The Thrill Of 802.11n

Remember back to when you got your first big-kid bike, with adjustable gears and big wheels? Remember going down a sizable hill for the first time on those new wheels, and how you just knew life would never be the same? Migrating your wireless network to 802.11n rekindles those memories, and when you realize exactly what you've got in the latest wireless standard, everything that came before it seems suddenly tame by comparison.

The production network that I support is still legacy 802.11a/g, but I've recently had opportunities to set up 11n networks and to kick tires in test on product sets from Aruba, BlueSocket, Cisco and Meraki. I've also just pulled the trigger on the start of upgrading my 2,500 access point Cisco WLAN to 11n. Regardless of who's hardware you are playing with, the numbers game behind 802.11n brings an element of excitement to the party when you start seeing the results in action.

The easy thrill comes in the form of data rate, as reported by the clients themselves. An a/g network can deliver a rate of 54 Mbps at best, in either band. Compared to the golden days of 802.11b where 11 Mbps was king, 54 Mbps is arguably impressive. But the first time your client reports that it is running at 300 Mbps, you can't help but stare at the digits for a few seconds while your mind processes it. Wireless networking is a management-heavy technology compared to 802.3-based wired Ethernet; between security protocols and collision-avoidance mechanisms, true throughput that is between one-third and half of the stated data rate are pretty typical. But even so, half of 300 Mbps still beats Fast Ethernet by half-again. This is powerful stuff when weighed against the 20-25 Mbps of true throughput delivered by a/g networks on a good day.

Ah, but there's more to get jazzed about. Throughput is impressive, but networking history is full of examples where clients want the fastest link they can get and then never utilize more than a small fraction of their new and bigger pipe. As a wireless network engineer, architect and administrator, my heart skips a beat when I think of the perhaps non-obvious benefits of 11n- including "better" radio cells that include higher data rates farther towards the edge of each cell. Even in densely covered wireless environments, we've been fighting physics since the beginning of WLANs and bemoaning how multi-path signals (multiple images of same signal, varying in fidelity and strength, hitting receive antennas at the same time) can cause performance degradation for wireless clients. 11n embraces multi-path, and turns liability into advantage with MIMO (multiple in, multiple out) smart antenna systems that make use of each multi-path image and turn the combined result into something wonderful. These sorts of gains may be imperceptible to the average user, but are the stuff of higher-performing wireless environments and reduced help desk ticket fodder.

Given that more organizations are seriously moving to wireless and at least partially cutting the cord on an increasing scale, 802.11n is easy to get revved up over.