How...Wi-Fi Works?????

If you've been in an airport, coffee shop, library or hotel recently, chances are you've been right in the middle of a wireless network. Many people also use wireless networking, also called WiFi or 802.11 networking, to connect their computers at home, and an increasing number of cities use the technology to provide free or low-cost Internet access to residents. In the near future, wireless networking may become so widespread that you can access the Internet just about anywhere at any time, without using wires.

WiFi has a lot of advantages. Wireless networks are easy to set up and inexpensive. They're also unobtrusive - unless you're on the lookout for a place to use your laptop, you may not even notice when you're in a hotspot. In this article, we'll look at the technology that allows information to travel over the air. We'll also review what it takes to create a wireless network in your home.

A wireless network uses radio waves, just like cell phones, televisions and radios do. In fact, communication across a wireless network is a lot like two-way radio communication. Here's what happens:

1. A computer's wireless adapter translates data into a radio signal and transmits it using an antenna.
2. A wireless router receives the signal and decodes it. It sends the information to the Internet using a physical, wired Ethernet connection.

The process also works in reverse, with the router receiving information from the Internet, translating it into a radio signal and sending it to the computer's wireless adapter.

The radios used for WiFi communication are very similar to the radios used for walkie-talkies, cell phones and other devices. They can transmit and receive radio waves, and they can convert 1s and 0s into radio waves and convert the radio waves back into 1s and 0s. But WiFi radios have a few notable differences from other radios:

• They transmit at frequencies of 2.4 GHz or 5GHz. This frequency is considerably higher than the frequencies used for cell phones, walkie-talkies and televisions. The higher frequency allows the signal to carry more data.
• They use 802.11 networking standards, which come in several flavors:
  • 802.11b was the first version to reach the marketplace. It's the slowest and least expensive standard, and it's becoming less common as faster standards become less expensive. 802.11b transmits in the 2.4 GHz frequency band of the radio spectrum. It can handle up to 11 megabits of data per second, and it uses complimentary code keying (CCK) coding.
  • 802.11g also transmits at 2.4 GHz, but it's a lot faster than 802.11b - it can handle up to 54 megabits of data per second. 802.11g is faster because it uses orthogonal frequency-division multiplexing (OFDM), a more efficient coding technique.
  • 802.11a transmits at 5GHz and can move up to 54 megabits of data per second. It also and uses OFDM coding. Newer standards, like 802.11n, can be even faster than 802.11g. However, the 802.11n standard isn't yet final.
• WiFi radios can transmit on any of three frequency bands. Or, they can "frequency hop" rapidly between the different bands. Frequency hopping helps reduce interference and lets multiple devices use the same wireless connection simultaneously.

As long as they all have wireless adapters, several devices can use one router to connect to the Internet. This connection is convenient and virtually invisible, and it's fairly reliable. If the router fails or if too many people try to use high-bandwidth applications at the same time, however, users can experience interference or lose their connections.

Canon PowerShot S3 IS.......This advanced camera offers a 12X zoom, plenty of control buttons, and a swiveling LCD.

The 6-megapixel Canon PowerShot S3 IS ($500 as of August 25, 2006) offers a lot of features for the price. Among the most attractive of these are its optical image stabilization, 12X optical zoom, fast maximum shutter speed, and swiveling 2-inch LCD (which comes in handy for shooting at creative angles).

The S3 IS fit well in my hand and felt sturdy, though it's light and fairly compact. The plentiful buttons offer quick access to manual settings such as ISO, macro mode, and manual focus. Jumping into the menus, you can access a number of other settings such as color controls, exposure bracketing, and focus bracketing--the last of which might come in handy when you use the camera's manual focus. Even though the LCD or electronic viewfinder magnifies details of your shot to help you focus, it's not enough to get an exact lock on your subject.

I found the camera's optical image stabilization quite effective at countering minor shaking and delivering an image with fairly sharp details. The powerful 12X zoom was a joy to use, though the ring that controls it (and that surrounds the shutter button) took a little getting used to. Turning the dial slightly activates the zoom more slowly than if you crank the dial all the way over. This response seems squirrelly until you get accustomed to it.

One interesting feature, called movie snap, allows you to trigger the shutter to capture stills while shooting a movie. When you watch the movie, the screen will go blank momentarily at the points where you shot still images, but the soundtrack will remain continuous.

In our lab tests, the S3 IS delivered impressive overall image quality, its best attributes being color and exposure accuracy. The camera's scores for distortion and sharpness, however, were below average. In my informal shots, the S3 IS generally delivered good results, though I did notice a fair amount of noise in landscape photos taken just after sunset and in close-ups taken during daylight in macro mode. In our battery life tests, the S3 IS's battery lasted for just 331 shots on a single charge.

-- Eric Butterfield

Nokia-E62....what say???????

This newcomer to the PDA phone scene has quickly become a top contender thanks to a bevy of features and a keyboard that's a pleasure to type on. Available from Cingular, this handset lacks high-speed HSDPA support (it does support EDGE) and has some interface quirks that take a little getting used to, but it's one of the most capable smart phones on the market.

As a phone, the E62 is on the quiet side, so your callers may be hard to hear. Dialing is easy, however, and the unit is comfortably light to hold. Talk-time battery life is excellent, reaching the 10-hour maximum that we test for.

The E62's roomy keyboard is its biggest draw: It's one of the most spacious arrangements I've ever seen on a candy-bar handset, with wide, flat keys that are beautifully sized and spaced. Setting up e-mail is a breeze, and sending and receiving messages are just as simple. The E62 handles attachments with aplomb, and its included office suite lets you edit documents easily. Though the included MP3 player is loud and clear, you'll want to use the bundled headset in lieu of the tinny internal speaker.