WiFi (802.11b/g) Good Practices

WiFi (802.11b/g) Good Practices

You’ve evolved.  You used to sit at a desk with a desktop phone doing your work on a desktop computer.

Now you work on a laptop because you need to get e-mail at work and at home.  At work, you plug and unplug a network cable from your laptop.  At home, you plug and unplug your telephone line and slo-o-o-owly get your e-mail.  You’ve moved from desktop phone to a cellphone — why not go wireless with your data, too?

— what is avaialble —

The most popular way of cutting the cord is to go with a WiFi, or specifically an 802.11b access point (or router) and PC card.  Many companies make wireless equipment that “talks” 802.11b and/or 802.11g — which means, in general, they all talk together.  Cards made by Linksys, D-Link, Netgear, etc. can talk to a Siemens router, for example.

WiFi cards usually have a range of about 300 feet inside and 1,000 feet outside.  The signal can go through walls, floors, wood, glass, etc. and still give a good signal.  There are even specialized antennaes available if you need to cover a certain area or need a high-powered point-to-point link.

— double-edged sword —

Since WiFi is a standard, you can take your laptop with wireless card into most airports and Starbucks Cafes and get internet access.  The problem is that wireless cards and access points are radio transmitters, which means that someone with similar equipment can listen in on your data transmission.  This led the committee that came up with the 802.11b standard to come up with a way to encrypt your data.  Popular levels of encryption are 40-bit and 128-bit.  This prevents the casual snoop from seeing what you browse for on the internet.  It’s not fool-proof, however.  An enterprising student found that WEP (Wired Equivalent Privacy) is flawed.  His work went towards numerous tools to crack the code in about one second after collecting a only a few hundred megabytes of data sent over your wireless network.  In a nutshell, chances are very good that no one cares enough about your data to bother listening in and cracking the code, but do you want to take that chance?  Best practice is to use a VPN (Virtual Private Network) when connecting to work, and use SSL-encrypted websites whenever possible.

— better encryption —

Owing to the flawed security of WEP, the WiFi Alliance has decided to make a new solution for encryption called WPA or WiFi Protected Access.  It’s main points are a time-changing key (TKIP, or Temporal Key Integrity Protocol), and an enhanced authentication method.  These will fill the gap until the IEEE committee finalizes the newer 802.11i security protocol sometime soon.

— best results —

There are really only two scenarios where this will work best in a home-office:

1) If you have more than one machine.  Consider putting a wireless card in each machine you can’t easily run a cable to.  The cable and wired cards are less expensive, but you’ll spend a lot more time running cable behind walls and through ceilings.  You still get the benefit of all of your machines on the same network, but less hassle.

2) If you have a broadband connection to the internet, it will feel more worthwhile even with just one machine, a wireless broadband router, and your wireless-enabled laptop.  You can work just about anywhere in your house without plugging in, and if you eventually get more machines, you can just have them into the wireless router, too.

In a corporate environment, it is best to err on the side of more safety.  Your access point should be set up with the best encryption available, it should probably use rotating keys, a RADIUS authentication/accounting server (Remote Access Dialup User Service) and you should require your wireless users to use a VPN at all times.

— what to get —

We’ve found that Linksys, Netgear and D-Link are quite acceptible entry-level systems.  We prefer the Linksys 802.11g equipment, especially the non ”SpeedBooster” models of the WRT-54g router.  Siemens has proved troublesome.  Cisco’s Aironet systems, while exceptional in quality and privacy (they can use proprietary encryption), are expensive.  Nota bene: Cisco acquired Linksys in March of 2003.

 

LinksysNetgear D-Link CiscoAironet Siemens
Speed
(megabits per second for 802.11b)
11 22 11 11
Speed
(megabits per second for 802.11g)
54 54 54 54
Cost, PCMCIA card for laptop
(approx.)
$75.00 $75.00 $175.00 $75.00
Cost, PCI card for desktop
(approx.)
$75.00 $75.00 $300.00 $75.00
Reliability Good Good Excellent Not so good