The simplest way to expand your wireless network is to set up additional access points. This is particularly effective if:

• You have users you can keep on separate access points -- for example, you might put your kids on one access point, and keep the adults on a separate one.
• You have different parts of the property that need coverage -- for example, the third floor of your home is an office that needs coverage, you also need coverage in the kid's bedrooms on the first floor, and you like to work in a converted shed out back.

When you buy additional access points, make sure that they all use the same wireless protocol, such as 802.11b, and be sure to set up security on each one. For those machines that might roam between different wireless coverage areas, such as a laptop, you need to configure the laptop with each wireless access point's encryption keys.
You need to set the same SSIDs (Service Set Identifications) on each additional access point if your laptop or other device will roam and use multiple access points. The SSID identifies the WLAN (Wireless Local Area Network). For example, linksys is the default SSID for most Linksys products. Although you may have overlapping network coverage when you have more than one access point, in reality, a machine will only communicate with the access point with the strongest signal.

To avoid cross talk on overlapping wireless access points, set different broadcast channels. It's also a good idea to choose channels that are noncontiguous. If your first access point is broadcasting on channel 1, set your second wireless access point to broadcast on channel 6 or 10.
Any laptops or other devices that roam from area to area will lock on to the strongest broadcast they discover.

Other points to consider when adding more access points include the following:

• Most access points have an effective indoor range of 150 feet -- less if there are obstructions, metal shielding, or thick walls present. You want only a little bit of overlap (several dozen feet at most) because otherwise you're just wasting effort.
• Although wireless access points placed near the centre of your home (or in your basement or attic) might be invisible from the street, access points placed near the periphery of your home can likely be picked up. Always put security measures in place.
• The speed on a wireless network is determined by two main factors: distance from the access point and number and quality of obstructions between a system and an access point. Even slight changes in the way you point your laptop or even raise the height of a wireless access point can mean dramatic changes.
• Some users have reported great returns by keeping antennas straight or even replacing shorter antenna with longer ones.

Wireless networking involves broadcasting packets into thin air. With the 802.11b and 802.11g specifications, you have only 11 channels on which to broadcast and these overlap. To ensure that you have unique channels with no overlap, you should choose from channels 1, 6, and 11. 803.11a has 12 channels to choose from.
Make sure that other appliances or devices don't broadcast on this frequency. These appliances and devices include microwave ovens, many cordless phones, some power lines, Bluetooth devices, and neighbours with their own 802.11b networks.