D-Link AirPlus DWL-650+

Texas Instruments' 22Mb/sec wireless networking solution clearly hasn't set the world on fire, as D-Link is only the second vendor to deliver products using the ACX100 chip and PBCC (packet binary convolution coding) modulation. As with the U.S. Robotics products, D-Link also offers a complete range that includes PCI adaptor cards and a choice of access points.

The PC Card was tested in a Pentium III/800 notebook running Windows 2000 Professional and XP Professional. The installation process was swift, requiring the drivers to be installed prior to insertion. A monitoring utility offers tools for selecting access parameters, monitoring signal strength and viewing a list of discovered access points. During testing, we found that unless we manually selected the 22Mb/sec PBCC rate the notebook automatically connected at 11Mb/sec. The access point is simple to install, although the sparse interface offers only basic management tools and minimal monitoring facilities.

In the performance stakes, every wireless network variation has so far failed to impress, and the same applies to D-Link. Copying a 419MB hard disk image and a 93MB collection of documents from the notebook to a LAN-based Windows 2000 server returned average speeds of 6.2Mb/sec and 4.5Mb/sec respectively. Downloading the same files over FTP saw no significant improvements, while Intel's Iometer utility reported a raw throughput of 7.2Mb/sec between the server and notebook.

The benefits of these products is that they operate in the 2.4GHz frequency range, like 802.11b, so there are no licensing issues. They're backward compatible with 11Mb/sec products too and the PBCC modulation offers slightly better coverage. The D-Link products look good value, but the meagre performance gains don't justify the cost of upgrading from 11Mb/sec.

Author: Dave Mitchell