Home networks are utilized to connect devices in the home to one another and to the Internet. These home networks are connected to residential Internet service providers via a device known as a Residential Gateway (RGW). This device provides physical and protocol connectivity between the home network and the access network (i.e., the core network of the Internet service provider including the Internet service provider's access control devices such as a Broadband Remote Access Server (BRAS) router or Broadband Network Gateway (BNG)).
The RGW can provide bridging or routing support for the home network. It typically also provides additional services such as firewall protection and network address translation. The RGW can connect with the devices in the home using both wired and wireless protocols and connections. The RGW can provide a set of Ethernet connections as well as a wireless local area network using IEEE 802.11(a/b/g/n). The RGW can also be a point of service delivery for services such as Voice Over Internet Protocol (VOIP) or de-multiplexing for services like shared television delivery.
In some situations a home network can have more than one router attached. These additional routers form a hierarchy or tree with the RGW forming the base or root. While the preferred architecture is to avoid such routers, it is helpful for Internet service providers to have visibility for devices within such home network topologies when they are used. However, the addresses of devices connected to routers in these topologies is hidden due to the routers closest to the devices configuring the IP address for the device instead of the RGW.