Did my Android tablet unencrypt itself?

[Deozaan]

I enabled full, system-wide encryption on my tablet about a year ago in an attempt to keep my data more secure. This has the side-effect of requiring me to enter my pattern before the device will even boot up. I don't often restart my tablet, so that never really bothered me.

But the past few times I have restarted my tablet I noticed that it didn't prompt me to enter my pattern before booting up into the OS. I dismissed it as me doing things by muscle memory and just not remembering having entered my pattern at the prompt. But after having that feeling like it wasn't asking me for the past several times, I finally decided to conscientiously restart it to find out if it was in fact asking me for my pattern to unlock the device.

It is no longer asking me for my pattern to unlock the device before it will boot into the OS. The question now is, why not? And the follow up questions: What does this mean about the device's encryption? Did it unencrypt itself? Did it just stop asking to unlock at boot because it asks again at the OS login screen?

[Ath]

Make and model, Android version?

[Shades]

looks to me like an update of any kind of program or even android itself reverted to the default safety measure for login...meaning none. Nice, eh? All those applications demanding access to parts of the OS that aren't (or hardly) related to the functionality of the software.

Anyway, this is just the login procedure. At least in my limited experiences with android it is. Now if you used a different program to encrypt whatever content on your tablet, I don't think you should be worried.

However, if you want to test it properly, transfer any random encrypted file from your tablet to a location (PC/Mac/tablet/whatever) that hasn't been exposed in any way or form with the encryption scheme you used on your tablet. If you can read the file without problem on that location, assume that all your data on your tablet isn't encrypted. Perhaps it never was to begin with.

Without using digital certificates (PKI or better) and/or software such as TrueCrypt (don't know if an equivalent exists for android) I don't consider anything really encrypted.

[Deozaan]

Make and model, Android version?

Asus Nexus 7 2013 (flo/razor) running the latest vanilla Android 6.0.1 with March 1, 2016 security patch (which may have been when the "unencryption" occurred).

Checking the security section in the settings says that my device is encrypted.

So, to clarify, I used to have to enter my pattern just to boot the device, then enter it (my pattern) again to login to the OS. Now it boots to the OS login screen without requiring my pattern, but still requires my pattern to login to the OS (which is how it worked before I encrypted the device).