I currently have 4 controllers with multiple vlans configure for one ssid.The vlans are group by building and each vlan is a /24 network. I have been asked to create one vlan per controller with a /21 network.I am worried about the size of this network and impact it will have on my wireless users.Do I have an issue with possible packet collision in wireless?Also I currently don’t allow wireless users, via the check box on the controller, to talk to each other will this stop the broadcast issues with such a large network?
We are talking about different kind of broadcasts/collission:
RF: Each AP talks at a certain channel to all associated clients. Only one can talk at the same time. Thats why it´s not a good idea to have too many clients per AP.
IP: An IP-network is a IP broadcast-domain. That means that clients that sends broadcasts (l2 or l3) talks to all other devices within the same broadcast-domain. However, when talking about Cisco WLC-solution the IP-network size is irrellevant as long as the wlc is configured the right way. You can configure the system to not allow client to client-traffic as well as not allowing broadcasts. That´s why you can have thousands of clients in the same IP-network when using Ciscos leightweight wireless solution.