I got 8level router and in System tools > System logs I got 15 messages like this in the last hour:
wlan0: A wireless client (A0:6C:EC:BE:7C:2F) was rejected due to access control for 16 times in 5 minutes
What is even more strange, I don't have ANY messages before 1 hour and my router logs events like: wlan0: A wireless client is associated - F8:DB:7F:78:DC:8D. First message when I looked up was about rejecting client due to access control, just at the time what I opened System logs. It look like router start logging messages freshly after my visit to this tab...
UPDATE
My router model is 8level WRT-150A
11 Answer
(A0:6C:EC:BE:7C:2F)That is the MAC address of someone that attempted to connect to your router (wirelessly I'm guessing). It doesn't mean they tried to "hack" it, it just means they selected your SSID when the list of wireless network names appeared. Most routers have a way to make the network name anonymous (not show up). This will make it a little more difficult for people to find it (not impossible) and will stop this alert from showing up.
It is likely they couldn't connect because you enabled security to block or allow connections based on the MAC address.
If you post the router make and model I'll see if I can find a screen shot that shows where to make the changes I'm recommending.
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