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A home network or home area network (HAN) is a type of local area network that develops from the need to facilitate communication and interoperability among digital devices present inside or within the close vicinity of a home. Devices capable of participating in this network–smart devices such as network printers and handheld mobile computers–often gain enhanced emergent capabilities through their ability to interact. These additional capabilities can then be used to increase the quality of life inside the home in a variety of ways, such as automation of repetitious tasks, increased personal productivity, enhanced home security, and easier access to entertainment.
One of the primary drivers behind the establishment of this kind of network is the need to distribute residential Internet access to all internet capable devices in the home. Due to the effect of IPv4 address exhaustion, most Internet Service Providers provide only one WAN-facing IP address for each residential subscription. Therefore most homes require a device capable of network address translation (NAT) that can route packets between the public address visible to the WAN and private addresses of individual devices that share that public address. This router defines the boundary at which the service provider's network stops and the home's network begins. While it is possible for home networks to exist without connectivity to the outside world via a router, such topologies would have limited utility considering the bulk of current home network usage comes from home devices communicating with the WAN rather than with other home devices.
A home network usually relies on one of the following equipment to establish physical layer, data link layer, and network layer connectivity both internally amongst devices and externally with outside networks:
Home networks can use either wired or wireless technologies to achieve full connectivity. Home networking may use
One of the most common ways of creating a home network is by using wireless radio signal technology; the 802.11 network as certified by the IEEE. Most products that are wireless-capable operate at a frequency of 2.4 GHz under 802.11b and 802.11g or 5 GHz under 802.11a. Some home networking devices operate in both radio-band signals and fall within the standard 802.11n. Wi-Fi is a marketing and compliance certification for IEEE 802.11 technologies. The WiFi Alliance has tested compliant products certifies them for interoperability.
Low power, close range communication based on IEEE 802.15 standards has a strong presence in homes. Bluetooth continues to be the technology of choice for most wireless accessories such as keyboards, mice, headsets, and game controllers. These connections are often established in a transient, ad-hoc manner and is not often seen as an act of expanding a home network.
A "low-rate" version of the original WPAN protocol was used as the basis of ZigBee. Despite originally being conceived as a standard for low power machine-to-machine communication in industrial environments, the technology has been found to be well suited for integration into embedded "Smart Home" offerings that are expected to run on battery for extended periods of time. ZigBee utilizes mesh networking to overcome the distance limitations associated with traditional WPAN in order to establish a single network of addressable devices spread across the entire building. Z-Wave is a newer standard also built on 802.15.4, that was developed specifically with the needs of home automation device makers in mind.
Most wired network infrastructures found in homes currently utilize some form of category 5 or category 6 twisted pair cabling with RJ45 compatible terminations. This type of medium provides physical connectivity between the Ethernet interfaces present on a large number of residential IP-aware devices.
As an alternative to wireless networking or additional network cable installation, the existing home wiring (coax in North America, telephone wiring in multi dwelling units (MDU) and power-line in Europe and USA) can be used as a network medium. Using these wiring systems requires installation of a home networking device before the network can be accessed by the end user device.
The ITU-T G.hn and IEEE Powerline standard, which provide high-speed (up to 1 Gbit/s) local area networking over existing home wiring, are examples of home networking technology designed specifically for IPTV delivery.  Recently, the IEEE passed proposal P1901 which grounded a standard within the Market for wireline products produced and sold by companies that are part of the HomePlug Alliance. The IEEE is continuously working to push for P1901 to be completely recognized worldwide as the sole standard for all future products that are produced for Home Networking.
The following standards allow devices to communicate over coaxial cables, which are frequently installed to support multiple television sets throughout homes.
Some older devices may not feature the appropriate network interfaces required for home network connectivity. In some situations, USB dongles and PCI Network Interface Cards are available as accessories that enable this functionality.
Due to the lowering cost of computing and the ubiquity of smartphone usage, many traditionally non-networked home equipment categories have begun seeing new variants capable of control or remote monitoring through an app on a smartphone. Newer startups and established home equipment manufacturers alike have begun to offer these products as part of a "Smart" or "Intelligent" or "Connected Home" portfolio. The control and/or monitoring interfaces for these products can be accessed through proprietary smartphone applications specific to that product line.
Instead of selling individual products, some service providers have begun offering complete and externally managed home automation and home security solutions that lease networked systems of devices in a subscription model together with externally managed services.
Most small embedded home network devices require remote configuration from a PC on the same network. For example, broadband modems are often configured through a web browser running on a PC in the same network. These devices usually use a minimal Linux distribution with a lightweight HTTP server running in the background to allow the user to conveniently modify system variables from a GUI rendered in their browser. These pages use HTML forms extensively and make attempts to offer styled, visually appealing views that are also descriptive and easy to use.
For HAN users, Microsoft offers simple access control features built into their Windows Operating System. Homegroup is a feature that allows shared disk access, shared printer access and shared scanner access among all computers and users (typically family members) in a home, in a similar fashion as in a small office workgroup, e.g., by means of distributed peer-to-peer networking (without a central server). Additionally, a home server may be added for increased functionality.
A Windows HomeGroup is a new feature in Microsoft Windows 7 that simplifies file sharing. All users (typically all family members), except guest accounts, may access any shared library on any computer that is connected to the home group. Passwords are not required from the family members during logon. Instead, secure file sharing is possible by means of a temporary password that is used when adding a computer to the HomeGroup.
The wireless signal strength of the standard residential wireless router may not be powerful enough to cover the entire house or may not be able to get through to all floors of multiple floor residences. In such situations, the installation of one or more Wireless Repeaters may be necessary
WiFi often extends beyond the boundaries of a home and can create coverage where it is least wanted, offering a channel through which non-residents could compromise a system and retrieve personal data. To prevent this it is usually sufficient to enforce the use of authentication, encryption, or VPN that requires a password for network connectivity.
However new Wi-Fi standards working at 60 GHz, such as 802.11ad, enable confidence that the LAN will not trespass physical barriers, as at such frequencies a simple wall would attenuate the signal considerably.
For home networks relying on powerline communication technology, how to deal with electrical noise injected into the system from standard household appliances remains the largest challenge. Whenever any appliance is turned on or turned off it creates noise that could possibly disrupt data transfer through the wiring. IEEE products that are certified to be HomePlug 1.0 compliant have been engineered to no longer interfere with, or receive interference from other devices plugged into the same home's electrical grid.