I have a firewall with 3 interfaces, WAN, DMZ and LAN. Currently I have a OWA server in the DMZ talking to the Exchange server on the LAN. Everything is open between the DMZ and the LAN. I want to tighten up the security between the DMZ and the LAN. What traffic absolutely needs to pass? I know the domain traffic needs to pass, and the stuff for Exchange. What ports are these and how should it be done?
Thanks
Thanks