QUOTE(Wamphyri2b @ Oct 13 2011, 01:14 PM)

Thanks for the more detailed explanation. It just seems to me that if it can be stored on the original, then the full AP data should be able to be stored on the back-up as well. I guess I need to read up on AP security layout more.
I don't know exactly how it works, but looking at the challenge/response data in abgx360, there are 13 AP2.5 challenges. They're based on angles, which range from 0-359 degrees, so that gives you 1,705,817,281,795,782,082,560,000,000,000,000 possible combinations.