I have a weird situation where my company does not allow RPC over HTTP(S) from outside of the company, but I have a satalite site with about 25 users. The main site and the satalite site are connected by a dedicated gigaman they currently have there own DC/GC but are using webmail, and I would like to give them the ability to access mail through the full client. The satalite site and the main site have a firewall between them, but there is not a firewall bewteen the front-end and back-end servers. Should I even use a FE/BE topology for RPC over HTTP(S)? Do i still need to lock down ports in the registry since all of the Exchange servers and DCs are all on the same network segment? Any suggestions or comments?