How 802.11n Will Revolutionize Connectivity
Grant Moerschel and InformationWeek
January 25, 2010
Eleven drafts and 73 months. That's what it took to bring the final, ratified 802.11n standard to a network near you. Fortunately, it's worth the wait--11n is a quantum leap forward that, in our estimation, will change the WLAN game altogether. The Wi-Fi Alliance says 802.11n equipment will have five times the throughput and twice the range of legacy Wi-Fi gear; speeds are currently at 300 Mbps, with 450-Mbps and 600-Mbps systems on the horizon. The specification uses radio and antenna technologies in clever ways, while still providing support for legacy 802.11a/b/g devices.
Quite clearly, the target for 802.11n is to supplant wired switches. Still, the 779 business technology professionals responding to our InformationWeek Analytics survey on wireless LANs have reservations about using any WLAN as the main means of connecting end users to the network. Top among their worries: reliability (53%), speed and performance (50%), data security (48%), and consistency of experience (41%). There's also competition for the hearts and minds of CIOs who are working toward a more mobile workforce. Carriers like AT&T and Verizon have used the delay in delivering 11n to their advantage by building out their 3G networks. Cash-strapped IT groups moving from desktops to a mix of laptops, netbooks, and smartphones and seeking fast, ubiquitous mobility may well ask: Why spend money on 11n gear? Why not just leave the legacy WLAN in place in conference rooms for visitors and get data plans for employees?
These are legitimate questions that WLAN vendors will need to answer. On their side is the high cost of 3G data plans, which can run to $60 per month. Stripped-down $35 netbook deals are generally restricted to 200 MB or so of data per month. And you're depending on the public Internet to service enterprise end users who expect reliability comparable with wired Ethernet and will give IT an earful if they don't get it. They're also accustomed to, and often legitimately need, more bandwidth than 3G--or, for that matter, 802.11a/b/g--services can deliver.
"We are looking at a dual-mode strategy for 11n interior and carrier-based 3G/4G exterior," says Scott Ksander, executive director of IT network and security for Purdue University, which has about 30,000 unique wireless users per month. Ksander says WLAN usage is setting records this semester, with about 10,000 students and staff accessing the system per day. "Interior and office environments will require greater--near 100-Mbps wire speed--wireless bandwidth for the foreseeable future," he says. "The timeline between 11n work and 4G still looks to be a good fit for us. We certainly want 'ubiquitous,' but even 4G is not going to provide sufficient bandwidth for hour-to-hour standard office usage."
Ksander says Purdue's Cisco 11n deployment is providing the expected bandwidth and benefits, but he has his eye on 4G developments. For most organizations, the answer will be a mix of wired ports, 11n WLAN access, and more expensive 3G plans for the subset of employees who need them.