Wireless networking works so well, who needs wires anymore?
Most of us share a perception of wireless networking that would result in an immediate dismissal of that statement. The sad reality of wireless networking is that when it works well, it usually works well by accident or happenstance: a small number of clients, all with high-quality radios and software, in an interference-free environment communicating with modern equipment strapped to the back of a unicorn sleeping nearby in line of sight.
Wireless networking can work a lot better than it does. Here are some of the things we commonly see wrong with the wireless networks we’re tasked with fixing, and some of the challenges we’re faced with when deploying new networks.
#1 – Wrong channel
The fun thing about radio energy is that the low frequencies penetrate solid objects better. So while the channels in the 5GHz band are wider and can go faster, they don’t travel as far as the 2.4GHz channels. Things like steel, concrete and even leaves on trees get in the way of 5GHz signals. You really should deploy both, since a client that is capable of getting a good 5GHz signal will benefit from its higher bandwidth (which can equal higher speed) and the fact that there are relatively fewer sources of interference in the 5GHz neighborhood (like Bluetooth, cordless phones, baby monitors and microwave ovens, all of which plague 2.4GHz).
#2 – Noisy neighbors nearby
Ever tried to enjoy a nice dinner in a popular restaurant but had to shout at the top of your lungs to be heard? The same is true of wireless networking. In the United States, your 2.4GHz channels need to be 6 channels apart before they don’t overlap and interfere with their neighbors – which means at most, you have 3 channels you can use before they fight with each other to be heard. Your 5GHz airspace is larger but channels are wider, so the maximum number of non-overlapping channels is 23. That sounds great, but it would behoove anyone deploying a wireless infrastructure to fire up a scanner that can show you who’s nearby, and on what channel, before you make decisions about which ones you’ll use.
#3 – Mo’ access points, mo’ problems
So you’ve figured out that wireless networking is a lot like an Ethernet hub, which means that to support more users you need more access points? Great. But do they know about one another? How much power are you broadcasting? The reality is that when you start increasing the number of access points to support more users, you need to use less power, not more, or you create a situation a lot like that noisy neighbor scenario above. Think about the last time you had dinner in a noisy restaurant. Could you have a conversation with your neighbor? What would have helped? Everyone lowering their voice? That’s why you need to ratchet the power down in a multiple-access-point environment. It’s hugely helpful if your multiple access points know about each other and where they’re placed, because smart ones with smart controllers can do that for you.
#4 – Rogue access points
So the wireless is funky – what to do? How about we bring our own access point to work and rebroadcast wireless networking from our cube? This is the wifi equivalent of waiting until the last second to cut in front of the line of traffic waiting to enter the on-ramp. You screw things up for everyone when you do this, and we have seen some horribly broken networks that were the result of a slightly broken network being made far worse by people consuming airspace with their own access points. Good wireless networks discourage this type of behavior by locking these access points out of the network with a containment strategy, essentially prohibiting traffic that originates from them from propagating and sometimes aggressively kicking associated clients from rogue access points. You need a policy regarding rogue access points and you need a strategy for dealing with them.
#5 – Your guest network is a mess
Sure, we like providing access to visitors. There is a right way and a wrong way to do this. The right way involves not having to share a password that winds up being the worst-kept secret in the neighborhood and unlimited access once that password is known. You really should have sane limits on throughput and session length for visitors, with an open network that requires acknowledgment of an acceptable use policy before more data will pass. It’s called a captive portal, and a lot of access points offer it. Some even let you capture useful metrics about the visitors using your wireless network. Want to offer higher speeds to users who check in at your site on Facebook? AirTight and Meraki offer this capability, and there are others.
All in all there are some great tools available that can assess your wireless environment and show you on a floorplan where the access points should be, whether there are rogues and on which channels. We like Ekahau’s and would be happy to do a survey of your site with it. But a lot of problems can be solved by using handheld devices with scanners: I like FarProc’s WiFi Analyzer and have used it to determine why things were horribly broken at client sites and what needed to be done to fix them.
If your wireless network is in need of some love, let us know. Wireless may never be a perfect substitute for a wired connection, but it can probably work better for you than it does now, and we’re here to help you make the right decisions that result in the best wireless experience for your users.