When does density become a problem?
at Ripe65 we installed 17 AP's in the plenary room because there we're 500 ppl with 3 avg 3 devices per person. i'd say with 50ppl per AP density is an issue.
Also depends on which access point you are using
You need to study the number of connected devices that are actively moving data. Some client apps will move significantly more data than others. Just because the device is associated does not mean it is taking bandwidth. Also, keep in mind the number of advertised SSIDs is very important, my practice is no more than 3. You can have more but you need to not advertise them. Advertising takes up a lot of cycles on the APs. With 17 APs you need to decide which ones will advertise 2.4Ghz, cut down the power on those that are using 2.4 so you can minimize co-channel interference. Similarly, on the 5Ghz radios either you can set the power or allow the system to auto adjust channel and power for proper spacing. Remember the Aerohive APs only adjust 6DB at a time. So if you start at 19DB the system will only drop to 13DB on a radio. It almost makes sense to start at a lower power and work your way back up. Everything is about eliminating co-channel interference. Sorry for the long answer, but it should be another two or three pages.
RF Utilization is a key number to keep an eye on. Over 30% starts becoming an issue and over 50% you have problems. Over 70% and it's more or less game over and you need a better design.
I have found that density becomes an issue when:
- The wireless network throughput is adversely affected by transmit retries.
- Stations are being adversely affected by co-channel and adjacent channel contention.
- The access point transmit power is forced down well below the station's transmit power.