding and IP Translation... Port forwarding and IP Translation
> are only needed when the NAT implementation is not able to natively do
> H.323 as explained in the FAQ...
>
> If your router natively supports H.323, you need to disable IP
> translation, disable H245 Tunneling and Fast Start, and only forward
> 1720 (for incoming calls). You do not even need to open any ports except
> 1720.

Hmmm, I did a bit more investigating...  The router/firewall at both ends
of the connection is a Linksys BEFSR41 with the latest firmware from
linksys.com.  All of the info that I've found on the Linksys site in their
"knowledge base" recommends setting the netmeeting host as a "DMZ" host,
but that would entail allowing *all* incoming traffic to those systems. 
As a security professional, that's something that I'd really prefer
avoiding...

However, I did a bit of additional googling and found the following link:
http://www.compusmart.ab.ca/mikes/lvideo7.html#linksys
It talks about using the Linksys UPnP (Universal Plug-n-Play) feature to
forward MSN traffic to a designated host.  I will investigate doing the
same for netmeeting this evening when I am at home again.

Any other Linksys users out on this list?  What port forwarding settings
are you using?

Cheers,

Ken van Wyk