Troubleshooting wireless LANs is generally a clumsy business for network engineers. Most available tools run as software on computers, so engineers find themselves walking through testing trying not to drop their laptops and attempting to solve the Wi-Fi problem before the battery dies.
With that in mind, Fluke Networks developed the AirCheck Wi-Fi Tester, a handheld WLAN troubleshooting device that is about the size of a smartphone and can find and connect to access points in 802.11a/b/g/n networks to analyze performance.
"When you're troubleshooting wireless networks, you're moving around," said John Kindervag, senior analyst at Forrester Research. "[Access points] are all over the place, and you have to go where the RF [radio-frequency] signal is."
The portability of the device appeals to Lee Sorensen, a computer technician at Providence Sacred Heart Medical Center in Spokane, Wash. When he is troubleshooting wireless LAN, Sorensen needs to get into some tight spots.
"When you're using something like AirMagnet on a laptop, it's bulky and unwieldy," he said. "With this, you can poke around anywhere to test the RF, even under patients' beds. It doesn't go into the depth that AirMagnet does, but it gives you the information you need quickly, and it tells you any number of troubleshooting indicators."
Sorensen has invested in a full suite of products from AirMagnet for managing and troubleshooting his Cisco Systems wireless LAN, which is composed of about 300 Aeronet 1141 access points. He has also been using the wireless LAN add-on to Fluke's EtherScope II network troubleshooting product, but he said he's never been quite happy with the way it works. He's been beta testing the AirCheck for a few months, and it's helped him solve WLAN troubleshooting problems much faster than he's accustomed to doing with his existing tool set.
"We had a physician in a particular room who carries around a portable notebook, and she complained that every time she sat in this one position in this room, she would lose connectivity," said Sorensen, who admitted that he had doubts that the signal could fail in just one spot in a room based on the position of the user. "I took the AirCheck in, and she was right. There was no question about it. It lost connectivity or it was so weak we couldn't even exchange any packets [between the access point and the AirCheck]. Rather than drag out AirMagnet, I was able to verify what the doctor was saying within 30 seconds. We moved an access point down about 10 feet and improved coverage."
Brad Pritchett, network manager at Eastside Catholic School in Sammamish, Wash., has also been beta testing the AirCheck on his wireless LAN, which is composed of about 100 Meru Networks access points.
"We learned a lot about our network," Pritchett said. "One of the neat things you can do with it is connect to the network and start a continuous ping. Then you can just walk through the building and watch it move from access point to access point, which is really handy. It tells me where the gaps are."
Pritchett also likes the price of AirCheck -- listed at $1,995 -- compared with the EtherScope II he currently has, which costs about $15,000. AirCheck has also addressed some of the problems Pritchett had with WildPackets, a tool he used for troubleshooting wireless LAN in packet capture mode.
"The captured packets are sort of drowned in information," he said of WildPackets. "All you're really seeing is a lot of packets, and you've got to try to draw conclusions with it, which is tough. The other option is to just walk around with a laptop and figure out what's happening with that laptop. It's kind of been a challenge. The wireless environment isn't the equivalent of wired, despite what vendors might suggest, especially when you've got a couple of hundred kids running around with computers, moving from room to room."
Pritchett recently used the AirCheck device to solve a mysterious connectivity problem faced by a school employee who had a dual-mode T-Mobile smartphone and suddenly couldn't connect to the wireless LAN.
"I looked at the Meru monitoring tool, and everything looked fine with the access point near her office," he said. "If I walked over there with a laptop, I would have been able to get a signal and connect, but I wouldn't be sure which access point I am connected to. With the AirCheck, I can walk up to it in Geiger-counter mode and it locates the access point. Then I can connect to it and start ping testing it. Well it wouldn't ping test this time. At that particular time, the version of Meru code had a bug in the firmware in the access points where they would hang occasionally," Pritchett continued. "So I went back to the office and started a reboot of that access point, and her cell phone started working again. The convenience of being able to do that with a handheld device -- to check it out and see what's going on by watching the ping test and the signal levels -- was very valuable."
Let us know what you think about the story; email: Shamus McGillicuddy, News Editor