11G Goes Gangbusters
On January 31st, Linksys announced that over 100,000 of their wireless products based on the emerging 802.11g standard had been sold in North America since shipping began on December 24, 2002. Linksys expects to ship more than 500,000 Wireless-G products during 1Q of this year. These products are based on "54g" silicon, Broadcom's implementation of the draft standard, expected to receive final IEEE approval this June. Although products cannot yet carry a Wi-Fi label, Broadcom and Intersil have conducted interoperability testing up to the 54 Mbps data rate.
802.11g transmits in the same 2.4 GHz band as 802.11b. It has been eagerly anticipated by those using the 11b standard and looking for faster data rates. Unlike 802.11a -- which also has faster data rates -- 11g has the advantage of maintaining back compatibility with the huge installed base of 11b products (21.5 million shipped in 2002 according to Broadcom). 11g is also expected to work faster over a longer distance than 11a, but is more susceptible to interference from devices like microwave ovens and portable phones.
To get a perspective on expectations for 11g products, we spoke with Jeff Abramowitz, Senior Director of WLAN Marketing at Broadcom. Jeff is delighted with the success of 11g-based products: the ramp rate in getting to 100,000 g-based products sold is 4x as fast as 11b and 12x as fast as 11a. Although some changes came out of the January IEEE standards meeting, Broadcom's 54g silicon is "draft 6.1 compliant" i.e., can handle the change and Linksys will be issuing new software to accomodate it.
We spoke with Jeff about realistic customer expectations for throughput under various circumstances. Broadcom has determined that users of 11b should get 5+ Mbps, users of 11g should get 20+ Mbps. Naturally, the rates will vary with distance. If a user has a mixed network, with their 11g access point supporting both b and g cards, then the b cards will still get 5 Mbps but the g card rates will be slowed to 10 Mbps; coordinating the use of the transmission medium requires overhead communication. Thus compatibility brings with it some reduction in throughput.
Several people at Linksys told us their 11g products were flying off the shelves, and our initial attempt to buy an 11g access point and notebook card bore this out. While visiting our son in Colorado Springs, we found Web sites back-ordered and had to call a number of stores before we finally found what seemed to be the last Linksys 11g access point in stock in town. We are sure that Linksys suppliers will help them re-stock quickly and understand that other vendors will have product available momentarily.
Once we installed the access point and LAN card at our son's house, we did some initial performance tests. We didn't have our complete test rig so we couldn't do extensive testing. However, after setting up our various laptops (there were 4 people and 4 laptops present) we measured 11g speeds from 12 to 16 Mbps - more than three times faster than 11b using the same test in the same places.
Both Linksys and Broadcom say these early "54g" products are upgradable to the final specs. Articles in many trade magazines have warned users that the standard isn't final until it is actually approved and to beware of potential interoperability problems with products based on different chip sets. That didn't deter us personally from buying an access point and cards for our son, although he had no pre-existing wireless networking equipment installed.
We have started more rigorous testing in our home environment so we can compare the performance of 11a, 11b, 11g and mixed mode (b and g) environments. We expect to report our results next month in the Broadband Home Labs section of this report. Please see the Broadband Home Labs section of our website for more information: http://www.bbhcentral.com/bbhl/wifi.html
( www.linksys.com ) ( www.broadcom.com ) ( www.wi-fi.org ) ( www. intersil.com )