Controllerless Networks

We're looking at adding 6 additional access points to a 17000sqft. ballroom for a total of 14 ap's. The goal is to support 50 clients per ap on 5ghz. For 2.4ghz looking at 250 users total for the space.

Do we need to go with directional antennas? (iap-224) or will the iap-225 / 135 work for this install?  ap's are currently mounted at a height of approx 14 - 16ft.

First things first:

If this is open space:

You should:

- Only use 20 mhz channels due to the density

- Consider having the 2.4ghz as air monitors for some of your access points.

- Have no more than 9 APs, because there are only 9 non-overlapping channels in the 5ghz

- Use an AP135 or 225 and if you can mount it on the ceiling (it is good for up to 40 feet or 12 meters).  No need for external access points

- Consider removing the lower rates on your SSIDs so that management and data traffic will consume less airtime (http://community.arubanetworks.com/t5/Unified-Wired-Wireless-Access/High-density-disable-low-data-rates-or-not/m-p/150890/highlight/true#M31991)

Access points propagate very, very well in open space.  If you have density and open space where access points can see each other, every access point you add that repeats a channel already being broadcast will simply decrease performance due to contention.

thanks for your quick response Colin.

Only use 20 mhz channels due to the density

     we are using 20mhz channels

- Consider having the 2.4ghz as air monitors for some of your access points.

      we have 4 of them in monitor mode for 2.4ghz

- Have no more than 9 APs, because there are only 9 non-overlapping channels in the 5ghz

       We are aiming for a device count of 50-60 devices per AP - doing the math it will take 14 aps   to support 700 devices in 5ghz - the ballroom has a 1200 person capacity. Is it a good idea to use or not to use DFS channels?

- Use an AP135 or 225 and if you can mount it on the ceiling (it is good for up to 40 feet or 12 meters).  No need for external access points

   ap's are only at 14-16 feet so we are good there

- Consider removing the lower rates on your SSIDs so that management and data traffic will consume less airtime (http://community.arubanetworks.com/t5/Unified-Wired-Wireless-Access/High-density-disable-low-data-rates-or-not/m-p/150890/highlight/true#M31991)

    Lower have been removed

I've adjusted the Transmit Rates, can the "basic" rates be adjusted in Instant?

The basic rates cannot be adjusted in instant.  You can increase the 5ghz rates all the way up to 24 to reduce utilization even further.   The same with 2.4ghz.  Start with 24 and test it out before deployment with 2.4ghz only and dual-band devices.

Associated clients and active clients are two different things.  Client traffic is very bursty, so you would be fine with that AP number, because not all clients will be transmitting at the same time.  Adding another access point will force you to reuse a channel and increase contention and utilization.  It might even cause a hidden node issue.

Very few mobile devices support or even scan on DFS channels, and the ones that do scan, only scan ocasionally.  Deploying DFS channels in an environment with devices you do not control might "waste" an access point, as a result.

great, thanks for insight Colin