Re: Just ignore them?
> Is there a valid reason why a wifi network would be sending out deauth frames?
Yes, there may be any number of reasons for asking a client to leave a network.
> Why does an access point accept deauth frames from some random device anyway?
Well technically it's not - it's accepting it from an authenticated client; or in the other direction, the client is accepting it from the AP. The problem is that the packet isn't encrypted or protected and so it's easy to spoof the MAC address(s) involved.
I think it comes down to the old "security wasn't the problem it is now back then" problem, plus the "it's not practical to make a change that would break every existing device". One more example of "if we knew then what we know now then ..."
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