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LeoTer

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How to select "default" network interface in WIN2K

My computer at home has 2 TCP/IP enabled network interfaces: the physical LAN, and the WAN, which is actually a PPPoE adapter running over the LAN.
All of this works fine, except when I try to run the Net2phone (actually ICQphone) client to make a PC-to-PC call over the internet. A packet sniffer reveals that, during the negotitation of the VoIP connection, Net2Phone sends my internal IP adress (10.0.0.1) to my correspondent's PC, which consequently sends its datagrams into the void. The net result is that, despite the fact that my correspondent is able to hear me, I hear nothing.
When I create a Winsock control and query its LocalIP attribute, it also returns the internal IP address.

So, basically, my question boils down to this: how can I choose TCP/IP or winsock (don't know exactly at which layer the problem occurs) to default to the external interface and ditto IP address, instead of the internal one? Or have I been to zealous at disabling services like RASman?

Any effort to shed light on this problem will be greatly appreciated.
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cooledit
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Hi, LeoTer

Since you have 2 NIC interface's I asume that you then have 2 subnet's

10.x.x.x.x
192.168.x.x

If you are running a Win OS you could then do a Add route 10.x.x.x subnet 255.0.0.0 over there default gateway 10.x.x.x
then tryout a c:\ route print....

Hope this give a clue
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Frabble
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hmm

If you create this static route all communication between the IP address 10.x.x.x. goes over interface 1.
All TCP/IP Connections with the 192.168.x.x goes over interface 2
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LeoTer

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Cooledit: my routing table is correct. Moreover, the outgoing packets do get send to the correct interface, only *inside* the packets, net2phone gives through the IP address of the *wrong* interface.

Frabble: Please give me a few days to take a look at X-lite.

In the meanwhile, other suggestions are still welcome.
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ASKER

OK guys, seems like I forgot to do my homework. The answer I was looking for was right there under my nose. There's a saying for this, only I can't remember it right now.
https://www.experts-exchange.com/questions/21172784/Application-Chooses-Wrong-IP-as-default-IP.html

I'm very sorry to have wasted your time.

PS. I'm willing to reward Frabble with a few points for the link to X-lite, but not the full 400. Since my problem is solved the way I wanted it, I'll stick with ICQphone for now, but that X-lite thingy might come useful one day...