When setting up a wireless LAN for your company, there are a couple of things you should keep in mind, according to Craig Mathias, a mobile and wireless analyst and founder of US-based Farpoint Group.
First, forget about conducting a site survey to determine the location of access points. Unless your company has a big facility with a large number of users, site surveys are a waste of money, Mathias said at a workshop at the 802.11 Planet conference in Boston on Wednesday.
"We generally don't recommend site surveys anymore because it is just taking a client's money," Mathias said.
Access points are relatively cheap, between US$600 and US$1,000, so it's easy to buy more if coverage is spotty, he said. Trial and error works just as well as hiring someone to map out where each access point should be, he added.
When buying access points, keep in mind that they all should be the same brand and model, Mathias said. Don't assume that products from multiple vendors will work together just because the vendors say they're compatible, he said. The same goes for Wi-Fi-enabled stickers. Read the fine print to ensure that the devices are compatible, Mathias said.
He also recommended against using spectrum analyzers to determine dead spots for all but the largest networks. Such tools can cost as much as US$2,000 for a handheld and US$24,000 for a large system.
Mathias suggested that vendors' claims about device performance be "de-rated" by 50 percent to 60 percent. And he cautioned that ever-changing environmental conditions affect performance. Those could even include a metal cart rolling down a hallway. Mathias also noted that all the metal tooth fillings, earrings, wristwatches and other accessories that people in the audience were wearing had created a "radio hell" that would affect the WLAN that was running in the hall.
Benchmarking is difficult to do, Mathias added. He said that when he benchmarks a product, he does it in real-world conditions and runs the tests for 48 to 72 hours. Often, he will run conflicting devices to see which can handle interference better.
Companies shouldn't worry about range when configuring a WLAN, Mathias said. Worry more about optimizing a WLAN for capacity. Short-range devices, for example, can be compensated for by adding more access points and antennas. Short-range devices will also save users money because they use less power and allow for greater throughput of information.
As for security, Mathias said that the Wired Equivalent Privacy in 802.11 devices is "junk." He called the security standard a place holder until something better can be built, adding that no one should rely on it. Instead, he said, companies should build in end-to-end security, for example, by encrypting data going over both the wireless and wired parts of the network.
Mathias also advised companies not to worry about outsiders seeking an opportunity to tap into their networks.
"Who is going to sit in your parking lot waiting for something interesting to happen?" he asked.
What an information thief is more likely to do is to break into the Ethernet connection or simply steal a device, Mathias said. Most people don't encrypt the data on their devices, and it's easy for a thief to distract you at an airport and steal your PDA or laptop.
Mathias will participate in a panel discussion on the future of 802.11 Thursday. The conference runs through Friday.