Managed VPNUser Guide 177• You must know if the IP address assigned to your Edge’sexternal interface is static or dynamic. To learn about IPaddresses, see Chapter 2, “Installing the Firebox X Edge.”• Your Edge model tells you the number of VPN tunnels that youcan create on your Edge. You can purchase a model upgrade foryour Edge to make more VPN tunnels, as described in “Enablingthe Model Upgrade Option” on page 56.• If you connect two Microsoft Windows NT networks, they mustbe in the same Microsoft Windows domain, or they must betrusted domains. This is a Microsoft Networking problem, andnot a limit of the Firebox X Edge.• If you want to use the DNS and WINS servers from the networkon the other side of the VPN tunnel, you must know the IPaddresses of these servers.The Edge can give WINS and DNS IP addresses to the computers on itstrusted network if those computers get their IP addresses from the Edgeusing DHCP. If you want to give the computers IP addresses of WINS andDNS servers on the other side of the VPN, you can type those addressesinto the DHCP settings in the trusted network setup. For information onhow to configure the Edge to give DHCP addresses, see “Using DHCP onthe trusted network” on page 68.• You must know the network address of the private (trusted)networks behind your Firebox X Edge and of the networkbehind the other VPN device, and their subnet masks.N OTEN OTEThe private IP addresses of the computers behind your Firebox XEdge cannot be the same as the IP addresses of the computers onthe other side of the VPN tunnel. If your trusted network uses thesame IP addresses as the office to which it will create a VPNtunnel, then your network or the other network must changetheir IP address arrangement to prevent IP address conflicts.Managed VPNYou can configure a VPN tunnel on the Firebox® X Edge with twoprocedures: Managed VPN and Manual VPN. For information oncreating a Manual VPN, see “Manual VPN: Setting Up Manual VPNTunnels” on page 178.
