Whether you’re practicing your competitive dive routine or planning out your wireless infrastructure, it’s typically beneficial to know how difficult the attempt is going to be. In the Olympics, the more complex the dive sequence is the more points you get if you pull it off perfectly. String a few good dives together and you’re off to the medal stand. With a well-designed and deployed wireless network, your only reward might be some highly productive users with very few complaints. So while you might not get a gold medal, here are three of the main areas that will help you gauge the degree of difficulty when designing a wireless infrastructure:
1. Devices, devices everywhere….
The first consideration is going to be around devices, not just the number of them, but also the type. So if you have 1,000 Dell laptops that all have exactly the same OS, desktop image, chipsets and drivers, that’s not that hard to plan for. Add in 9,000 more and your degree of difficulty just went up. Now, take those 10,000 devices, but instead of standard issue laptops, they are smart phones, tablets, scanning devices, sensors and Wi-Fi phones. All different manufacturers. All different models. All different versions of OS, many of which may have radically different Wi-Fi performance characteristics (802.11 a/b/g/n/ac, number of streams, data rates, transmit power, receive sensitivity, etc). Your Wi-Fi degree of difficulty is climbing the charts. So don’t just plan for the expected number of devices, be sure to figure in diversity as well. Also keep in mind that in the next couple of years you are going to be expected to support Wi-Fi enabled devices on your network that you haven’t even thought of yet. A Wi-Fi implementation is not a static deployment, but must have a blueprint to expand and change over time as new requirements become apparent.
2. Got Apps?
Here again, you need to look at two different things. First, how complex, or data intensive is the app? Are we talking live streaming interactive HD video, or are we sending a few packets up and down every now and then? Is the app client/server-based, or is the majority of the traffic upstream? Are these apps intended to be used while in motion or stationary? Understanding this will have big impacts on your channel planning, AP placement and even vendor selection.
Once you understand app complexity, you need to look at criticality. How critical is this app to the organization’s well being? If in your office Wi-Fi went down right now, you would be massively inconvenienced, but the world’s not going to come to an end (really, it won’t). But if you were taking orders on your Wi-Fi phone while driving a fork truck across on a warehouse floor, shipping fresh produce across the state and the network went down, you could be jeopardizing your entire business. On a trading floor, even the slightest bit of latency could mean millions of dollars, not to mention what an outage would cost. Even if it’s the simplest app in the world, make sure you understand its broader impact on your organization, and plan for the appropriate degree of app difficulty. It’s also important to understand that you may have Apps of different levels of criticality on the same network. For example, in a hospital, patient guest access may be sharing the same Wi-Fi as life critical devices (IV pumps, heart monitors, etc.). Planning for, recognizing, and prioritization those critical applications and devices should be key in planning your Wi-Fi application support.
3. Running Interference…
Last, but not least, you have to understand the RF environment you are deploying in. Conference rooms are typically easier than dorm rooms that double as tornado shelters. Wi-Fi in a warehouse in the country is easier to lay out than one parked next to an airport (notwithstanding the constantly changing RF environment in warehouses as stock rotates!). A 40 room motel will probably be just a touch less pre-work than what is needed for a cruise ship. And let’s not forget about rogue AP’s, microwave ovens, cordless phones, Bluetooth devices, wireless video cameras, outdoor microwave links, wireless game controllers, Zigbee devices, fluorescent lights, WiMAX, etc etc… that can all impact Wi-Fi performance.
End users are convinced that Wi-Fi just magically happens and should work like it does from their couch at home. What they don’t understand is that their single AP deployment surrounded by drywall and serving six devices is a “belly flop” on the difficulty scale. Your organization, let it be a school, university, hospital or enterprise, might have an environment “degree of difficulty” that looks more like the Triple Lindy (full credit to Rodney Dangerfield). Plan accordingly.