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    Author Topic: Pollard's kangaroo ECDLP solver  (Read 62697 times)
    unclevito
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    July 04, 2021, 08:15:34 PM
     #1921

    Just FYI, for my 2 cents, if you know the range a key lies in, or want to gamble and take a chance where you think the key may lie, then I think subtraction is better.

    Like I said a few posts back; we will take #120 puzzle for example. The private key can only start with 1 of 8 possibilities: 8, 9, A, B, C, D, E, F

    Let's say you think it starts with C. You can then take the pubkey and subtract by C00000000000000000000000000000. Let us now say for example purposes the private key is:
    C23BD97E765A75F0D6D4A6C6B67221.

    So for your search range, after subtracting the C000....would be 0:FFFFFFFFFFFFFFFFFFFFFFFFFFFFF

    By subtracting, you went from a search range of 2^120 to 2^116; 16 times smaller the original search range. BUT if you guessed wrong and the key does not start with C, then you will not find the key.

    Staying with the same example, if you thought it started with C, D, E, or F and you subtracted by C000....then you could search the range of:
    0:3FFFFFFFFFFFFFFFFFFFFFFFFFFFFF, and now you've went from 2^120 down to 2^117, 8 times smaller. BUT again, if the key does not start with C, D, E, or F, you won't find the key.

    Dividing is fascinating because in your mind you see a much smaller search range, BUT the amount of pubkeys you have to search GROWS the smaller you cut the search range.

    So I understand you subtract C00000000000000000000000000000 from 02CEB6CBBCDBDF5EF7150682150F4CE2C6F4807B349827DCDBDD1F2EFA885A2630 the public key for 120 and for example if you wanted to search F then you would subtract F00000000000000000000000000000 from 120 public key? and then search the same range 0:FFFFFFFFFFFFFFFFFFFFFFFFFFFFF
    Correct.
    i was thinking last night that we treat each keyspace as if they were  separated by a wall but they are not so i measured the distance between 115 and the center of 60 then reduced the public key of 115 by that amount. i hit the 115 public key ( i scanned a thru f on 60 and about one hour later I got a hit. Key found privkey fc07a1825367bbc
    Publickey 0242257a130fe109c25c2ca6c60af60e5849305f77370401299b63da2094ec0297 and the addition  + 31464123230573851029232324144930570 . Trying it on 120 but so far no luck. i wish I had this kind of luck on 120 or the powerball lol. I have a image of the hit but don't think I can post it. The addition goes to the private key found
    Awesome!

    So the center of 60, which was what, in your calculation? so you took 115 - minus middle of 60 = x and subtracted x from original 115 pubkey, right?
    And then you did a search in the 2^60 range?
    Yes but i got so excited i overwrote the calculations wanting to try 120 lol. I used a python script to reduce it though
     

    These are the subtraction points i tried but I don't know which one hit and not sure if they were for 115 or 120. i do remember the center of 60 used was c00000000000000
    subtraction points 60
    7FFFFFFFFFFFFFF400000000000000  
    08FFFFFFFFFFFFFF400000000000000
    09FFFFFFFFFFFFFF400000000000000
    0AFFFFFFFFFFFFFF400000000000000
    0BFFFFFFFFFFFFFF400000000000000
    0CFFFFFFFFFFFFFF400000000000000
    0DFFFFFFFFFFFFFF400000000000000
    0EFFFFFFFFFFFFFF400000000000000
    0FFFFFFFFFFFFFFF400000000000000
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