When you walk point you draw fire. Netgear boasted that it was first to ship a draft-802.11n wireless ADSL router and now it has drawn criticism for a product which is likely to prove inferior to its existing products. Netgear says its RangeMax Next ADSL2+ modem router, or DG834N, is the first wireless-enabled ADSL2+ modem router based on the 802.11n draft. The company also claims that it delivers "the fastest data throughput speeds and furthest ranges available in the industry." The ADSL2+ uplink can reach 24 Mbps, while the WLAN may provide more than 100 Mbps (with Netgear quoting 300 Mbps symbol rate).

The point is, the company already sells a product range, the RangeMax 240 WPNT834, which some say is faster and cheaper. RangeMax 240 products are based on the third-generation Airgo chip set--also used in the Linksys SRX400 series--which beat Netgear's Draft-802.11n products in a test run by Farpoint Research's Craig Mathias. Other tests have found that draft-802.11n products interfere with existing WLANs, in ways which degrade the performance of both. "Draft-802.11n products don't just trash other WLANs, they trash themselves as well," said Dave Borison, senior product director at Airgo. "You are better off buying 802.11g."

Netgear does not agree, saying that while both products offer "highest speeds and best range," the DG834N also offers them the "compliant to draft 802.11n" feature. Trouble is, it is not exactly clear what are the benefits of draft-n "feature." Standards should allow products to work together, but Mathias' tests showed that draft-n products do not work together at draft-n speeds. What is more, they are unlikely to upgrade to the eventual 802.11n standard (Netgear admits as much).

With all these problems accompanying draft-n gear, why do companies rush to offer such gear? Airgo's Borison says the reason is that other WLAN chip makers are worried that Airgo's MIMO chips are poised to run away with the top end of the WLAN market, so these chip makers are scrambling to do something -- anything: "Broadcom and Atheros are bleeding, as we sweep across the high end where the margins are good," he said. "We've backed these guys into a corner." Borison is correct, even if his explanation is a bit self-serving. Also, there are nuances in the approaches of different companies that should not be overlooked: Broadcom's approach to draft-n standard (but also USRoboitcs'), for example, is different from other companies' approaches. It's also different from its own approach to the 802.11g standard way back then.

The last word is Mathias's: "It does seem they [Netgear] just wanted to be first to market...But being first to market with a product that isn't ready for production, isn't as good as what they already ship, and claims compliance with a non-standard just boggles the mind."

For more on the draft-n conundrum:
- read this Techworld report

PLUS: USRobotics implicitly criticized Netgear and other companies rushing to market with pre-802.11n products. In a statement released last week, the company said, "Products developed, produced, and marketed prior to the approval of the IEEE 802.11n Draft 1.0 specification are based upon technology that may not be compatible with Draft 1.0, and future, specifications for products...Even early versions of 802.11n Draft 1.0 based products have shown issues with interoperability and legacy networks...USRobotics will release its 802.11n Draft 1.0-compliant products when these issues have been resolved." Release

ALSO: MIMO is expected to become popular as a solution to enhance data throughput and quality of communication in complex propagation environments. There are several different interpretations and implementations considered to be MIMO technology, and MIMO will be adopted in many of the wireless and mobile communication systems in the future. MIMO will be integrated in IEEE 802.11n standards. MIMO is a family of techniques for multi-antenna wireless transmission and reception. There are many ways to accomplish MIMO processing, including MIMO Multiplexing, MIMO Diversity, and others (IEEE 802.11n will adopt Spatial Division Multiplexing (SDM) which is a form of MIMO Multiplexing). The substantial benefits of MIMO come at a price: MIMO also increases the challenges in design and system evaluation and validation, and as a result new measurements need to be considered for testing MIMO systems. Discussion