Microsoft Forefront Threat Management Gateway networks are created and configured to model your physical corporate networks. Forefront TMG constructs a number of predefined networks during installation, and you can also create custom networks. Typically a network exists for each network adapter installed on the Forefront TMG server. For more information about the predefined networks, see the following topics:
Internal and perimeter network properties
External network properties
Local Host network properties
VPN Clients and Quarantined Clients network properties
Before modifying or creating networks, be sure that you understand how Forefront TMG implements the network model. For more information, see Before creating networks.