We recommend using a traditional perimeter network for your Enterprise Portal network environment. A traditional perimeter network enhances the security of the Enterprise Portal configuration by using two firewalls and two domain controllers to restrict access to Microsoft Dynamics AX data. For more information, see Configure a traditional perimeter network for Enterprise Portal.
If a traditional perimeter network is not a feasible option for your organization, consider using a standard perimeter network that uses Microsoft ISA Server as your perimeter network's firewall server. You can access the Microsoft Business Solutions Perimeter Network Configuration Wizardon the Web to help you install and configure your standard perimeter network.
If you do not have experience setting up and configuring network security, contact your Microsoft Certified Partner for assistance. If you do not set up the perimeter network correctly, your system might be vulnerable to security threats.