we have a problem, that already occured at two locations:
We installed workgroup bridges (at one location a AP-1242AG connecting to an IOS-AP, at the other location a AP-1131AG connecting to a controller-based WLAN). Behind these workgroup bridges there are devices that talk very little by themselves (about one packet per hour).
So in the IOS-WLAN they are reachable only after pinging the device from the AP to which the WGB is connected. In the controller-based WLAN they are only reachable from the WGB itself, not from the rest of the LAN.
My suspicion is, that these devices disappear from the ARP-/Mac-Address-tables because of the little traffic they send. How can we work around this problem? Static ARP- and/or MAC-Entries? But where to place them, in the core, on the APs?