>> It's unlikely that under DOS or Windows that the two IP stacks would
>> know anything about each other. Even on OS/2; I've seen an OS/2 box
>> used as an applications gateway between two networks runing IBM's
>> TCP/IP on one interface and FTP, Inc.'s on the other, and there's
>> absolutely no (direct) interconnection possible between the networks
>> (as I'm told by those involved in the work.) The only way to get from
>> one network to the other would be to telnet into the OS/2 system and
>> then run the OS/2 telnet, e.g., that came with the TCP/IP stack that's
>> running on the remote interface.
>I agree with you on DOS and Windows, but watch out for OS/2. If you run
>IBM's TCP/IP stack over more than one interface, IP forwarding is turned
>on by default. I've seen this with two network cards; we use a dual-homed
>OS/2 PC as a poor man's router (don't ask why). I haven't tried it with
>SLIP or PPP but I'd be careful.
Yes. The trick here is to use two independent TCP/IP stacks from two
different vendors and give each of them only one of the network
interfaces. They don't know about each other, and they don't know
about the other interface.