Ideal number of connected clients on one single AP?

[RabbitSF]

Our school is running the 5508 Controller with 3702 APs. Basically one AP for each classroom. There is one teacher keeps complaining the performance of the wifi connection when there are more than 20 iPads or Macbook Airs connected to the wifi running the same thing, such as this Tynker online coding program for kids. 

I have been wondering if this is true that even though the 3702 claimed to support more than 200 connected clients when there are more than 15 clients running the same program it will drag down the AP network performance. If connected clients are running different thing, the AP can handle more clients. Is this conclusion true? If not, what other parameters I need to refer to for checking the performance issue?

Sorry if this sounds like a wifi basic question but I am always curious. Thanks very much in advance!

[Rasika Nayanajith]

Yes, ideally all depend on  client device types/capability and the application bandwidth each user required.

In capacity wise I would not plan for more than 25-30 clients for given AP. 

Have a look on this very useful tool when it comes to capacity planning in WiFi

http://www.revolutionwifi.net/capacity-planner/

200 is the number each Radio support, that does not mean you should allow that many users to connect to single AP

HTH

Rasika

*** Pls rate all useful responses ***

[RabbitSF]

Thanks very much!

I have another side question: How do I check the throughput of one single AP? 

What I want to find out is when, say 20 iPads connected to the classroom AP running something at the same time, what are the Rx/Tx on the AP's interface? Is that possible to find out from the controller GUI or CLI? Or is this something that I should check from the switch interface the AP connected to?

Thanks again!

[mohanak]

Depends on the situation. Cisco recommends no more than 25 clients per WAP, type of traffic also matters, if the type of traffic is mostly emails, web browsing, etc ... then the value can go up to 35 clients per WAP. If the type of traffic is video then the value is around 8 to 10 clients per WAP.