I'm just looking for some validation of my high density wireless design.
Based on a lot of documents I've read I'm trying to get the number of users down to around 10 per AP.
The room in question is a conference / board room that has seating for 42, with the potential for 84 people if it is standing room only. (I know I can't get it down to around 10 people per AP if there are 84 people in there, but I would be assuming they are not on their laptops doing bandwidth intensive things if it is a standing presentation). My design right now is 5 access points (3502). All of them have the 5 GHz radio enabled and the power levels are at the lowest possible. They are all on different channels and are at least 10 feet apart. They are mounted to the ceiling which is at a regular height. I will have the 802.11n protocol enabled but it will be running in mixed mode so legacy clients can still connect. Out of the 5 access points 2 of them will have the 2.4 GHz radio enabled. However I'll be enabling band steering to try and convince the clients to connect to the 5 GHz radio.
Attached are a bunch of screens from my Air Magnet predictive survey. There is a .pdf that shows full 5 Ghz coverage, and another that shows full 2.4 Coverage. And then subsequent screens show each channels coverage (to give a good idea of the cell size of each AP) As for the heat map...anything in gray is below -70dBm. Not sure if I should account for signals that are weaker than that or not. I've read mixed information from various sources.
So is my plan sound, or is it absolutely terrible? Any pointers would be much appreciated.
The room in question is a conference / board room that has seating for 42, with the potential for 84 people if it is standing room only. (I know I can't get it down to around 10 people per AP if there are 84 people in there, but I would be assuming they are not on their laptops doing bandwidth intensive things if it is a standing presentation).
You forgot one culprit: The wireless client.
At the end of the day, it is the wireless client that makes the ultimate (in some cases, dumb ones) decision to join which AP. Wireless clients are known to join the nearest AP and have been observed to be joining the FURTHEST AP in the country.
You could try to encourage your clients to ensure the wireless clients used have their wireless drivers updated. This is particularly important when you are dealing with 802.11n. In the last two/three years the wireless NIC manufacturers have been releasing updated drivers so their products can play harmoniously with 802.11n network.
Just to add to Leo's response maybe is a good idea to disable lower data rates and config a higher mandatory rate like 18,24mbps or higher.
good idea to disable lower data rates and config a higher mandatory rate like 18,24mbps or higher.
I would not consider disabling data rates 12 Mbps because there are some applications (such as Voice CAC protocol) which requires a minimum of 12 Mbps.
I would disable data rates from 1 Mbps to 11 Mbps, 18 Mbps as Mandatory and the rest are supported.
I can see you have put a good deal of thought into your design and I would not say it is terrible, but I would do it quite differently.
I hope that this helps.
Thanks for all the input everyone.
I just installed the access points the other day and did some limited testing.
It looks like for the clients that play nice with the assisted roaming feature (available in 7.4 and higher) the client actually moves to the closest access point very consistently.
Older clients that don't play nice, just stick to the access point they first connect to. I tried disabling all but the highest data rates, but it looks like even at the lowest power settings the signal is still to good no matter where you go in the room and there is no rate shifting. Not a huge deal, as I expect most clients in this room to be mobile devices or at least newer than the laptop I use.
Right now I have no 2.4 enabled in the room, but I plan on enabling on just one of the 5 access points. I have band steering enabled so hopefully most devices will still connect to the 5 GHz but there will still be 2.4 there for any old or miss-configured client. I also enabled the 'client load balance' feature, not sure how that is going to work in real life, I can't really test it myself as I only have two clients at my own personal disposal. Just have to wait until the room fills for the first time I think.
Overall the RF in the room looks good. Because of the power settings being used, when directly underneath an access point you get around -50 dBm, as you move away it quickly drops off to around -65 or -70 but by then you are near another AP with -50 dBm. I'm sure more tuning and configuration will be needed in the coming weeks but I think everything is looking okay right now.