Would that work?

[raafat]

Hello there!, may you tell us what has led you to this situation ?


Thanks.

[J1mbo]

In this case you could implement (one) layer-2 bridge between the two networks (I would suggest, with DHCP filtering applied). User A would then be able to use an IP address (and gateway) from site-B and vice-versa.

[thisjun]

I think User-A and User-B should setup a proxy server and each browser use opposing proxy.