concurrent user and data rate per user calculation
06-28-2019 03:26 AM
customer asked me the calculation.
How many concurrent users under below situaiton?
- 2.4GHz only
- 1 x AP only
- 20MHz or 40MHz channel width
- 1G internet bandwidth
- assume each user consumes 5Mbps
Re: concurrent user and data rate per user calculation
07-10-2019 03:48 AM
This question is not so easy to answer. It is deprecated to use 40MHz channels on 2.4GHz, and you probably won't find a client that can do 4x4:4 on 2.4GHz, normally not each client will draw the same amount of data, so it will be a very theoretical exercise.
If you really want to do the math, assuming 4 streams on a 40MHz channel on 802.11n (as ac is not officially supported on 2.4), you can look up on mcsindex.com that with the maximum MCS (31 which uses 64-QAM 5/6), there will be a link speed of 600 Mbps. I think on a good day under lab conditions, and no interference or other wifi networks around, you may get 400Mbps TCP throughput out of that which divided by 5 Mbps will give you 80 clients.
Again, this calculation does not give you anything as the scenario is far from reality.
If you receive this kind of question, it's probably time to get a good wireless engineer on site that can explain how WiFi works, get the real design requirements and expectations on the table and create a design around that.
If you have urgent issues, please contact your Aruba partner or Aruba TAC (click for contact details).