VPN Clients and Quarantined Clients network properties
Whenever a remote access VPN client connects to the Microsoft Forefront Threat Management Gateway firewall, then the IP address assigned to the VPN client is automatically added to the dynamic VPN Clients network. If you use DHCP to assign IP addresses to VPN clients, those addresses will be automatically added to the VPN Clients network when a VPN client connects and is assigned an address on that network.
Dynamically assigned IP addresses of VPN clients who are currently in VPN quarantine are automatically assigned to the Quarantined VPN Clients network.
Neither of these networks can be modified.