Network interfaces enable an RRAS server to communicate with other computers over private or public networks. The physical hardware, such as a network adapter, and the network interface configuration are of particular interest when configuring RRAS.

In RRAS, network interfaces are categorized as follows:

• Private interface. A private interface is a network adapter that is physically connected to a private network. Most private networks are configured with a private network IP address range, and the private interface is also configured with a private address. Because a private network is, in theory, composed of known users and computers, you generally have fewer security considerations for a private interface than for a public interface.
  
  
• Public interface. A public interface is a network adapter that is physically connected to a public network, such as the Internet. The public interface is configured with a public IP address. You can configure a public interface to perform network address translation (NAT). Because a public interface is theoretically accessible to anyone on the public network, security considerations are generally higher for a public interface than for a private interface.
  
  
• Demand-dial interface. Demand-dial interfaces connect specified routers on either public or private networks. A demand-dial interface can be either on-demand (activated only when needed) or persistent (always connected).
  
  

When you select Network Interfaces, the details pane displays the currently detected and installed interfaces.

• The RRAS server detects physical network adapters automatically when you run the RRAS Setup Wizard. If you install an additional network adapter after the wizard has been run, you can add and configure the interface using the RRAS MMC snap-in.
  
  
• To create a new demand-dial interface, right-click Network Interfaces, click New Demand-dial Interface, and then follow the steps in the Demand-Dial Interface Wizard.
  
  

Interfaces for physical network adapters cannot be configured in this window.

To configure a demand-dial interface, right-click the interface, click Properties, and then configure the settings on the Demand-Dial Properties page.

You can also configure packet filters for demand-dial interfaces. Right-click the interface, and then click either Set IP Demand-dial Filters or Set IPv6 Demand-dial Filters.

Additional references