chat program behind a router

[Dar Scott]

On Friday, April 5, 2002, at 10:17 AM, Mark Talluto wrote:

> Is my problem with settings on the routing software or with my 
> chat program?  Any insight on this would be greatly appreciated.

My guess is that the router has some sort of firewall capability.  
This can cause problems in a couple ways.  It might not allow TCP 
connections (or UDP packets) from the outside (though most make 
exceptions for FTP).  Second, it might be set up for NAT, static or 
masquerade.  Even if you are set up for masquerade, there may be a 
"server" option that forwards certain connection attempts to the 
router to a particular computer.

If you can't change settings on the router, try creating a server 
stack that runs someplace outside the firewall.  Have all chat 
clients TCP to that.

If you need only point to point, have b TCP to a.

(It is sometimes easier to establish a dialog through a firewall 
with TCP than with UDP.  This is especially the case with with mc 
port assignment limitations; the firewall might only allow a packet 
with exactly the source & destination swapped from one that 
recently went out.)

Hope this helps.

Dar Scott