WiFi tries double time

Perhaps because they knew their 54-Mbps technology was unimpressive, companies quickly went about adding firmware upgrades such as “turbo” modes, packet bursting, compression and other techniques to effectively double their theoretical throughput to 108 Mbps. The bad news remains: You still can’t get anywhere near the theoretical maximum transfer rates touted by many vendors. But the good news is that with all their tweaks, the current crop of 802.11g products is, as you’d expect, roughly twice as fast as last year’s. And that means, for the most part, very usable and effective 802.11g wireless technology.

Eight companies chose to participate in the GCN Lab’s most recent 802.11g tests. We asked each vendor to send an enterprise access point and one of its own add-on WiFi adapters. Most sent PC Card adapters; USRobotics sent a USB model.

We set up each access point individually, attaching it to a GCN Lab server at point zero. We then tested each AP in two ways. First we tested the AP communicating with its own vendor-supplied client adapter (two companies did not send adapters). Then we tested the AP communicating with a control radio—an internal Intel PRO/Wireless adapter. On the second test, all APs were evaluated with the same internal adapter in order to isolate AP performance.

In both test scenarios, we transferred 95MB worth of files from the AP to the client at increasing distances. We started with the client right next to the AP, then moved out 10 feet at a time until we reached our maximum distance of 100 feet.

What we found
After weeks of testing, we came to a couple of conclusions. First, 802.11g has come a long way in a year, with increased stability and more consistent signal strength. That said, speeds still aren’t close to the advertised spec of 108 Mbps. Perhaps the routers can burst to those speeds, but none could top sustained transfer speeds of 20 Mbps in our tests.

Second, range and transfer rates are generally better when communicating with an internal WiFi adapter than with a PC Card or USB adapter, especially at longer distances. This makes sense considering the faster bus that internal adapters use. Still, not every agency has the luxury of buying new notebook PCs with built-in WiFi, so the PC Card results are good indicators of the quality of add-in radios, often the cheapest, easiest way of mobilizing a workforce.

In the PC Card tests, the clear winner was a combination of the NetGear ProSafe AP and the company’s WG511T PC Card. Just to make sure the NetGear card really made a difference, we also tested it with the Buffalo AirStation WHR-HP-G54 and Bountiful WiFi Router (neither Buffalo nor Bountiful sent us an adapter of their own). In both cases, the NetGear PC Card performed well.

When each AP transferred files to the control internal radio adapter, NetGear was again the overall winner, although the USRobotics MAXg USR5451 and 3Com OfficeConnect also turned in good performances.

It’s worth noting that we did not give the APs separate grades for ease of setup. That’s because there was little or no difference among the products’ setup routines, and the processes were uniformly smooth. About the hardest thing we had to do was change some APs from dual 802.11b/g mode to 802.11g-only using simple Web interfaces.

When all was said and done, the NetGear was a clear winner—fast, secure and very affordable ($161), especially considering it features power over Ethernet, which is handy for stringing up multiple APs. We’d also recommend the $199 3Com OfficeConnect, which was the only AP we tested to earn Wi-Fi Multimedia certification from the Wi-Fi Alliance for its implementation of IEEE 802.11e quality-of-service standards.

For quick-and-dirty deployments, we’d recommend the even more affordable $80 USRobotics MAXg.

Performance Results: 802.11g WIRELESS ACCESS POINTS

INTERNAL ADAPTER TESTS

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