CWDP and Voice over Wi-Fi Best Practice
Last Post: December 7, 2015:
I've recently just zipped through one of the CWDP practice tests and I have a query regarding one of the questions - and the explanation given for the correct answer.
In short, it suggests that best practice is to provide coverage with at least 2 APs providing sig' strength of -6x dBm.
IMO this requirement is often very counter productive and requires large numbers of APs to be placed which have a detrimental effect on capacity through CCI - as well as being expensive.
To illustrate this, imagine the scenario:-
- You need to cover a small room - maybe 15 x 15 ft in size. It's got concrete walls and has a single door leading onto a long corridor.
- To meet the 2 x -6x dBm spec you would need to put 2 APs in that room.
- Replicate this across a large facility and suddenly you have many, many extra APs.
- With only a single door, you can only go out into a corridor which - if covered correctly with a simple -67dBm coverage model - would have an AP available to facilitate roaming adequately.
So - is not a blanket 2 x APs at -6x dBm model often overkill?
I've expanded upon this in a blog post over at my weaponsgradewifi blog....
The -6x power level and overlap are obviously considerations for roaming, A room as you describe is not representative of a space where you would apply all of the recommendation.