Here’s what Sam had to say…
This one is easy. The answer, contrary to popular belief is not “It Depends”. The answer is very straightforward, easy to understand, and very sane:
The correct number of APs for your design is the minimum number of APs required to meet your stated design criteria.
This means, to have the most optimal (least waste) design, you need to know what you’re designing for. Your design criteria can include all sorts of things such as:
Device type (Handheld Scanners, iPhones, laptops, etc.), areas of perceived special concern (CEOs office, conference rooms, executive admins desk, restrooms, the IT teams office, and other people likely to yell when they can’t see the AP), as well as areas of actual concern (manufacturing lines, dense areas of users, people with critical business dependent needs, restrooms, etc.), as well as anything else that’s going to make you want to add/delete APs at a later date.
Gathering that data upfront is not being pedantic, it’s so that we can design your Wi-Fi and SAVE you money in the process!
It’s a balance between the cost of doing a proper Wi-Fi design and the cost of the assets in the ceiling, cabling costs, switching costs, licensing costs, etc.
Defining precisely what you want upfront allows you to SAVE money in the long run. If you want “extra coverage over at that office/area/restroom”, don’t add it after the fact.
Remember, there is such a thing as too much RF.
Getting all the requirements upfront is a time/resource/materials savings as well as RF hygiene exercise. Our goal should be to optimally deploy as few IT assets to accomplish your stated IT goals (or design requirements).
That “one extra AP” that you added after the fact might have been the money you needed to pay for your proper design in the first place.
In fact, the cost of doing a design is regularly less than the cost of extra investment you spent “because all that proper design nonsense is for the birds”.
Remember, the back and forth of gathering the who/what/when/where of a network's design is not about how many APs you need to put in to make a network work, it’s about how many you can take out and still make everyone happy.
Don’t waste APs. Don’t waste switch ports. Don’t waste labour. Don’t waste your reputation.
Design it right, do it optimally, and document, document, document!
Thanks to WLAN Professionals for this blog post.