We are looking to route all mail to one particular domain through a vpn tunnel and not out to the internet with all other mail. Basically we have two sites (two separate domains) but we are connected by a vpn tunnel. We are both running exchange 2010 and would like email that is sent to each others site to go over the vpn tunnel. What is the best way to achieve our results? Send Connector? Redirect via spam filter or firewall? Any help is greatly appreciated.