How can i know how many simultany users does a AP support?
If you are looking for the theoretical Maximum number of users per AP (most experts would recommend 15 to 20 Max);
Here is a cisco doc that relates to this question;
Q. How many clients can associate to the AP?
A. The AP has the physical capacity to handle 2048 MAC addresses. However, because the AP is a shared medium and acts as a wireless hub, the performance of each user decreases as the number of users increases on an individual AP. Ideally, not more than 24 clients should associate with the AP because the throughput of the AP is reduced with each client that associates to the AP.
From this Q&A doc;
If you are looking at allowing only so many users to associate to an AP at one time you can use the max-Associations command.
This example shows how to:
Name an SSID
Configure the SSID for RADIUS accounting
Set the maximum number of client devices that can associate using this SSID to 15
Assign the SSID to a VLAN
AP# configure terminal
AP(config)# interface dot11radio 0
AP(config-if)# ssid batman
AP(config-ssid)# accounting accounting-method-list
AP(config-ssid)# max-associations 15
AP(config-ssid)# vlan 3762
From this doc;
If you are trying to find out how many users are associated to an AP, this example shows how to display all client devices associated with the access point:
AP# show dot11 associations client
Hope this helps!