Home network
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.
Causes[edit source | edit]
One of the main factors that has historically led to the establishment of a HAN is the out-of-box inability to share residential Internet access among 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 some sort of device that acts as a liaison capable of network address translation (NAT) of packets travelling across the WAN-HAN boundary. Even while the router's role can be performed by any commodity Personal Computer with an array of Network Interface Cards, most new HAN administrators still choose to utilize a particular class of small, passively-cooled, table-top devices which also provide the wireless access point functionality necessary to access the HAN via Wi-Fi–a virtual necessity for the multitude of wireless mobile-optimized devices focused around internet content consumption. The kinds of routers marketed towards HAN administrators attempt to absorb as many duties as possible from other network infrastructure devices while at the same time striving to make any configuration as automated, user friendly, and "plug-and-play" as possible.
Recently however ISPs have starting installing Gateway/Router/Wi-Fi combination devices for new customers which reduces the required steps needed to simply setting the password.
Transmission Media[edit source | edit]
Home networks may use wired or wireless technologies. Wired systems typically use shielded or unshielded twisted pair cabling, such as any of the Category 3 (CAT3) through Category 6 (CAT6) classes, but may also be implemented with coaxial cable, or over the existing electrical power wiring within homes.
Wireless radio[edit source | edit]
Further information: Wireless LAN, Bluetooth, and HomeRF
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.
A wireless network can be used for communication between many electronic devices, to connect to the Internet or to wired networks that use Ethernet technology. Wi-Fi is a marketing and compliance certification for IEEE 802.11 technologies.[1] The WiFi Alliance has tested compliant products certifies them for interoperability.
Existing home wiring[edit source | edit]
As an alternative to wireless networking, 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. With the installation of a home networking device, the network can be accessed by simply plugging the Computer into a wall socket.
Power lines[edit source | edit]
Main article: Power line communication
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.[2] 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.
Telephone wires[edit source | edit]
Coaxial cables[edit source | edit]
DOCSIS, Multimedia over Coax Alliance (MoCA), and CWave carry data over coaxial cables, which are frequently installed to support multiple television sets throughout homes.
Network Hardware[edit source | edit]
An example of a simple home network
A home network may consist of the following components:
Infrastructure devices[edit source | edit]
- A modem for connection to an Internet access service (either a DSL modem using the phone line, or cable modem using the cable internet connection).
- A residential gateway (sometimes called a broadband router) connected between the broadband modem and the rest of the network. This enables multiple devices to connect to the internet simultaneously. Residential gateways, hubs/switches, DSL modems, and wireless access points are often combined.
- A wireless access point, usually implemented as a feature rather than a separate box, for connecting wireless devices
Client devices[edit source | edit]
- A PC, or multiple PCs including laptops, Netbooks and Tablet PC’s
- Entertainment peripherals - an increasing number of devices can be connected to the home network, including TVs, DVRs, digital audio players, video game consoles, and stereo systems
- Internet Phones (VoIP)
- Smartphones connected via Wi-Fi.
- A network bridge connecting two network interfaces together, often in order to grant a wired device, e.g. Xbox, access to a wireless network.
- A network hub/switch - a central networking hub containing a number of Ethernet ports for connecting multiple networked devices
- 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.
- HTPC
Older devices may not have the appropriate connector to the network. USB dongles and PCI Network Interface Cards can be installed in some devices to allow them to connect to networks.
Network devices may also be configured from a computer. For example, broadband modems are often configured through a web client on a networked PC. As networking technology evolves, more electronic devices and home appliances are becoming Internet ready and accessible through the home network. Set-top boxes from cable TV providers already have USB and Ethernet ports "for future use".
Home networking may use
- Ethernet Category 5 cable, Category 6 cable - for speeds of 10 Mbit/s, 100 Mbit/s, 1 Gbit/s, or 10Gbit/s.
- Wi-Fi Wireless LAN connections - for speeds up to 450 Mbit/s, dependent on signal strength and wireless standard.
- Coaxial cables (TV antennas) - for speeds of 270 Mbit/s (see Multimedia over Coax Alliance or 320 Mbit/s see HomePNA)
- Electrical wiring - for speeds of 14 Mbit/s to 200 Mbit/s (see Power line communication)
- Phone wiring - for speeds of 160 Mbit/s (see HomePNA)
- Fiber optics - although rare, new homes are beginning to include fiber optics for future use. Optical networks generally use Ethernet.
- All home wiring (coax, powerline and phone wires) - future standard for speeds up to 1 Gbit/s being developed by the ITU-T (see G.hn)
Comparison to Enterprise
SATA instead of SAS
limited to iSCSI for block storage vs Fibre Channel and 10GBe
Common Infrastructure Issues[edit source | edit]
Wireless signal loss[edit source | edit]
The wireless signal strength 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.
Wired background noise[edit source | edit]
One of the largest challenges posed for those that wanted to utilize the home electrical system for networking is how to combat other electrical noise that would be present due to the use of a power outlet to transfer information. Whenever any appliance is turned on or turned off it creates noise that could possibly dissrupt data transfer through the wiring. IEEE products past the HomePlug 1.0 stage have combated this problem and no longer interfere with, or receive interference from, other devices plugged into a power outlet.[3]
"Leaky" Wi-Fi[edit source | edit]
WiFi often extends beyond the boundaries of a home and can create coverage where it is least wanted, allowing a way for people to compromise a system and retrieve personal data. The usual way to combat this is by the use of authentication, encryption, or VPN that requires a password to access the WiFi.[4]
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 attenuates the signal considerably.
Common Services[edit source | edit]
File Sharing[edit source | edit]
Media Server[edit source | edit]
Management[edit source | edit]
Embedded Devices[edit source | edit]
Most embedded devices for HANs use a minimal Linux distribution that also runs a lightweight HTTP server in the background to allow the user to modify system variables from their browser. These pages use HTML forms extensively and make attempts to offer a styled, visually appealing views.
Windows[edit source | edit]
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 all 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.[5]
Future[edit source | edit]
- "The Cloud" has successfully abstracted away even the most simple of network infrastructure concepts from the average home user. It makes more sense for people without interest or experience in IT to migrate their assets to "The Cloud".
- ISPs provide new customers with an all-in-one modem/router/Wi-Fi
See also[edit source | edit]
References[edit source | edit]
1. ^ “Discover and Learn,” WiFi Alliance, http://www.wi-fi.org/discover_and_learn.php (accessed June 30, 2010).
2. ^ Faure, Jean-Philippe. “IEEE P1901 Draft Standard for Broadband over Power Line Networks: Medium Access Control and Physical Layer Specifications,” IEEE Standards Association, http://grouper.ieee.org/groups/1901/ (accessed June 22, 2010).
3. ^ “Frequently Asked Questions,” HomePlug Powerline Alliance, http://www.homeplug.org/about/faqs/ (accessed June 22, 2010).
4. ^ Wangerien, Brian. "The Challenges of Wi-Fi." Communications News. Encyclopædia Britannica. Web http://www.britannica.com/bps/additionalcontent/18/21597846/The-challenges-of-WiFi.
5. ^ Greg Holden, Lawrence C. Miller, Home Networking Do-It-Yourself for Dummies, John Wiley and Sons, 2011
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