Besides the numerous comments still to be resolved before draft 3 of the 802.11n standard appears, a patent problem is hanging over the proposal like a storm cloud on the horizon. To become an IEEE standard, everyone with a patent that touches that standard must sign a LoA (Letter of Agreement). The LoA states that the patent holder won't sue anyone using his or her patent in a standard-compatible device.

That's bad news to would-be 802.11n users. Commonwealth Scientific and Industrial Research Organization (CSIRO), an Australian government research group, has not signed off on 802.11n. Denis Redfern, CSIRO's vice president of licensing, is reported to have said that the research body is "happy to confirm that CSIRO continues to be willing to license these patents on a worldwide basis to manufacturers of notebook computers, access points and other wireless-enabled products that would otherwise infringe the patents." But Redfern also said that Wi-Fi vendors haven't been willing to reach licensing agreements.

Indeed, Apple, Dell, Intel, Microsoft, HP and Netgear are attempting to overturn CSIRO's patents. CSIRO has already won one lawsuit concerning these patents against Buffalo Technology. The group shows every sign of continuing its aggressive patent defense. And as for the IEEE 802.11n LoA? In September 2007, CSIRO refused to offer any amnesty to IEEE members that infringe on its patent.

The heart of this conflict? Money. Depending on whom you choose to believe, CSIRO wants a reasonable license fee for its technology—or it wants to charge OEMs (original equipment manufacturers) outrageous fees. Fees, that is, to be passed on to you as additional dollars per 802.11n device.

If this patent fight is the only remaining issue, it's possible that 802.11n will become a de facto standard even if it still won't be a de jure standard anytime soon. That's because, as Molly Mulloy, public relations spokesperson of wireless OEM Broadcom, explained, "We believe that draft 2.0 of the 802.11n specification is very solid. All of the major technical items have been resolved, and only relatively minor wording issues remain. Therefore, we expect the final 802.11n standard to be ratified as planned in the second half of 2009."

But What About My IT Budget?

So, should you upgrade now? Gruber said, "It is up to the businesses if they want to take the chance. Although a majority of the vendors are stating that their "draft n" products will be upgradable to the final standards through software updates, there is still some uncertainty in the industry."

It's noteworthy, Gruber continued, that, "the Wi-Fi alliance [the industry association promoting 802.11 wireless networking] claims, 'At this point, it is not possible to determine whether forward compatibility' with the final standard will exist."

Mulloy, however, stated, "All of Broadcom's draft-802.11n solutions shipped to date should be able to support the final specification with a firmware upgrade. Therefore, our existing products should continue to interoperate with Wi-Fi devices certified for the final 802.11n standard."

Stan Schatt, ABI Research's vice president and research director for wireless connectivity, is also optimistic about 2008's draft 2.0 802.11n equipment being compatible with tomorrow's hardware. "At this point, with the Wi-Fi Alliance's operability testing and certification in full swing, there are no longer any major concerns about buying prestandard equipment," he says. If they haven't done so already, most very conservative Fortune 500 companies will at least pilot draft-n products (if they haven't done so already) although they might wait until 2009 and the final standard for massive deployments, according to Schatt. "Early adopters, such as health care and universities, are already involved in some major deployments involving thousands of APs," he added.

Be that as it may, Gruber remains suspicious of vendors' 802.11n claims, although he hasn't tested any draft-n devices. Yet he cites independent reviews in which "many draft-n SOHO routers have not lived up to their claims in terms of speed. The enterprise vendors I have spoken to claim that their devices reach quoted speeds in real world tests."

Another performance problem that most vendors shy away from explaining is that, while 802.11n is compatible with existing 802.11b/g WLANs (wireless local area networks), it does so at the expense of speed. Cisco, to its credit, addresses this concern head-on in its 802.11n Wireless Technology Overview: "An 802.11n network can incorporate 802.11a/g clients with minimal performance loss. However, as with today's 802.11g networks, operating in a mixed environment that includes 802.11b clients can substantially affect throughput. (The throughput of today's 802.11g networks may drop from 25 Mbps to as low as 7 Mbps when 802.11b clients enter the environment, and 802.11n networks will suffer a comparable performance decrease.)"

Seeing your overall WLAN performance actually drop when you had expected to see a boost is not a selling point. If you're still using 802.11b equipment, for all practical purposes, you'll need to replace it before "upgrading" to 802.11n.