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 SMC EZ Connect 802.11a Wireless Access Point and CardBus Adapter By Eric Griffith
February 8, 2002
Model Reviewed: For fast wireless, newly available 802.11a products are the answer. 802.11a promises 54Mbps second speeds - and sometimes more with tinkering by the manufacturer. It also runs in the 5GHz range using a modulation technique called orthogonal frequency division multiplexing (OFDM), which breaks up fast serial information signals into several slower sub-signals that are transferred at the same time via different frequencies, providing more resistance to radio frequency interference. You can't go wrong, right? Sorry, there are always caveats. Much like with Wi-Fi's theoretical throughput, promised speeds are never delivered in real life. 54Mbps is not going to happen, even with a laptop in the same room as an access point -- though you will see anything from three to five times the speed of Wi-Fi. Also, 802.11a isn't compatible with 802.11b - in fact, until the Wireless Ethernet Compatibility Association (WECA) gets the Wi-Fi5 logo program for 802.11a products running, there's no guarantee 802.11a products from different companies will interoperate well. If you can live with those caveats - especially if you're just moving to a wireless LAN for the first time - 802.11a deserves consideration. One of the first companies to deliver products in this space is SMC Networks. FeaturesThe two SMC EZ Connect 802.11a products use the Atheros Communications chip set that's in just about all 802.11a products currently available. Both come with exactly the same software on CD: the EZ Connect 802.11a Configuration Utility, which provides several pages of info for client systems, or a link to the Web-based setup for the access point, depending on the system you access the software with (see Setup below). The SMC2755W access point is a simple box with dual external, adjustable antennas. It's solidly built and has three indicators on the front for power, Ethernet link activity with the wired network (green for 100Mbps or amber for 10Mbps), and another for wireless activity (either searching for the network or sending/receiving data). As with any access point, installation is no more than a patch cord between the access point's RJ-45 Ethernet jack and your hub/switch, and power. There's nothing more to plug in. Security on the SMC products ups the ante in Wired Equivalent Privacy (WEP) encryption a bit: in addition to 64-bit and 128-bit WEP, the SMC's support 152-bit keys, all using the RC4 encryption algorithm. However, the access point doesn't support VPN tunnels, RADIUS, or any other kind of encryption. SetupWhen it comes to getting these products running, you might think you've got plug-and-play, but not quite. SMC's 802.11a PC Card slides into place on any unit with a CardBus slot (the documentation says it will not work with a 16-bit PCMCIA slot) and starts the usual Windows Hardware Install routine, finding drivers on the included CD-ROM with no problem. The EZ Connect 802.11a Configuration Utility brings up all sorts of information about the client card, however settings adjustments for the card are not made with the Utility. For that, you need to go into Control Panels. The manual says to click on "SMC NIC Configuration" but there's no panel by that name - it's listed as "Atheros NIC Configuration." Once the control panel is located, adjusting card settings is a breeze. One of the tabs on the EZ Connect 802.11a Configuration Utility is for "Station," which should show a listing of all the access points on the network and double clicking on those listings, should launch the Web browser-based management interface for the AP. When I got the PC Card installed, it did show the access point, but no IP address - it just said "searching." To get to the management interface for the access point, the EZ Connect 802.11a Configuration Utility should be installed on a PC attached to the wired network. When I tried to install it, I ran into my first issue: an error that came up on systems with Windows 2000 and XP that said, "This version of the WMI Core Components is only supported on Windows NT 4.0 Service Pack 4 or later versions of Windows NT 4." According to SMC tech support, this is a known problem but doesn't impact the use of the software, though on one of my Windows 2000 desktops it wouldn't launch the utility at all. When the utility does launch, it shows nothing but the "Station" tab since it doesn't see the wireless PC Card. The access point was not viewable. The problem: the access point ships with a default IP address of 192.168.1.20. All of my PCs were setup with IP addresses of 192.168.0.xxx. I had to change the third octet of one wired system's IP before it would see the access point. Once I changed the access point to match my other systems, everything was fine. This isn't documented anywhere, though tech support mentioned working through it with more than just me, so it probably should be. Wireless PerformanceMy tests with NetIQ's Qcheck freeware were interesting, to say the least. Using SMC's Turbo mode, a non-standard mode in the EZ Connect 802.11a products brought about by engineering tweaks, the access point to client throughput topped out at 31Mbps for distances between three and 15 feet, whether on the same level and with a floor in between. By the time the client was two floors away, throughput dropped to 9Mbps -still respectable compared to 802.11b, but nowhere close to the speed SMC suggests is possible. When the client was placed in an upstairs closet, two flights away from the access point, the signal between the two was repeatedly lost, a problem I've never encountered during testing of several 802.11b/Wi-Fi products with the same setup. When trying to step the two products back to regular 54Mbps second mode, the client card wouldn't find the access point again. It seems to only work with the turbo mode. Resetting the access point to the factory settings and starting from scratch fixed the problem. Throughput performance in the same room hovered at 21Mbps, and dropped to about 18Mbps one floor away. On the second floor the same problem cropped up, the signal from the access point dropped so often I couldn't even test the throughput to the client laptop. SummarySmart shoppers don't buy a car model the first year it's marketed in case all the bugs aren't worked out of the system, and there's a similar reason people avoid version 1.0 software and hardware. The SMC EZ Connect 802.11a products definitely have a few flaws, but it's hard to overlook one factor: they're the fastest wireless networking products we've seen yet. Early adopters should use caution, but give SMC's 802.11a products due consideration - as long as all your client computers are on the same floor. Want to talk about it? Use the Forums.
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