I have a tiny understanding problem regarding client-associations in 802.11.
If a client associates to an AP, the AP adds the client to it's association table. How does the standalone AP or the WLAN controller determine the IP-address of the client? The WLC or AP need this AP for local ARP-responding (it's even mandatory for a WLC solution, because ARP packets never travels over the air!!).
Does the WLC gain the clients IP by sniffing traffic or with the local-DHCP relay (or both?!).
An autonomous AP isn't a DHCP-relay - how does an IOS AP learn the IP address of an associated client?
Ok - this was the first part of my question. Now for something different :-)
As soon as the client is associated, it's in the association table of the WLC or IOS-AP. So far so good.
Now, if the radio interface of the client is shut down (no disassoc-frame), my understanding is, that an idle-timer decreases and when it's zero, the client is removed from the list - right?
What's about "silent" client - like a linux host? This thingy is not brabbling like a Windows PC. How does this type of client stay associated? I couldn't find anything in the IEEE 802.11 standard.
So - has the client to send keep-alive packets? I guess so! There's nothing like a probing of the AP.
Hope you can help and thanks in advance!