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Networking Answers: New Technologies

The first step in connecting your PCs is to choose a network technology. And these days you have plenty of options, even if you don't want to run new wires. Each comes with its own advantages and disadvantages, from networks that use existing phone or power wires to different types of wireless networks. To get a feel for which ones work best, we plugged in and tested power-line (HomePlug) and phone-line (HomePNA) networking hardware in a typical home office. We also set up two kinds of wireless networks: 802.11b (also known as Wi-Fi) and the fast, new 802.11a (or Wi-Fi5), checking out their performance at opposite ends of a 20-foot room, 40 feet apart in adjacent rooms, and (when the weather allowed) while working outside on the patio. (See the features chart for more details on performance and pricing.)

Wi-Fi networks may be the best choice for most small networks. Though the Wi-Fi networking hardware we tested did not ace our speed tests, it offered the best combination of reasonable prices and quick setup. The more expensive Wi-Fi5 equipment performed about twice as fast (averaging 13 mbps). Power-line products turned in impressive results too, cruising to the second-best times in our tests. Phone-line products, the budget choice in the networking lineup, were among the easiest to set up--Windows XP recognized the adapters and installed the drivers without our having to insert a CD. Simple but sluggish: Phone-line products also provided the slowest file transfers.

Any of these no-new-wires networking technologies has more than enough bandwidth for basic file, printer, and Internet sharing. In some cases, though, you might want to consider mixing the products to create a hybrid network (see Scenario 4) that gives you the roaming ability of wireless products with the reliability of wired network hardware.

Q: What's the fastest wireless networking technology now available?

A: Wi-Fi5

Wireless hardware offers some obvious benefits (such as surfing on the porch) and some not-so-obvious drawbacks, including real-world speeds that start slower than most wired networks and drop with distance, as well as questions about whether you'll have a strong enough signal to support a connection. But while Wi-Fi5 equipment--the latest generation of wireless networking hardware--is too expensive for most home users, it's the fastest technology we tested, and it offered easier installation than did comparable Wi-Fi products.

Surprisingly, the Intel Pro/Wireless 5000 CardBus Adapter came with only a small paper instruction sheet. Installation was a breeze, however. Using default settings, we networked two notebooks with Pro/Wireless 5000 adapters in about 15 minutes. Since Wi-Fi5 equipment is so new, and since vendors are targeting businesspeople on the move (at least around the office), PCI cards weren't available in time for our testing. As a result, we tested WiFi5 using PC Card network adapters on two laptops running Windows XP.

Wi-Fi and Wi-Fi5 hardware installations are similar except in one detail: For Wi-Fi5, you won't find any USB adapters, a mainstay of Wi-Fi networking. USB connections would create bottlenecks in 802.11a networks, which can transfer data more than twice as fast as the USB 1.1 connections most PCs have.

The 802.11a standard theoretically tops out at a blistering 54 mbps, though we never achieved even half that speed in our tests. Still, the WiFi5 cards we evaluated delivered impressive real-world performance. Our throughput rates peaked at around 22 mbps and averaged around 13 mbp--that's more than twice the speed of the Wi-Fi, HomePlug, and HomePNA equipment we tested.

The drivers for most wireless adapters assume that you'll be using an access point to relay signals between your PCs. In network-speak, this is called "infrastructure" mode. But wireless cards can also work in "ad-hoc" mode, where the cards communicate directly with each other--no access point needed. Unfortunately, Wi-Fi5 access points aren't yet available with built-in routers, so to share your broadband Internet connection, you must use an ethernet cable to connect the access point to a stand-alone router. You can pick up a router with a built-in firewall for $100 or less. Or you can set up a single always-on PC, and use Windows Internet Connection Sharing to share its dial-up or broadband connection.

Though Wi-Fi5 offers a higher level of encryption than Wi-Fi, it still uses Wired Equivalent Privacy, which critics say is too insecure. For home use, however, WEP combined with common sense security setups should be adequate.

Wi-Fi5's biggest hang-up is that it's incompatible with less-expensive Wi-Fi networks. Whereas Wi-Fi5 operates in the 5-GHz band, Wi-Fi operates in the 2.4-GHz band (as do some other electronics devices, such as cordless phones and microwaves, which can cause interference). Dual-mode access points to bridge communication between the two wireless technologies are expected later this year, though availability and pricing have yet to be announced. Later this year, 802.11g networks promise to combine the speed of 802.11a with 802.11b compatibility.

A wireless Wi-Fi5 PC Card adapter will set you back $130 to $170, and an access point currently costs between $300 and $400. However, equipment costs will drop as these products spread through the market. Businesses looking to extend their existing networks with the fastest wireless networking equipment available should look into Wi-Fi5.

Q: What's the lowest-cost technology for starting a wireless network?

A: Wi-Fi

Attracted by the idea of roaming around with your constantly connected laptop, but not ready to commit to Wi-Fi5 at $170 per network adapter? Consider the widely used Wi-Fi standard instead. Wi-Fi hardware is fast enough for shared Internet access and most file-sharing duties in homes or small offices.

We installed Wi-Fi adapters from two vendors, Proxim and Netgear, and each installation took about half an hour. Since lots of Wi-Fi products are available, and you can mix and match hardware from different manufacturers, we wanted to test compatibility right out of the box.

If you use adapters or access points from different manufacturers, you'll need to tweak a couple of settings to get everything running smoothly. The SSID (or Service Set Identifier, a name you enter to identify the wireless network) and the radio channel settings (there are 11 channels to choose from) need to match for each wireless adapter. These quick parameter changes are easy to make--and to forget. If they differ at all, the network won't work, and you'll be left to angrily curse the red light in your system tray that signifies no connection.

We plugged in one PC Card and one USB network adapter (in many cases you can connect the adapter to your PC without powering the PC down, but check your manual to make sure), and then installed the drivers and the configuration utility. That's when we hit a minor roadblock: The devices were set, by default, to infrastructure mode. Since we hadn't (yet) set up an access point, we needed to change the mode setting to ad-hoc.

As with Wi-Fi5, the biggest installation hurdle we faced was lackluster documentation. One manual failed to cover XP installation, for example, notwithstanding the XP-ready decal on the box. Another product came only with a small poster to serve as an installation guide--the full manual resides in a PDF file on the accompanying CD-ROM.

Most networks require at least one Wi-Fi access point. Adding an access point (you can find them for $150 and up) effectively doubles your wireless network's range. To share a cable or DSL connection, look for an access point that has a built-in router; this will allow you to share Internet access with each PC in your network (see Scenario 2).

Though Wi-Fi networks are slower than Wi-Fi5 ones (Wi-Fi hardware consistently achieved speeds of about 4.1 mbps in our tests), they're also far less expensive. If you search online vendors, you can find a Wi-Fi network adapter for as little as $80. And since Wi-Fi has been around longer than Wi-Fi5, a greater range of compatible products exists, including routers, print servers, and various types of access points, as well as PCI and USB adapters for connecting a desktop.

Typically, Wi-Fi products offer you a relatively painless way to get started with wireless networking. For the most part, we found that roaming around with a connected laptop worked well. If any adapter is more than 100 feet from an access point, however, you're in for headaches. Too many obstructions, such as walls, brick, and steel, will also greatly reduce your range. In these situations, a wired or hybrid network is a better choice.

Q: What technology can I use to network a group of computers through my existing phone jacks?

A: HomePNA

Phone-line networking hardware (HomePNA) is the oldest of the no-new-wires network standards we looked at, and it's the least expensive. For $30 to $70 per computer, you can quickly create a network connection anywhere that you have a working telephone jack.

Two D-Link phone-line adapters--which came as part of D-Link's DHN-920 kit--readily connected to PCs in adjacent rooms of the test site, about 40 feet apart. Windows XP automatically recognized the USB phone-line adapter. Then we connected each phone-line network adapter to a regular telephone jack with the included phone cable.

HomePNA hardware won't disrupt your telephone use. When we made phone calls while sending files across the two-PC phone-line network, our throughput remained constant. Each network adapter includes a phone-line splitter, so you can run a cable from the network adapter to a telephone or answering machine or use a separate splitter to split the phone line at your wall jack.

The phone-line-to-USB network adapters were the slowest of the products we tested, consistently transferring data at about 4 mbps. Speeds drop off as line noise increases, so your results will depend on the quality of your line.

Their low cost makes phone-line networks the budget choice for simple file and network sharing in a home or small office that has plenty of phone jacks. Unlike with ethernet hardware, you don't need a hub to connect multiple computers to a phone-line network. Keep in mind, though, that phone-line networks only cover one line at a time. So a network that is set up over the main phone line won't work with a separate fax line or with the line you installed to keep the kids from tying up your main number.

Phone-line networks aren't quite as flexible as either power-line networks (since most homes don't have phone jacks in every room) or wireless equipment (because you can't really roam while you're tethered to a phone jack). But if you're simply connecting a few household desktops so that they can share a modem or broadband connection (see Scenario 1), phone-line products are an excellent way to save money.

Q: What technology will let me use electrical outlets to start a network?

A: HomePlug

Maybe you'd like to start a wireless network, but you're concerned that wireless adapters start to lose their signal and drop in speed as you place them farther apart. Still, you'd like to connect from any room in the house--even rooms without phone jacks. What should you do? Consider a power-line network. HomePlug power-line network adapters will cost you about $150 for each connected PC and $179 for a power-line cable/DSL router for sharing a broadband connection.

After all, since most rooms in your house have multiple outlets, plugging into power-line networking could give you an instant network connection just about everywhere in your home. That level of flexibility has made power-line products one of the most anticipated networking technologies to hit store shelves in some time, despite some rather unimpressive early implementations.

As with phone-line products, you don't need a hub to connect more than two computers using HomePlug. And notwithstanding its name, HomePlug can be a great way to connect a small office. Your building's wiring is your hub, and the power line hardware transmits data using those wires, while drawing its power from them. You can plug into power strips, though you should avoid ones with surge protection or line conditioning, either of which can negatively affect power-line data signals. Power-line network adapters contain their own surge protection circuitry, which protects both the adapter and your PC.

The previous iteration of power-line networking products drew ire from folks disappointed by its less-than-blazing 350-kbps speed--much too slow for sharing large files. We looked at a preproduction version of a second-generation HomePlug network adapter from Linksys (the PLUSB10), which offers a theoretical top speed of 14 mbps. In tests at an apartment and at a detached home, real-world throughput topped out at slightly over 5 mbps. Your results might be quite different, depending on line noise.

We connected the adapters to electrical jacks 20 to 40 feet away, with no speed difference over those distances, and the power-line network fared better than both Wi-Fi and phone line in terms of raw speed (see How Fast Are They Really?). Setting up USB power line network adapters proved as simple as installing a phone line network product. And once the drivers are installed, you're ready to go. The ethernet-to-power-line bridge that we tested (Linksys's PLEBR10) didn't require new drivers because it connected through the preinstalled ethernet adapter in the test PC.

If you often find yourself crouching under your computer desk to install new equipment, the additional wire that both power-line and phone-line products add to the tangle could be annoying. In addition to being cable-free, wireless network adapters come in less-cumbersome PC Cards and USB adapters that make the equipment less obvious; from an aesthetic standpoint this might be more important at home than at the office.

Still, HomePlug products are a good bet for most homes and should become more attractive as their prices drop over the next 12 months. Power-line networks avoid the security weaknesses of wireless networks while still permitting you to work from any room in your home.

A power-line network can also serve as an intriguing extension to an existing network, creating a hybrid network. One of the power-line network adapters we connected to a desktop was, in fact, a power-line-to-ethernet bridge, which can link a power-line network to a wireless network, for example. For the test, we connected one end of the bridge to the desktop's ethernet network card via RJ-45 cable.

Power-line products instantly extend your network to any outlet in the house and, perhaps just as important, to places where wireless products might have trouble maintaining a strong signal. The back yard is still better served by wireless, but a power-line network may be your best bet for the attic or the basement.

--Paul Heltzel

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