The physical interfaces of the Branch Gateway router include:

FastEthernet InterfaceThe 10/3 Fast Ethernet port on the front panel of the Branch Gateway provides a FastEthernet interface. This interface is an autosensing 10/100 Mbps Fast Ethernet port. It can be used to connect to a LAN, an external firewall, an external Virtual Private Network (VPN), or a DeMilitarized Zone (DMZ). This interface can also be used as a WAN interface when configured for PPPoE. For more information, see Configuring PPPoE.

Switching Interface An internal 100 Mbps connection to the Branch Gateway internal switch provides a switching interface. The switching interface supports VLANs. By default, the switching interface is associated with the first VLAN (Vlan 1).

When you configure the Branch Gateway without an external VPN or firewall, Vlan 1 is used to connect the internal Branch Gateway router to the internal Branch Gateway switch. If an external firewall or VPN is connected to the Fast Ethernet port, it is important to disable Vlan 1 to prevent a direct flow of packets from the WAN to the LAN.