Reset to factory settings

I had a slightly disconcerting experience today. As I mentioned earlier, we’ve been having some electrical work done, and this morning the guys came by to finish up the last installation and then map out the new circuit breaker configuration. As you might expect, the latter involved a lengthy period of flipping breakers on and off to verify which breaker controlled which appliances, lights, outlets, etc.
At the end of the process, I had to hurry in to work for a meeting, but before leaving I wanted to check that Internet connectivity was OK. I logged in to one of the Macs (the one connected by Ethernet to the Belkin WiFi access point), brought up My!Yahoo!Page!, declared success, and headed off to the office.
This evening my wife asked if everything had gone OK with the electricians: she was unable to get to the Internet from either her PC or her Mac. (Don’t ask….) Both of these systems use WiFi (802.11G)… so what was going on.?
I tried to log in to the Belkin AP from the Ethernet-connected Mac. It failed – “bad password”. After a couple of retries, I found was able to log in without a password. It soon became apparent that somehow (presumably due to all the power cycling) the device had been reset to factory settings. No passwords, default ESSID, no wireless security, no specific MAC restrictions, PST TZ, and wide open to all comers… but unusable by my wife’s systems, because each was configured to use only my ESSID. (There are about 5 neighbours’ wireless networks reachable from different parts of our house, some with no security.)
I re-entered all of the configuration information (yes, I had a back-up copy!) and we’re now back to normal operation. However I’m distinctly uncomfortable with the idea that power cycling the access point could leave my wireless network wide open. That’s not my idea of fail-safe.
(Perhaps it’s an “NSA feature”.)