802.11n Momentum Mounts
Seven years in the making, the IEEE-802.11n wireless LAN standard is finally complete. But there’s greater significance than the accomplishment itself for SMBs and WLAN technology.
By Alan R. Frank
The IEEE’s ratification of the 802.11n WLAN standard last fall is an important milestone, says Mike Tennefoss, who heads strategic marketing for WLAN vendor Aruba Networks Inc., based in Sunnyvale, Calif. Tennefoss feels that while many customers were willing to move ahead with Wi-Fi-certified Draft 2.0 products, a lot of larger businesses were holding out for ratification before making any purchasing decisions.
“There was always the risk—albeit a very small one—that there wouldn’t be backward compatibility,” Tennefoss observes. He counts banking and insurance among the verticals that held back. “Now,” he says, “the entire market is satisfied that we have not only backward compatibility, but we have finished work—not a work in progress.”
11n’s 5x or more improvement in data throughput (compared with 802.11g) and expanded, more uniform RF signal coverage—both courtesy of 11n’s use of multiple input/multiple output (MIMO)—significantly alter the age-old wired vs. wireless equation.
What we’re witnessing, says Adam Conway, vice president of product management for WLAN vendor Aerohive Networks Inc., Santa Clara, Calif., is the transition of WLANs from being “convenience networks” serving conference rooms and guests to “a lot more mobile applications, to voice, to being mission-critical, and—with 11n—the possibility of removing wires from the business.”
In a September 2009 report, Burton Group analyst Paul DeBeasi goes so far as to write that 802.11n “represents the beginning of the end for wired Ethernet as the dominant local area network access technology in the enterprise.”
But Greg Beach, director of product management for Cisco Systems Inc.’s wireless networking business unit, wouldn’t count Ethernet out anytime soon. “Wireless is definitely going more mainstream for user access,” he notes. “But we think you’ll see, down the road, a mix of wired and wireless [in the access network], dependent on the user requirements and application requirements.”
MEASURING THE MARKET
With IEEE 802.11n officially a standard, what does that mean to prospects for 11n-based Wi-Fi equipment in the marketplace? Analyst firm ABI Research reports that 11n-based WLAN access point (AP) shipments in 2009 were up nearly 44 percent over the previous year. True, that report focused primarily on the high-volume consumer and SOHO markets, but the smallest businesses—those that can be adequately served by a single AP or wireless router—often purchase from among consumer/SOHO WLAN products.
Moreover, the report went on to note what the firm considered to be “particularly strong demand for enterprise WLAN 802.11n-based access points,” estimating that enterprise 11n AP shipments reached half a million units last year. (Larger SMBs typically deploy this class of products.)
Philip Solis, practice director for wireless connectivity at ABI, says: “802.11n will dominate in the consumer market in 2011 and in the enterprise market in 2012.” In 2014, it will comprise 97 percent of enterprise AP shipments and 100 percent of consumer AP shipments, he projects.
The firm reports that 7.8 million 11n consumer/SOHO APs were shipped in 2008, a number that ABI expects to reach 32.2 million units this year.
WHAT’S INSIDE?
What’s in the finished standard that wasn’t in Draft 2.0? There are a number of optional techniques that further raise throughput, but perhaps the most significant are the use of three-spatial stream and four-spatial stream MIMO. (Draft 2.0 had defined the specifications for two-spatial stream MIMO.) Thus, the theoretical maximum data rate (at the physical layer) rises from 300 Mbps for two-stream MIMO to 450 Mbps and 600 Mbps for three-stream and four-stream MIMO, respectively. Additional technologies include space-time block coding, a shorter guard interval, transmit packet aggregation, and coexistence mechanisms for 40-MHz operation in the 2.4-GHz band.
Of course, just because there is a standard that defines up to four spatial streams doesn’t mean there are products. There’s always the development time for the chip makers to evolve three- and four-stream Wi-Fi chipsets and for WLAN vendors to design them into products.
And not everyone is convinced there’s a pressing need at this time. Kelly Davis-Felner, marketing director for the Wi-Fi Alliance, says: “It seems—and I’m being very general here—that most of the three- and four-stream products are going to be very consumer electronics and digital home–focused.” That’s a point that ABI’s Solis agrees with, saying that the driver will be people who want to stream high-definition video.
“I would expect that in the next 12 months we’ll see a migration to three-spatial stream products in the enterprise,” says Aerohive’s Conway. However, “the move from two-stream 11n to three spatial streams is a much smaller [50 percent] jump in performance than that from 11g to two-stream 11n [500 percent].”
WIDER HORIZONS
Bob Bruce, Aruba vice president of worldwide channel operations, notes that even before 11n, wireless LANs (of the 11a/b/g variety) had been considered a necessity in a number of verticals—and he counts education, healthcare, retail, and distribution among them. The impact of 11n, he says, is that it “has widened that area of applicability to encompass virtually all of the enterprise.”
“There’s a huge opportunity for 11n in the SMB, with Wi-Fi moving from ‘convenience’ networks to becoming a viable Ethernet replacement in many environments,” says Stephen Philip, vice president of corporate and product marketing for Aerohive. “And we think it’s going to happen much faster in small and medium businesses than in traditional enterprises.”
ALAN R. FRANK (alanfrank@embarqmail.com) is a networking consultant and freelance writer covering networking and communications technologies.
