In telecommunications networking, a residential gateway allows the connection of a local area network (LAN) to a wide area network (WAN). The WAN can be a larger computer network (such as a municipal WAN that provides connectivity to the residences within the municipality), or the Internet. WAN connectivity may be provided through DSL, cable modem, a broadband mobile phone network, or other connections.
The term "residential gateway" was originally used to distinguish the inexpensive networking devices designated for use in the home from similar devices used in corporate LAN environments (which generally offered a greater array of capabilities). In recent years, however, the less expensive "residential gateways" have gained many of the capabilities of corporate gateways and the distinctions are fewer. Many home LANs now are able to provide most of the functions of small corporate LANs.
Since the early 2000s the residential or home gateway has been used by Telecommunications Multiple Service Operators [MSOs] as a termination device for connecting consumer premises to a broadband delivery network. As a part of the carrier network, the home gateway supports remote control, detection and configuration.
One of the world’s first residential gateway devices was developed for Italian telecommunications service provider Fastweb in 2001 as part of the launch of the first commercial triple play service. Using its fiber network, Fastweb delivered voice, video and data services to a home gateway device – the first with embedded fiber termination – and enabled them to be distributed around the home via set-top boxes and routers.
Multiple devices have been described as "residential gateways":
- Cable modem
- DSL modem
- Wireless router
- Network switch
- Voice over internet protocol (VoIP) Analog telephony adapter
- Wireless access point
- Wired router
or certain combinations of the above.
A modem (e.g. DSL modem, Cable modem) by itself provides none of the functions of a router. It merely allows ATM or Ethernet or PPP traffic to be transmitted across telephone lines, cable wires, optical fibers, or wireless radio frequencies. On the receiving end is another modem that re-converts the transmission format back into digital data packets.
This allows network bridging using telephone, cable, optical, and radio connection methods. The modem also provides handshake protocols, so that the devices on each end of the connection are able to recognize each other. However, a modem generally provides few other network functions.
- A USB modem plugs into a single PC and allows a connection of that single PC to a WAN. If properly configured, the PC can also function as the router for a home LAN.
- An internal modem can be installed on a single PC (e.g. on a PCI card), also allowing that single PC to connect to a WAN. Again, the PC can be configured to function as a router for a home LAN.
A wireless access point can function in a similar fashion to a modem. It can allow a direct connection from a home LAN to a WAN, if a wireless router or access point is present on the WAN as well.
However, many modems now incorporate the features mentioned below and thus are appropriately described as residential gateways.
A router usually provides:
- Configuration via a web interface
- Dynamic DNS
- Internet protocol routing
- Network address translation (NAT)
- DHCP functions
- firewall functions
- LAN connectivity like a network switch
Most routers are self-contained components, using internally stored firmware. They are generally OS-independent (i.e. can be used with any operating system).
Wireless routers perform the same functions as a router, but also allow connectivity for wireless devices with the LAN, or between the wireless router and another wireless router. (The wireless router-wireless router connection can be within the LAN or can be between the LAN and a WAN.)
Low-cost production and requirement for user friendliness makes the home routers vulnerable to network attacks, which in the past resulted in large clusters of such devices being taken over and used to launch DDoS attacks. Majority of the vulnerabilities were present in the web administration consoles of the routers, allowing unauthorised control either via default passwords, vendor backdoors or web vulnerabilities.