Routing between two different networks for simultaneous internet sharing and LAN connectivity

Hello,

On a Windows 98 SE host on a LAN, I setup and configured ICS to share its
modem connection to the internet with other Windows 95 client workstations.
Also, I installed dhcp_off.inf to disable ICS' own DHCP feature because all
hosts were assigned static IP addresses. I was able to verify that when DHCP
is disabled, ICS will work as long as ICS clients have IP addresses from
class 192.168.0, which is not my case. That is, all my network has been
assigned addresses from class 210.1.1.0 (I didn't do it in the first place
and I'm not allowed to change it to 192.168.0). This wouldn't seem to be a
major problem as it's possible to -easily- add additional IP addresses to
any given network adapter (as per KB's article 156772) on client
workstations. This way, in theory, any given client workstation would
communicate with other peers on the LAN via its, let's say old, IP address
from class 210.1.1.0, and at the same time would route its internet traffic
via its 192.168.0.x address. But this is theory only.
Well, here is the problem:
On any given client workstation, its 192.168.0.x IP address is routed
through gateway 192.168.0.1, which is the address of the ICS host. This fact
allows the workstation to access the internet but doesn't allow it to
communicate with the other hosts on the LAN because, as it can be seen,
*all* ip traffic (included all packets addressed to 210.1.1.x hosts) gets
routed through 192.168.0.1
The fix for this, so that any given Windows 95 client workstation can access
the internet and communicate with other workstations *at the same time*
would be to allow it to route all IP traffic through 192.168.0.1 (this is
the default setup) except traffic addressed to the local network, which
shouldn't be routed through the gateway as it must remain on the same
ethernet segment. I tried some combinations of "route add/change/delete"
commands on client workstations, but wasn't able to fix the issue, I mean,
if client workstations have internet access, they cannot see their peers on
the LAN and viceversa.

Following are the routing tables on the ICS host and on a typical Windows 95
client workstation.

"route print" on the ICS Windows 98 SE host:
(210.1.1.0 is the internal network)

Active routes:
Network Address Netmask Gateway Address Interface
Metric
0.0.0.0 0.0.0.0 200.43.71.93 200.43.71.93 1
127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 1
192.168.0.0 255.255.255.0 192.168.0.1 192.168.0.1 2
192.168.0.1 255.255.255.255 127.0.0.1 127.0.0.1 1
192.168.0.255 255.255.255.255 192.168.0.1 192.168.0.1 1
200.43.71.0 255.255.255.0 200.43.71.93 200.43.71.93 1
200.43.71.93 255.255.255.255 127.0.0.1 127.0.0.1 1
200.43.71.255 255.255.255.255 200.43.71.93 200.43.71.93 1
210.1.1.0 255.255.255.0 210.1.1.8 192.168.0.1 2
210.1.1.8 255.255.255.255 127.0.0.1 127.0.0.1 1
210.1.1.255 255.255.255.255 210.1.1.8 192.168.0.1 1
224.0.0.0 224.0.0.0 200.43.71.93 200.43.71.93 1
224.0.0.0 224.0.0.0 210.1.1.8 192.168.0.1 1
255.255.255.255 255.255.255.255 210.1.1.8 192.168.0.1 1

"route print" on the Windows 95 client:
(192.168.0.1 is the ICS host acting as gateway for internet traffic)

Active routes:
Network Address Netmask Gateway Address Interface
Metric
0.0.0.0 0.0.0.0 192.168.0.1 192.168.0.2 1
63.210.47.33 255.255.255.255 192.168.0.1 192.168.0.2 1
64.4.18.250 255.255.255.255 192.168.0.1 192.168.0.2 1
64.4.33.7 255.255.255.255 192.168.0.1 192.168.0.2 1
65.54.192.248 255.255.255.255 192.168.0.1 192.168.0.2 1
65.54.194.117 255.255.255.255 192.168.0.1 192.168.0.2 1
65.54.211.62 255.255.255.255 192.168.0.1 192.168.0.2 1
65.54.225.254 255.255.255.255 192.168.0.1 192.168.0.2 1
65.54.226.252 255.255.255.255 192.168.0.1 192.168.0.2 1
127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 1
192.168.0.0 255.255.255.0 192.168.0.2 192.168.0.2 1
192.168.0.2 255.255.255.255 127.0.0.1 127.0.0.1 1
192.168.0.255 255.255.255.255 192.168.0.2 192.168.0.2 1
198.5.148.16 255.255.255.255 192.168.0.1 192.168.0.2 1
198.104.151.116 255.255.255.255 192.168.0.1 192.168.0.2 1
207.68.177.124 255.255.255.255 192.168.0.1 192.168.0.2 1
207.68.177.126 255.255.255.255 192.168.0.1 192.168.0.2 1
207.171.183.16 255.255.255.255 192.168.0.1 192.168.0.2 1
216.239.41.104 255.255.255.255 192.168.0.1 192.168.0.2 1
224.0.0.0 224.0.0.0 192.168.0.2 192.168.0.2 1
255.255.255.255 255.255.255.255 192.168.0.2 192.168.0.2 1


I will highly appreciate hints on how I can fix this, if it is possible.
Thank you,

Fernando Ronci
E-mail: (E-Mail Removed)