William & Patty Feldman
Multiple computers sharing one printer, family photos stored on a PC shown on a large-screen TV, music files stored on a computer but played through a stereo system, no more waiting to go online until someone else finishes, digital images displayed on any PC in the house showing the view from a wireless camera aimed at the baby’s crib or the front door – the possibilities for work, play and security that are offered by wireless networking at home are extensive and expanding rapidly. Wi-Fi (a trade name of the Wi-Fi Alliance) is wireless local area networking (WLAN) that uses radio waves for transmitting information. Wi-Fi has hit the home front and is off and running. It certainly is looking like the next great thing to take homeowners by storm.
Sales of wireless devices are booming. For example, in July 2003, one major manufacturer of wireless products for the home sold close to 1 million units, about the same number sold in all of 2001. Fueling that growth, over 1 million homes add high-speed interconnection every month. Once homes are wired for that, the next logical step for many is to extend wireless connectivity throughout the home.
Wireless networking has been available for more than 15 years, and has been embraced by early adopters but not by many others. “The recent convergence of various technologies, including high-speed Internet connectivity, improvements in semiconductor chips and other components, ease of installation and operation, lower pricing, along with – perhaps most importantly – the development of uniform wireless standards, which enable easy and assured interoperability of products, have caused an explosion of interest,” notes Michael Wagner, director of marketing at Linksys, a major manufacturer of wireless networking products.
The basic cost of a system is buyer friendly. Prices of components have dropped significantly – systems costing $400 to $500 three years ago are now available for less than $150.
A wireless network is easier to set up than a wired network – no stringing cables around baseboards, fishing wires in walls or having to deal with delicate Cat-5 or higher wires, which, if not installed precisely, can result in reduced signal speed. And unlike a wired network, which confines users to wired areas, it offers freedom of mobility around the house within range, which can be up to 150 feet indoors and more outdoors, without sacrificing data-transfer speed. Expansion of the network requires only the addition of another wireless access card attached to the new device, rather than added wires, Wagner points out.
Another plus – you can use any wireless-enabled notebook or PDA in any public hotspot and log on for free or for-fee Internet access. (A hotspot is a place that offers high-speed Internet connection and wireless connectivity through at least one wireless access point.)
What’s the Story With Standards?
In March 2000, the first set of products based on the Institute of Electrical & Electronics Engineers’ (IEEE, say “I-triple-E”) 802.11b standard were certified by the Wi-Fi Alliance. Currently, there are three wireless networking standards certified by the Wi-Fi Alliance, an industry trade association that sets standards based on guidelines from the IEEE – 802.11b, 802.11a and 802.11g. These standards provide specifications for products.
All products bearing a Wi-Fi logo have been tested and approved by the Wi-Fi Alliance. Until the newer 802.11a and 802.11g standards were finalized, Wi-Fi labeling for home wireless networking was synonymous with 802.11b. Now devices may wear a Wi-Fi label that indicates the standard to which it conforms, as well as its compatibility. Check to make sure the product you are buying has the Wi-Fi specification for the standard or standards you want to follow.
802.11b has been adopted widely for home networking and public hotspots. It operates on the 2.4-GHz band, the same relatively crowded frequency used by cordless phones, baby monitors, microwave ovens, gaming consoles and other wireless devices. The downside to 802.11b is the slow maximum data-transfer rate of 11 megabits per second (Mbps) and the possibility of interference from other devices on the same frequency.
The latest standard, 802.11g, approved this past summer, also works on 2.4, is backward-compatible with 802.11b, and has a maximum transfer rate of 54 Mbps, almost five times faster than 802.11b. Because of its increased speed, it is replacing 802.11b devices. When devices of these two standards talk to each other, they do so at the slower 802.11b rate. When purchasing equipment, look for components that conform to 802.11g. (At this point, there is little price differential.)
The third standard, 802.11a, has a maximum transfer rate of 54 Mbps (the same as 802.11g) and has the advantage of operating in the 5-GHz band, which is less crowded and, therefore, less prone to interference than the 2.4-GHz band. Because it is on a different frequency, 802.11a is not compatible with the other two standards, limiting communication with existing infrastructure. Some manufacturers are offering dual-band 802.11a/802.11g devices, using the “a” frequency for distributing streaming audio and video throughout a home because they can play MPEGs with DVD-quality audio, and use 802.11g for data networking, email sharing, downloading files and the Internet.
802.11b and 802.11g have practical ranges of 100 to 150 feet, while 802.11a reaches out only 25 to 75 feet. Also, 802.11a does not penetrate walls and floors as well as the other two standards.
Theoretical ranges of 802.11b and 802.11g are often stated as much higher – up to 1,000 feet – but they are based on ideal installations where nothing is blocking the line-of-sight path between the transmitter and a receiver, and are rarely (if ever) achieved in practice. For example, every wall and every item in a room can reduce the distance the signal will travel. Also, the farther one gets from the transmitter, the weaker the signal and the slower the transmission rate. While the maximum data-transfer rate for 802.11b is 11 Mbps, that can drop to 2 Mbps or even 1 Mbps at the greatest distance.
In real-life installations, practical, rather than theoretical, transmission distance depends on building materials and room configurations. Plaster walls with lath construction significantly decrease signal distance, as do steel supporting columns. Glass reflects signals, which decreases signal strength. With drywall construction, you can get, optimally, about a 150-foot radius of coverage.
Wireless-network products based solely on 802.11 have superceded other technologies for the home, including HomeRF and RadioLAN. Bluetooth, which is a low-speed, low-power standard for interconnecting various wireless devices likely to be used on the go, complements, rather than competing with, 802.11 equipment. It could be good for wireless keyboards or wireless speakers used at home or for connectivity in public, rather than private, spaces.
To set up a basic wireless network in your home for two computers sharing one broadband or DSL connection, you need two types of components: a single wireless broadband router (a, b, g or a/g), which has a built-in access point, and one network interface card equipped with a radio transceiver for each computer. Any other device that you want to add to the network requires its own adapter. Many computers and laptops come with wireless connectivity already built in.
The wireless networking products for home use typically come with CD-based software that features set-up wizards that walk users, step by step, through the process of configuring the equipment to the home network’s settings.
A broadband router (a base station) acts as a transfer station for the signals from the Internet, your computers and other wireless devices. It routes an incoming signal from the hard-wired cable modem or the DSL you are using for your Internet connection to a remote location. A wireless router, unlike a wired router, has an access point built in, which transmits the signal wirelessly.
Some routers also support wired networks, which is convenient if you already have a wired network and want to keep some components wired or want to add some wired components to your wireless network.
Linksys Wireless-G broadband router (WRT54G), for example, incorporates a wireless access point that lets you connect 802.11g or 802.11b devices to your network; a built-in, four-port, full-duplex switch to connect your wired Ethernet devices, for connecting either four PCs directly or for daisy-chaining out to more hubs and switches for a larger network; and a router function that enables the whole network to share a high-speed cable or DSL Internet connection.
A network interface card links any wireless device you choose to connect your network to the router. When added to a computer or a laptop, it is called an adapter. Every desktop computer not preconfigured for wireless networking needs a PCI (peripheral component interconnect) adapter, which must be installed in the computer tower. Each notebook computer needs a wireless notebook adapter, which installs into the mini-PCI or PCMCIA (Personal Computer Memory Card International Association) interface.
If you do not have a high-speed Internet connection, you cannot access the Internet over the network, but you can still use the wireless network for all non-Internet-based activities.
Where to Install
For best results from your wireless installation, locate the router in an open area, a few feet above the ground, with the antennas straight up, not near any metal objects, and as unimpeded as possible by furniture or other solid objects. Try to put the router in a spot that has a clear path (or as close as you can get) to as many computers as possible or to locations where you are likely to use your notebook. To improve performance, raise the router point as high as you can in the room and maneuver the router slightly to see if you can improve the signal.
Likewise, when using a notebook in any room, a minor adjustment of its angle, which affects the orientation of the adapter card, could improve or degrade the quality of the signal from the router.
“The best way to penetrate obstacles with wireless,” notes Tony Stramandinoli, director of marketing, SMC Networks, “is to buy a router with more output power. The first routers used in homes – and still the basic routers sold today – provide 33 milliwatts of output power. Now units are available with 100 milliwatts of output power. The difference in operation in a home is huge if you are trying to go through walls or between floors.”
Alternately, some companies offer power boosters to their routers that boost a 33-mw signal to 250 mw, and more powerful antennas that can be added to a router.
“If you want to expand the range of coverage of your wireless network, you can add multiple stand-alone access points that are set to repeating mode to act as signal repeaters or signal boosters,” recommends Bradley Morse, vice president of marketing of D-Link.
“The access point receives the signal from the router, amplifies and retransmits it, extending the range. For example, if your router successfully broadcasts three rooms out, but you want to go further to gain wireless connectivity to a fourth or further room, you set up the additional access point in the third room out, where the signal is still strong. The boosted signal now extends the range to rooms four, five and six, going out spherically from that access point,” Morse explains.
Networking Opportunities Abound
With a wireless network in place, there is virtually no limit to what you can do with it.
Many routers now include built-in print servers. You plug your printer into the router, and any computer on the network can print to that printer, regardless of whether any other computer is on or off. The other way to achieve wireless printing from any computer without turning on a dedicated computer is to attach a special adapter, a wireless print server, to your printer. You attach the wireless print server to the printer, and it talks to your computer.
Game aficionados will appreciate the ability to set up wireless connections between Ethernet-enabled game consoles, for untethered head-to-head gaming in the same house or over the Internet. Several manufacturers offer this type of wireless bridge, or Ethernet-to-wireless adapter, for 802.11g environments.
For example, the Linksys Wireless-G game adapter (WGA54G) provides lag-free gaming with communication speeds up to 54 Mbps when connected to other 802.11g devices. It is also backward-compatible with 802.11b, but then connects at the lower 11 Mbps. The adapter is usable two ways. It connects PlayStation2, Xbox or GameCube consoles to the Internet wirelessly for online game playing. And if two game adapters are used, then two players, in the same room or not, can enjoy head-to-head gaming.
D-Link’s DWL-G810 Xtreme G wireless bridge is designed primarily for console gaming at the fast 802.11g speed and also connects any other Ethernet-enabled device, including Internet radio devices, digital media devices, desktop computers and broadband videophones, to an existing 802.11g wireless environment. The unit can operate either ad-hoc or infrastructure mode, allowing owners of PlayStation2, Xbox or GameCube to interact head to head or access Internet gaming services, such as Xbox Live, with the same device.
For laid-back entertainment, you can use a media adapter, or multimedia receiver, to hook up one or several TVs and then show digital photos or videos. (Many digital cameras require downloading of content to a PC before public viewing.) Everyone can sit comfortably and have a clear view, without having to jockey for position in front of the computer monitor. And with photo-editing software in your PC, you can edit your photos on your PC into a digital slide show for professional-style presentation on a large-screen TV, all without having to burn a DVD.
Audiophiles with MP3 (music) files downloaded onto their computers can wirelessly hook up to a traditional analog stereo and listen to music selections on the stereo system any place in the house, without having to burn the music on the disk. The remote TV and stereo devices connect to the back of the TV or stereo with standard hi-fi jacks. The wireless signal is beamed to the router, which can then share the music with any enabled stereo.
For example, SMC’s EZ-Stream universal 2.4-GHz/5-GHz wireless multimedia receiver (SMCWMR-AG) is a universal wireless home-entertainment networking device. Designed for use with an 802.11a/g router, it works with all the 802.11 wireless standards available: 802.11b, 802.11g and 802.11a. It uses 802.11a for streaming video and streaming audio, and for other applications, such as home security cameras. The SMCWMR-AG connects to TVs and stereo systems via standard RCA-type audio-video cable. The device also lets you play Internet radio stations picked up through your broadband connection. The unit features a TV user interface for easy programming of favorite stations.
Other devices you can integrate into your wireless network include TiVo (a digital device for recording TV programs, without commercials, on its hard drive, for playback whenever you want), and very high-gigabyte, wireless, hard-disk storage for video files or MP3s, which you can store away from the desktop, out of sight and sound range. (The fan can be noisy.) You would not get the same transfer rate as you would with FireWire drives, even from an 802.11g device. But if you use it as digital media storage in your home, you don’t need that kind of speed to play it.
Some manufacturers, including SMC, Linksys and D-Link, already have wireless adapters available that can convert any product with an Ethernet port into a wireless device, providing wireless and remote control of that appliance.
The radio waves used on your home network cannot discriminate between your receivers and receivers outside your network. Therefore, to protect your privacy and your data, you need to implement various kinds of network security. The necessary levels are often built into the equipment. Make sure you use them. Often a quick menu lets you activate your choices instantly.
All network devices offer encryption settings, which are factory-set, and can and should be changed.
To help keep your home wireless network private and secure, change to something impartial and personal, both the seven-digit default SSID (service set identifier – the manufacturer-supplied name of the wireless network, which unauthorized users, or hackers, often know or guess at – and also the possibly-guessable, factory-set passwords needed to access any wireless devices. You should also disable the SSID broadcast option (which is only used when setting up a hotspot), and then enable Media Access Control address filtering, if available, which will then allow only devices with recognized MAC addresses to access the network. (The MAC address is a unique hardware address on every Ethernet network device.)
Until last year, all Wi-Fi products included a wired equivalent privacy (WEP) encryption standard that turned out not to be very secure against intruders. Starting this year, many new products contain a new standard Wi-Fi Protected Access (WPA) designed around the still-developing 802.11i security standard. The WPA encryption key changes frequently, keeping the network secure. WPA encryption is backward-compatible with WEP, but the level of security is no greater than the weakest link. Therefore, when setting up the network, use all products with WPA encryption or get firmware, if available, to update products relying on the WEP standard to the WPA standard.
To protect your network against computer viruses and other Internet threats, use anti-virus software that scans incoming files for viruses, and rejects or removes any it recognizes, and firewall technology, which protects against hackers trying to infiltrate your computers or network. A first line of protection, the firewall inspects incoming data packets to verify that they correspond to your requests for information. If they do not, then they are not accepted onto your computer.
Generally, new computers and notebooks come with anti-virus software, which needs to be kept current with updates typically sent over the Internet. Wireless routers come with built-in firewall protection.