Using your laptop to access a Wi-Fi network while on the road is usually as simple as finding an open network. The majority of notebooks now have wireless cards built in, and if yours doesn’t have one, you can easily add an inexpensive external wireless card. At home, creating and securing your own network is also simple.

Because wireless connectivity is so userfriendly these days, many people don’t actually understand how the connections are made or how they work. Knowing how everything works together is valuable, because you’ll have some insight as to how you can troubleshoot any wireless problems you may encounter.

The Wireless Radio
A wireless radio is a transmitter that resides on a wireless card. Many laptops have a wireless radio located somewhere inside the unit; however, some are built into cards that a user can plug into a PCI or ExpressCard slot on his laptop. The wireless radio’s job is simple: to transmit and receive radio signals. When these radio signals are transmitted from a network router to the chip in your computer, a Wi-Fi connection results, granting you access to the Internet via that connection.

There are two places on a laptop where you can find and manipulate your wireless radio. Your computer will have a switch for the wireless radio somewhere on the outside of the case, or it will be inside the computer, accessible only from the user interface when the computer is running. In either case, an indicator light on your laptop will show whether the wireless radio is on or off. Generally, this indicator will appear in a bank with other lighted gauges that give information about your system, such as battery power.

If your laptop has an external switch, turning the radio on and off is simple; just slide the switch to the desired position. If your laptop lacks an external switch, you’ll need to turn on your computer and locate the icon that represents the quality of your Wi-Fi reception on the System Tray at the bottom right of your display. Right-click the icon and select Disable Radio. A red X will appear over the icon, indicating that the radio is disabled. To enable the wireless radio, right-click the same
icon and select Enable Radio.

The Connection
A router transmits a network’s signal via radio waves. The wireless card in the computer receives the signal, which enables you to use the network’s bandwidth to access the Internet.

With an unsecured connection, any wireless radio within signal range can connect to the network; it’s a simple matter of sending and receiving radio waves. A secure connection uses encryption such as WEP (Wired Equivalent Privacy) or WPA (Wi-Fi Protected Access) to ensure that only users with an encryption key can access the network.

Connect With Windows XP/Vista
If your wireless radio is turned on, it will automatically search for available Wi-Fi networks when you boot your computer. Each time you connect to a network, WinXP adds it to your preferred list. You can adjust the order of preferred networks by clicking Start, Control Panel, and Network And Internet Connections. Click Network Connections, right-click Wireless Network Connection, and select Properties.

When the Properties dialog box appears, click the Wireless Networks tab and adjust the order of your preferred networks accordingly. For example, move your home network to the top of the list so your computer always looks to connect to that network first.

Vista computers operate in the same manner, with the exception that Vista’s Network And Sharing Center has more automated features to streamline connecting and troubleshooting.

Choose From Multiple Available Hotspots
When presented with a number of networks from which to choose, you should always choose the network that is most secure while offering the best reception. (If you’re at home, this would be your own secure network connection.)

When out and about, be on the lookout for evil twins, which are networks with official sounding names that have been set up by ne’er-do-wells in an attempt to pilfer information from you. For example, if you’re sitting in a coffee shop, look for the network with that establishment’s SSID, or name. It would be a good idea to ask for that information from an employee, a task you may need to take care of anyway to get a WEP or WPA password.

Troubleshoot A Connection
Because Wi-Fi operates on radio frequencies, interference can occur easily. Both 802.11b and 802.11g, the most commonly used Wi-Fi protocols, operate at 2.4GHz. Any appliance or device that operates at that frequency, such as a cordless phone or a microwave, can interfere with your Wi-Fi signal. To avoid this type of problem, position your computer as far away from such devices as possible.

If you’re getting a weak signal and you have a wireless adapter with an adjustable antenna, you can toy with the position of the computer and/or the antenna to get a better signal. Such devices also tend to get better reception than typical internal cards and external cards with no antenna.

There are a number of things that can cause a failed connection. If you’re attempting to connect to a network away from home, the list of possible culprits decreases significantly. Check whether your wireless radio is enabled or if there is an available network that is either open or for which you have an encryption key.

On your home network, any of the above solutions may work, but you also need to double-check your network to ensure the router is on. For all of your wireless networking devices, you’ll also want to make sure the drivers are up-to-date. Manufacturers routinely upgrade, update, or patch their products. If you don’t have the latest drivers installed, your gear may not work properly. Many companies will provide updates automatically, but if you’re having connection problems that you can’t solve, check the manufacturer’s Web site for any new drivers.

When all else fails, it never hurts to restart your computer and router. If you have an external card, remove it and firmly reinsert it before rebooting. A simple system reset solves many problems that otherwise might seem insurmountable.

Tags: Wi-Fi

If you visit Chicago and you want public Wi-Fi access, you’d better go to Starbucks. Once hailed as one of the pioneers of the citywide municipal Wi-Fi movement, Chicago reevaluated its original $18.5 million plan, citing market conditions, and will redeploy the project in the next year or two. On the heels of Chicago’s announcement, Philadelphia and New York have also reported problems getting their Wi-Fi programs off the ground. In fact, MuniWireless.com has downgraded its growth estimates for the industry from 108 percent to 35 percent. One cited reason is the difficulty of making wireless providers live up to the pricing promises the local government has made to its citizens.

Municipal wireless has become a political football,says Craig Mathias, a Wi-Fi expert at market research firm Farpoint Group. City governments have put a lot of constraints on vendors, in some cases requesting free access for every citizen.

One element that may have kept city residents away is how the pricing model was devised. For most cities, access is free at a very low bandwidth (often 500 kilobits per second). Then you pay a monthly fee for higher bandwidth, which subsidizes lower-income residents. Many residents already have home networks with faster connections and newer technologies, such as 802.11n.

But there is one emerging technology that could salvage municipal wireless: WiMAX. It’s a more robust technology that covers a larger area with relatively few towers, as opposed to the hundreds of access points municipal Wi-Fi requires. (Mountain View, California, has about 380 of them.) Analysts say WiMAX is coming, but there have been no successful rollouts in the U.S. yet, so costs are an unknown. Greg Goldman, CEO of Wireless Philadelphia, is not convinced that WiMAX is ready for prime time. WiMAX will encounter the same obstacles and challenges as Wi-Fi in a dense urban environment, he says. It’s still extremely new and is, today, cost-prohibitive.

Meanwhile, as the United States waits for WiMAX to achieve mass adoption, a few cities have already made good on the Wi-Fi promise. In Minneapolis, U.S. Networks built a public-safety network (with the city as a primary customer) and a public-access network covering 60 square miles. In August, when the I-35 bridge collapse killed seven people, cell service went AWOL, but Wi-Fi kept working. Nevertheless, signal reaches only about a third of the city and can be weak. It appears that even the cities that are ahead of the Wi-Fi game still have a long way to go

WiFi networks can reach only so far.

The range of wireless equipment such as the radios and antennas that are built into consumer equipment such as the AirPort Extreme Base Station can vary from network to network, even minute to minute. But when one node of a WiFi network is too far from another, communications between the two break down, and your network doesn’t work.

While WiFi signals are supposed to reach 150 feet in any direction from a gateway, that optimistic figure is rarely reached indoors. One common cause is absorption. Building materials between two points can soak up so much of the signal that one device can’t detect another. Brick is particularly bad for WiFi because brick retains water, which readily absorbs WiFi signals.

As a result, a gateway that delivers a perfect high-speed connection to a laptop from 500 feet away when it has a direct line of sight might be invisible to a laptop that’s 50 feet away when there’s a brick wall between them.

There are two main indicators that your wireless network is having range problems. First, WiFi networks you know are there don’t show up in the wireless menu. Second, when you do connect to a network, the wireless icon in the system menu bar shows just one or two signal-strength bars and frequently slips to no bars.

Read more »