I am learning about Elliptic curve scalar multiplications and I am on NAF, and I am trying to figure out the concept.
What I understand is if I have K=27
with using NAF the binary looks like this 100-10-1
then the scalar multiplication process like this: 2(2(2(2(2P))-P))-P
which is 5DBL and 2ADD.
My questions is if want to scalar K=27
it means the steps like this:
1- 2P (0 bit)
2- 4P (0 bit)
3- 8P-P=7P (-1 bit)
4- 14P (0 bit)
5- 28P-P=27P (-1 bit)
My issue is how can I calculate 28P
then minus one P
and my group only 27P
my group is like this:
1 3 10
2 7 12
3 19 5
4 17 3
5 9 16
6 12 4
7 11 3
8 13 16
9 0 1
10 6 4
11 18 20
12 5 4
13 1 7
14 4 0
15 1 16
16 5 19
17 18 3
18 6 19
19 0 22
20 13 7
21 11 20
22 12 19
23 9 7
24 17 20
25 19 18
26 7 11
27 3 13
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