REDUCING Range

No problem. You need Wi-Fi wallpaper. See:

plaster your office with this new type of wallpaper. 2.4GHz will be blocked while cellular, radio, and TV go right through. I'm not sure how you would handle the windows, ceiling, and floor with this wallpaper, but it seems like a good idea.

Yes, but it's probably easier to remove the antenna and replace it with a paper clip. Either way, your signal will not just stop at the building walls, but slowly fade out. An attacker would simply need a much higher gain antenna than usual to get a useable signal. For example, if you reduce your TX power by 6dB, then an attacker would only need a 6dBi gain antenna to return the signal to its previous level.

I'm still concerned about the security of Wi-Fi. One way of reducing the

risk of an attack would be to reduce the range so that only the

building I want covered will be serviced with minimal service outside

that area.

Is it possible to lower the wattage of the router to achieve this?

Sure, on a .11b setup only check the box on the setup page that is "allow 11Mbps connections". This will reduce the effective size of your WLAN to 100' or less in many cases. 99% of long distance connections to your WiFi are 1-2Mbps so never allow connections at those rates.

I still do not understand the rational of why reducing the power output of the router, disabling SSID, or enabling MAC filtering will secure a WiFi network.

The network is a cluster of radio transceivers. If you reduce the routers power output, the network cards in the computers will continue broadcasting at full power. Furthermore, they will continue broadcasting their SSID address, and MAC address in the clear, as per

802.11x specifications. There is nothing risky or wrong with this, it is simply the way the network hardware devices communicate with each other.

When we talk about security or securing a WiFi network, we are actually talking about securing the data stream which follows this hardware handshaking. The data contains our credit card numbers, bank statements, email ... things which we would rather not share with our neighbors. Once again, the *only* way to secure this transmitted data is to encrypt it.

What amazes me is how trivial it is to encrypt this data, yet this encryption seems to be the last thing people think about.

Certainly! I've got a Linksys WRT54G with a flashed firmware that allows you to adjust the transmission output. I live in an appartment building myself and it works very nicely to limit the range of your network.

Mine is set from the default 28mW to 2mW. I get plenty of coverage I need in every room.

As others have suggested, you need to ensure WEP/WAP is enabled as well as MAC filtering and disable SSID.

If a hacker wants in and you give him/her enough reason to do it, trust me, they'll get in. The point is that you're using all the necessary tools to provide "reasonable" security.

Good luck!

Entropy1024 wrote in news: snipped-for-privacy@no-mx.forums.yourdomain.com.au:

Yes.

reducing power levels can be useful if you need to support more access points in a given area - you can limit the interference between different access points.

this is suggested in one of the Cisco enterprise setup guides for wireless - so obviously they support it :). See:

Also, some of the ETSI (European) enhancements for 802.11 were designed to reduce power usage / sprectrum pollution by dynamically reducing the transmit power - 802.11h?

FWIW, when the 5 GHz spectrum was initially allowed in the UK, it was illegal to use 802.11a out of doors until equipment supports and is configured for dynamic power control.