Reality Check: A three step program to an 802.11n world

Editor’s Note: Welcome to our weekly Reality Check column. We’ve gathered a group of visionaries and veterans in the mobile industry to give their insights into the marketplace.
The final ratification of 802.11n arrived with a whimper. The real bang happened when the Draft 2.0 pre-standard was approved with a promise of backward compatibility with the ratified version, whenever that ultimately happened. That promise allayed the concerns of all but the largest enterprises, and the floodgates poured forth a wide range of 802.11n Draft 2.0 Wi-Fi infrastructure and client products. With the final ratification of the standard, large enterprises have started climbing on the 802.11n bandwagon, too.
Now what? The availability of a standards-based technology that offers better performance than fast Ethernet – and mobility unavailable from any wired network – changes the networking landscape. It’s tantalizing to consider what a wireless edge will bring us: Wi-Fi based desk phones that can be moved and used anywhere; streaming multi-channel broadcast video that can be received wirelessly campus-wide; wireless video projectors that do away with unsightly Ethernet cabling.
Then reality sets in – these applications require more than a fast physical layer. The more applications that are run on a wireless network, and the more business-critical 802.11n Wi-Fi becomes, the greater the need for physical security, quality-of-service assurances, and survivability. Think about the evolution of cordless phones. When they first became available we simply switched to a wired phone if reception was poor. As cordless phones became ingrained into our daily lives, we had to build in channel management to prevent contention from the neighbors’ phones, security to protect privacy, and contingency mechanisms so we could still access a phone line if the power failed.
Most wired networks have no encryption enabled yet we (mistakenly) trust them because we believe we’re in control of the signal path. We have no such illusions about wireless – we know it can and likely will be intercepted. The more applications we push over Wi-Fi, and the greater the financial/business/personal exposure we sustain from the compromise of those applications, the greater the incentive for bad guys to try to crack it. So step one in an 802.11n world is to ensure that those high-speed devices can be corralled by WPA2, 802.1x, policy enforcement firewalling, and access control.
Filibustering is a time honored tradition in political circles, a tool used by crafty elected officials to bend the political process to their will. Filibustering by chatty or exceptionally slow Wi-Fi clients is anathema to network performance, and can bring applications to a halt. The more latency-sensitive voice, video, and telemetry applications that migrate to 802.11n, the greater the need for QoS mechanisms to ensure that those applications have the requisite channel access, bandwidth, and airtime to work optimally.
Step two is to ensure that the 802.11n network appears to be an exclusive pipe from the perspective of the applications – no impediments, no hindrances. Policy enforcement firewalls, airtime fairness algorithms, load-balancing, and even the ability to steer devices to quieter channels are all tools that can and should all be brought to bear to ensure that applications running on a wireless network obtain the quality of service they require.
To give a real-world analogy, several years ago I worked on a fly-by-light project in which the mechanical thrust controls in a jet aircraft were to be replaced by a fiber optic control system to reduce the weight of the aircraft. The goal was to enable the plane to take-off and land on shorter runways. To withstand dual points of failure, and provide reliability equal to or better than the redundant mechanical system it was replacing, a triple redundant self-healing fiber optic network was used. In the real world things break, accidents happen – networks need to include recovery mechanisms.
Step three is a survivability plan. Access points, Power over Ethernet injectors, switches all can fail. Designing an 802.11n network without enabling adjacent access points to fill in coverage gaps caused by a failed AP, or depending on an “array” that packs lots of 802.11n radios into a single enclosure without a redundant back-up, is worse than false economy. It puts the business at risk. One outage and the money saved by using a cheap design, instead of a survivable one, will pale in comparison to the impact on your business.
802.11n is going to change the way we build and use data, voice, video, and telemetry applications. But the technology is the beginning of the beginning of a solution – it is not itself the solution. When considering an 802.11n network, look not at what 802.11n can do in theory, but what steps you and the vendor must take to make 802.11n reach its full potential in the real world.
Michael Tennefoss has more than 25 years of product management and marketing experience in the networking and controls industries. Tennefoss joined Aruba in 2007, and is responsible for Aruba’s strategic marketing group including product marketing, press and analyst relations, and training. Prior to joining Aruba he was the VP of Marketing at Meru Networks. Previous to Meru Tennefoss was the VP of Marketing at Echelon Corp., a leader in control networking and smart grid technologies, where he worked for 14 years. He also served as Director of Monitoring Systems at ETP, a manufacturer of high security encryption and communication systems, which was subsequently acquired by Stellar Systems, a Division of Wackenhut Corp. Tennefoss started his business career as VPof Marketing at Vindicator Corp., a leader in high security monitoring systems that was subsequently acquired by Honeywell. Tennefoss has dual degrees from the University of California, Davis, and an M.A.from the University of Minnesota.