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Old 18th February 2007, 16:47   #19  |  Link
arnezami
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Join Date: Sep 2006
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Quote:
Originally Posted by FoxDisc View Post
@arnezami - Excellent work!

At the present time, all discs use the same Processing Key
(Parking Space). Unless the same Processing Key (which is just a number) appears on different subtrees (levels of the parking garage), this means that the Processing Key in current use is on the largest master tree (the only one that all devices/trucks can access/drive on) No device (truck) can get to a Processing Key that is in its own upward chain. Yet every Processing Key in the master tree is in some (possible) device's upward chain. I'm guessing that there is a special spot in use right now at the base of the master tree that holds the current Processing Key/Parking space instead of a device/truck. All other devices in the tree can get to that spot, except the device/truck that starts there (The truck would already be there, but I thought I understood that a device could not calculate it's own single node Processing Key, as well as all the upward processing keys in its chain to the root.)

I understand the "instructions" in the MKB define the "path" to get to the Processing Key, by using ones to go right and zeros to go left when tracing from the top (perhaps I have it reversed - don't recall). Can you confirm where the current Processing Key is located on the tree/parking level and whether it's down low near the base of the master tree/trucks or up higher in the tree? Is it over on the far lower right or left of the master tree?
The current Processing Key is in the far lower left of the tree used. This tree is the first tree (out of 513 I believe, I haven't analyzed yet why it isn't 512) which is why the first C-value is used. In other words: the largest tree isn't the 31 nodes high tree (which would be the truely root tree) but several floors higher. AACS simply doesn't use the trees with 31-23 nodes high. Which is why the lowest floor (for AACS) is still didived in approx 500 trees I believe.

If you open your MKBROM.AACS and take/print the docs you can see the all this in the Explicit Subset Difference Record. It takes a little effort but the number 17h (=23d) is already telling. Maybe we should make an MKB file reader or something which graphically shows you which sub-trees are used (and thus have a C-value) and what their "shape" is (the position of the C-values in the trees creating subset-differences). Would be cool and informative in the future (when they start revoking).

There could also be some slight difference in the way it works (at the very lower end) and how I pictured it. But these details will eventually be ironed out .

Last edited by arnezami; 18th February 2007 at 16:54.
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