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Is there a general rule of thumb for the # of clients communicating to an AP?

I believe I had seen the # being 25 some where before. If so, is this limitation due mostly to data going thru the single point?
Or is also due to the radios management and control frames?

As a rule of thumb yes I wouldn't go over 25 clients. Again this depends on what data is being transferred across. If it is bandwidth intensive then the number of clients would obviously be lower.

We follow a formula published in a Trapeze Networks whitepaper called "Designing WLANs for Capacity":

(Bandwidth x Number of Users x % Activity Rate per User) /
(%Efficiency x Baseline Association Rate per AP)

You should be able to find it with a seach in the whitepapers section.

Thanks for the bandwith formula.

On my app, the data rate is very low, but I could have up to 100 client
radios on a single AP.

Could this cause a problem? Is it possible to have to much traffic from just managment frames and the small amount of data?

I am seeing some issues with my application starting up correcly.

Regards,

Heck

100 clients per AP? That is a really big number. Even with light applications, I don't think you will have very favorable results. What is the reason for so many clients per AP? If you give us the situation, we may be able to help so that number won't be so high.

We use the " 25 clients per AP " rule of thumb...

If we know the approximate number of clients, with the types of applications they will be using, and the bandwidth expectations, then we will certainly try to design for that..

But usually, especially in high rise office type applications, those numbers are fluid and the clients are not willing to commit to saying who, how much, and how often... so, we resort to the "25 rule" and then monitor after instlalation..

I agree that 100 users is a stretch, even with small requirements.. it only takes a handful of people to subscribe to streaming data (stock quotes, news, etc) or downloading video to pull everyone else down..

Dennis
http://www.myspace.com/denniskline

The clients (up to 100) are on machines and communicate 32 bits of data every .5 seconds.

Could there be too many packets from just management and control frames?

I imagine there would be a lot more traffic if the AP was reset where all the client need to re-associate.


Regards

Are they time sensitive apps?

Well, I'll just come out and say it. Don't do this. 100 clients on an AP is a disaster waiting to happen. Yes there could be too many packets from just managment frames.

Can you give us the situation so we can try to design the system with more AP's? AP's are cheap...

Hi, due to the medium of the access point being half duplex you should not have more than 20 clients on it. i betcha a lot of collisions happening in your ap, overheating and retransmittions.

I agree buy some more aps and perhaps a switch or two and 1 router and bust your speed to the velocity of light !

heckyeah Escribi?3:

Is there a general rule of thumb for the # of clients communicating to an AP?

I believe I had seen the # being 25 some where before. If so, is this limitation due mostly to data going thru the single point?
Or is also due to the radios management and control frames?

The absolute maximum is 2007 which is a limit of AID bits available. Some vendors have lower association limits.

The practical limits depends on what you plan to do. We kept a max of 20 clients per AP.

If you plan to do VOIP for example, the number would be much lower than this. I've seen limit recommendations as low as 7 VOIP associations per AP!

... Jonn Martell, Wireless#, CWNA, CWAP, CWSP, CWNT, PMP
www.martell.ca