I HAVE A KEY WHICH IS 1*16 MATRIX. HOW CAN I DETERMINE IT'S BIT SIZE?
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KSSV
2022년 8월 16일
KEY=[0 0 1 0 3 12 8 7 7 8 12 3 0 1 0 0] ;
a = single(KEY) ;
iwant = whos('a')
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Walter Roberson
2022년 8월 16일
편집: Walter Roberson
2022년 8월 16일
Will this key prevent brute force attack
NO it will not prevent brute force attack.
There is no known way of preventing brute force attacks.
There are some famous cases where particular encryption challenges were broken by way of contests that organized thousands of computers on the Internet to keep trying sequential possibilities.
You have 4 bits per entry and 16 entries, for a total of 64 bits. It is accepted that the NSA can brute force 64 bit DES encryption keys, using their custom-built hardware.
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Abderrahim. B
2022년 8월 16일
편집: Abderrahim. B
2022년 8월 16일
Hi!
Try this:
KEY = [0 0 1 0 3 12 8 7 7 8 12 3 0 1 0 0] ;
KEY = single(KEY) ;
% WHOS returns a structure
S = whos("KEY") ;
S.class
% Bit is an eighth of a byte
bitSize = S.bytes * 8
Hope this helps
Walter Roberson
2022년 8월 16일
KEY=[0 0 1 0 3 12 8 7 7 8 12 3 0 1 0 0]
bits_required_per_entry = max( ceil(log2(KEY)) )
However the calculation changes if any entry might be negative.
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