wifi

Generally speaking, it refers to technology that enables two computers to communicate with each other remotely, "using standard network protocols, but without network cabling." Also known as: WiFi and 802.11 networking.

The actual technology behind wireless networking is not a far shot from that of a simple radio or walkie-talkie. The biggest difference is the higher frequency that WiFi cards operate at, allowing for higher data rates. There are actually three industry standards that WiFi cards work with. I have outlined them below:

• 802.11a - transmits at 5 GHz, relies on a coding technique known as orthogonal frequency-division multiplexing (OFDM) for increased efficiency, can handle up to 54 megabits per second, expensive.

• 802.11b - transmits at 2.4 GHz, relies on complementary code keying (CCK), can handle up to 11 megabits per second, affordable.

• 802.11g - transmits at 2.4 GHz, relies on OFDM, retains the 54 megabit per second speed of 802.11a, cost-effective.

Note that the per second megabit speeds above are ideal, and may not be typical of realistic service. All WiFi cards have the capacity to change frequencies. Sometimes, frequency hopping across many channels may be advantageous, to avoid unwanted interference.

For starters, you need to buy a network card, I recommend 802.11g. It has the speed of 802.11a and is much cheaper. Also, 802.11g has "good interoperability on 802.11b equipment." If you are thinking of adding WiFi capabilities to your laptop, you will most likely need a PCMCIA card, which should be inserted into (you guessed it...) the PCMCIA slot on your laptop. Desktops on the other hand require a PCI card. This needs to be installed into the machine. Of course, there are external USB devices that will work for both of the above purposes, but that just seems silly to me, unless you have no slots. Most newer cards should work right off the bat once they are installed with their proper drivers (assuming that they are within range of an operating hotspot or signal). A wireless access point router may be used to set up a hotspot in your home, allowing you to connect wirelessly through your current DSL or cable provider. Apple manufactures a tight little package known as the AirPort Extreme, it is an example of a wireless access point router. The reason I mention it, is that it may be used with an optional directional antenna, resulting in incredible signal range and coverage. And it looks cool. In many cases, WiFi hotspots are protected by wired equivalent privacy (WEP) 128-bit encryption, I suggest you follow suit, lest you wish to become victim to the ruthless bandwidth pirate.

See also: Bluetooth, IrDA.