Getting a dos machine on the network, and getting dosbox to talk it it

I was trying to play multiplayer doom, and not chocolate doom, where one of the machines is a dosbox and the other is a computer I built after a few months of collecting parts from recycling places. The specs:

For two player doom I simply used a null modem cable and passed it in through to dosbox. But for 3 or 4 players I need a network card.

Getting old DOS machines on the network

I found an ancient unmarked network card, and I could see the chip itself was a Digital 21041-AA DC1017BA.

After a little searching I found two drivers, one was a dos packet driver, and the other was a ndis driver. I plan to use windows for workgroups as well as native dos applications, so I decided to use the ndis driver and use the dis_pkt9.dos shim to get netwokring working.

After transferring the files, I started windows 3.11, and followed the procedure described in the zip file from which I got the dis_pkt9.dos shim. Search around, you'll want the one describing win3.11 compatibility

TAP VPN for online fun

On some machine on my network, I setup a simple openvpn server without any authentication:

cat /etc/openvpn/tap.conf 
port 9988
proto udp
dev tap0

status tap.log
verb 3
# END

And I connected to this from a client (obviously over a more secure VPN), to get a tap0 device on that client.

After I got that device, I could spawn a dosbox directly onto the network interface. You will of course need a version of dosbox patched with NE2000 support (search around for a few builds)

Key parts of the dosbox config for me:

[ne2000]
ne2000=true
nicbase=300
nicirq=9
macaddr=AC:DE:48:88:99:AA
realnic=tap0

I found a generic ne2000.com driver for dosbox, TSR'ed it, then IPXPD.COM (easy to find somewhere), and finally doom's ipxsetup for some doom fun.

OH YEAAAAH the lag