[phyrrus9]

iOS always requires a passcode on boot, and you can set how often its required (default is always). The passcode itself unlocks the encryption key to the partition holding your data, the phone doesn't ever know it.

In the event you forget the passcode, what recovery options are available?

None. You can wipe the device and start fresh, or you can optionally turn on a secondary encryption system that would allow you to change the passcode using a different passcode remotely.