Company name: D-Link Systems, Inc.
Current retail price: About $59
Platforms: Windows XP, 2000, ME, and 98SE
Bottom line: Seamless WLAN upgrade that's visibly faster, but your mileage may vary
In a nutshell: This 32-bit PC card supports the newly-ratified standard, provides trouble-free compatibility with older WLANs, and works 3-5x faster in new WLANs.
- Simple install includes friendly configuration and monitoring tool
- In our experience, noticeably faster than 802.11b and a notch above 802.11a
- Free firmware upgrade offers compatibility with ratified 802.11g standard; beta firmware also available with WPA support
- Even with 54 Mbps, WAN uplinks and 10BaseT Ethernet are still bottlenecks
- For Win32 operating systems only -- no drivers for Pocket PC, Linux, etc.
- If you need both a and g, you'll want a tri-mode a/b/g card instead
In June, IEEE finally ratified the new 802.11g standard, supporting rates up to 54 Mbps in the 2.4 GHz band shared by older 802.11b products. Like many other vendors, D-Link shipped pre-g-based cards and access points (APs) before the standard was fully-baked. Last week, D-Link posted a free firmware upgrade to bring its AirPlus XtremeG family in line with the final G standard. I decided to install the new 802.11g firmware and take the DWL-G650 out for a test drive.
Installing D-Link's DWL-G650 is simple if you have a Win32 laptop with a free cardbus PCMCIA slot, but it's essential to install D-Link's Configuration Utility before you insert the card. If you're upgrading to standard 802.11g, setup will uninstall old software first. WinXP users can manage WLAN settings in the usual fashion, but I recommend D-Link's Configuration Utility as an alternative. This Utility makes it easy to configure several different security profiles and explicitly choose APs. Link Info makes the outcome very clear, with continuous displays that show quality, signal, and send/receive rates. Pretty typical fare, but wrapped in a simple, intuitive GUI that I prefer to WinXP's View Available Wireless Networks and Status.
And now for the fun part: I paired D-Link's DWL-G650 card with ORiNOCO and Cisco 802.11b APs. I had no trouble connecting this card to my 802.11b APs -- backwards compatibility worked flawlessly. I even saw slightly better file transfer throughput when using the DWL-G650 at 11 Mbps vs. using an 802.11b Cisco 350 card under identical conditions.
Next, I paired the DWL-G650 and Cisco 350 cards with D-Link's DI-624 AirPlus XtremeG wireless router. Under similar circumstances, I found the same transfers just over 3 times faster with G than with B. D-Link claims that G should be up to 5 times faster, and the math makes sense (54 vs. 11 Mbps). However, actual performance depends on many factors, so it's important to realize that "your mileage may vary." For example, using 802.11b at 11 Mbps, you'll get 5-6 Mbps throughput. Since that's slower than a 10 Mbps Ethernet LAN, your Internet uplink will probably be your bottleneck. When using 802.11g at 54 Mbps, the best throughput I managed was about 18 Mbps -- and only when using 100 Mbps Fast Ethernet between my wireless router and directly connected file server. Businesses see a clear-cut benefit in moving to 54 Mbps, but residential users should think hard about how much they'll really gain.
Which brings us to a vs. g. For kicks, I ran the same transfers between an 802.11a SMC PC card and 802.11a AP, under the same conditions. To my surprise, the paired D-Link AirPlusXtremeG products were about 50% faster than this particular 802.11a combo. (Note that I used standard 802.11g, not proprietary g turbo.) Of course, these are just a few ad hoc measurements. I did not attempt exhaustive tests across the variety of conditions and products that would be needed to produce statistically meaningful results.
If you're starting a WLAN from scratch right now, you should consider investing in 802.11g products like D-Link's DWL-G650. G prices have dropped and ratified standards seem to have ironed out some of the earlier b compatibility kinks. If you take advantage of rebates, you can spend less than $50 for this PC card. If you're adding equipment to an existing WLAN that includes both a and b, purchase an a/b/g combo card instead -- for example, the D-Link DWL-AG650 (retailing now for about $79). When purchasing any new WLAN gear today, keep an eye out for new Wi-Fi Protected Access (WPA) support.
About the author: Lisa Phifer is vice president of Core Competence, Inc., a consulting firm specializing in network security and management technology. She is also a site expert to SearchMobileComputing.com and SearchNetworking.com.