I’ve been involved in a number of planning meetings for IT infrastructure refreshes – servers, storage, WAN, networking, wireless, you name it. Most of the time the requirements are more or less well-defined and well thought out… number of hosts, exact processors, memory requirements, connectivity to the storage arrays, VLAN assignments, and so on. All the I’s have been dotted and the T’s have been thoroughly crossed. But there’s always one noticeable outlier – the wireless network.
“Oh and… maybe 10 APs? Maybe 12 just to be safe.”
It’s 2017 and we can simulate just about everything. Why are we still using primitive thumb based rules for the wireless network?
- If you guess too high, you’re out a sizeable chunk of money and you may not even get additional bandwidth.
- If you guess too low, you’re going to have slow/dead zones. And good luck getting management to not only buy more APs in a separate purchase, but also to pay for the cabling.
- CCI is a real thing. Adding more APs does not necessarily add bandwidth. It’s the laws of physics!
- Just “cranking up the coverage” doesn’t always work either. Client radios are only so strong, and the conversation has to flow in both directions.
- It’s ill advised to go with the “low capacity” model and just throw extra APs up in high density areas as needed, again due to the laws of physics. Be sure to choose beefy APs for the auditoriums, gymnasiums, and so on.
- One AP per room is not a valid design principle.
- A design will help you determine how to balance building for 5GHz coverage while not creating a trainwreck in the 2.4GHz spectrum (hint: spectrum analysis isn’t a bad thing to have running in the background)
- Wireless is how we connect now. If your wireless performs poorly, it doesn’t matter how slick a datacenter you’ve built to serve up the applications, people will only remember that it didn’t load properly.
There are programs available that can fully simulate wireless propagation through all kinds of floor plans and allow you to effectively preview the performance of your wireless network, all from the comfort of your own home. While it’s still advised to take some onsite measurements in complicated deployments, a predictive survey will give you a much better starting point than the infamous “1 AP per room” design.
I’ve been using Ekahau Pro myself and it’s been a life saver.
You probably won’t be refreshing the wireless infrastructure for another five years – why not ensure that it’s going to work well?
Thanks for reading this slapdash semi early morning rant. And no, I am not being compensated by Ekahau for this blog.