Home network

A home network or home area network (HAN) is a type of computer network that facilitates communication among devices within the close vicinity of a home. Devices capable of participating in this network, for example, smart devices such as network printers and handheld mobile computers, often gain enhanced emergent capabilities through their ability to interact. These additional capabilities can be used to increase the quality of life inside the home in a variety of ways, such as automation of repetitive tasks, increased personal productivity, enhanced home security, and easier access to entertainment.

Origin
IPv4 address exhaustion has forced most Internet service providers to grant only a single WAN-facing IP address for each residential account. Multiple devices within a residence or small office are provisioned with internet access by establishing a local area network (LAN) for the local devices with IP addresses reserved for private networks. A network router is configured with the provider's IP address on the WAN interface, which is shared among all devices in the LAN by network address translation.

Infrastructure devices
Certain devices on a home network are primarily concerned with enabling or supporting the communications of the kinds of end devices home-dwellers more directly interact with. Unlike their data center counterparts, these "networking" devices are compact and passively cooled, aiming to be as hands-off and non-obtrusive as possible:
 * A gateway establishes physical and data link layer connectivity to a WAN over a service provider's native telecommunications infrastructure. Such devices typically contain a cable, DSL, or optical modem bound to a network interface controller for Ethernet. Routers are often incorporated into these devices for additional convenience.
 * A router establishes network layer connectivity between a WAN and the home network. It also performs the key function of network address translation that allows independently addressed devices within the same home network to establish transport layer connections across the WAN from a single, outward-facing WAN IP address. These devices often come with an integrated wireless access point and 4-port Ethernet switch.
 * A network switch is used to allow devices on the home network to talk to one another via Ethernet. While the needs of most home networks are satisfied with the built-in wireless and/or switching capabilities of their router, some situations require the addition of a separate switch with advanced capabilities. For example:
 * A typical home router has 4 to 6 Ethernet LAN ports, so a router's switching capacity could be exceeded.
 * A network device might require a non-standard port feature such as power over Ethernet (PoE). (IP cameras and IP phones)
 * A wireless access point is required for connecting wireless devices to a network. When a router includes this device, it is referred to as a wireless router.
 * A home automation or smart home controller acts as a gateway and router for low-power wireless networks of simple, non-data-intensive devices such as light bulbs and locks.
 * A network bridge binds two different network interfaces to each other, often in order to grant a wired-only device access to a wireless network medium.

Physical connectivity and protocols
Home networks can use either wired or wireless technologies to connect endpoints. Wireless is the predominant option in homes due to the ease of installation, lack of unsightly cables, and network performance characteristics sufficient for residential activities.

Wireless LAN
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 wireless-capable residential devices 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 802.11n or 802.11ac standards. Wi-Fi is a marketing and compliance certification for IEEE 802.11 technologies. The Wi-Fi Alliance has tested compliant products, and certifies them for interoperability.

Wireless PAN
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 are not thought of as permanent residents of a home network.

Low-rate wireless PAN
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 an additional standard also built on 802.15.4, that was developed specifically with the needs of home automation device makers in mind.

Twisted pair cables
Most wired network infrastructures found in homes utilize Category 5 or Category 6 twisted pair cabling with RJ45 compatible terminations. This medium provides physical connectivity between the Ethernet interfaces present on a large number of residential IP-aware devices. Depending on the grade of cable and quality of installation, speeds of up to 10 Mbit/s, 100 Mbit/s, 1 Gbit/s, or 10 Gbit/s are supported.

Fiber optics
Some neighborhoods support running fiber optic cables running directly into homes. This enables service providers to offer internet services with much higher bandwidth and/or lower latency characteristics associated with end-to-end optical signaling.

Telephone wires

 * VDSL and VDSL2
 * HomePNA support up to 160 Mbit/s

Coaxial cables
The following standards allow devices to communicate over coaxial cables, which are frequently installed to support multiple television sets throughout homes.
 * DOCSIS
 * The Multimedia over Coax Alliance (MoCA) standard can achieve up to 1.5 Gbit/s
 * CWave
 * HomePNA support up to 320 Mbit/s

Power lines
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.
 * HomePlug and HomePNA are associated standards
 * Universal Powerline Association

Endpoint devices and services
Traditionally, data-centric equipment such as computers and media players have been the primary tenants of a home network. However, due to the lowering cost of computing and the ubiquity of smartphone usage, many traditionally non-networked home equipment categories now include 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.

General purpose

 * Personal computers such as desktops, laptops, netbooks, and tablets
 * A network attached storage (NAS) device can be easily accessed via the CIFS or NFS protocols for general storage or for backup purposes.
 * A print server can be used to share any directly connected printers with other computers on the network.
 * IP phones or smartphones (when connected via Wi-Fi) utilizing VoIP technologies

Entertainment

 * Smart speakers
 * Television: Some new TVs and DVRs include integrated WiFi connectivity which allows the user to access services such as Netflix and YouTube.
 * Home audio: Digital audio players, and stereo systems with network connectivity can allow a user to easily access their music library, often using Bonjour to discover and interface with an instance of iTunes running on a remote PC.
 * Gaming: Video game consoles rely on connectivity to the home network to enable a significant portion of their overall features, such as the multiplayer in games, social network integration, ability to purchase or demo new games, and receive software updates. Recent consoles have begun more aggressively pursuing the role of the sole entertainment and media hub of the home.
 * DLNA is a common protocol used for interoperability between networked media-centric devices in the home.

Some older entertainment 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.

Lighting

 * "Connected" light bulbs such as Lifx, Philips Hue, Samsung Smart Bulb, GE Link
 * Zigbee Light Link is the open standards protocol used by current major "Connected" light bulb vendors

Home security and access control

 * Access control: Plume
 * Security alarms: iSmartAlarm
 * Garage door and gate openers: Liftmaster MyQ, GoGogate

Environmental monitoring and conditioning

 * HVAC: Nest Learning Thermostat
 * Smoke/CO detectors: Nest Protect

Cloud services
The convenience, availability, and reliability of externally managed cloud computing resources continues to become an appealing choice for many home-dwellers without interest or experience in IT. For these individuals, the subscription fees and/or privacy risks associated with such services are often perceived as lower cost than having to configure and maintain similar facilities within a home network. In such situations, local services along with the devices maintaining them are replaced by those in an external data center and made accessible to the home-dweller's computing devices via a WAN connection.

Network Layer Configuration
DHCP is used to assign internal IP addresses to members of a home network. A DHCP server typically runs on the router with end devices as its clients. The router itself is a client of the external DHCP servers owned by the internet service provider. All DHCP clients request configuration settings using the DHCP protocol in order to acquire their IP address, a default route and one or more DNS server addresses. Once the client implements these settings, it will be able to communicate on that internet.

Embedded devices
Small standalone embedded home network devices typically 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.

Apple ecosystem devices
Apple devices aim to make networking as hidden and automatic as possible, utilizing a zero-configuration networking protocol called Bonjour embedded within their otherwise proprietary line of software and hardware products.

Microsoft ecosystem devices
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. The Windows HomeGroup feature was introduced with Microsoft Windows 7 in order to simplify file sharing in residences. 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.

Wireless signal loss
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.

"Leaky" Wi-Fi
Wi-Fi 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.

Electrical grid noise
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.

Administration
The administration of proliferating devices and software in home networks, and the growing amount of private data, is fast becoming an issue by itself. Keeping overview, applying without delay software updates and security patches, keeping juniors internet use within safe boundaries, structuring of storage and access levels for private files and other data, data backups, detection and cleaning of any infections, operating virtual private networks for easy access to resources in the home network when away, etc.. Such things are all issues that require attention and planned careful work in order to provide a secure, resilient, and stable home network easy to use for all members of the household and their guests.