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I'm not familiar with algorithm complexity so I'm asking here. I need help determining degital signature complexity, I did some research and all I found is complexity for the D.S.A only:

( ) =(2 ).

( Verification) = (3 ).

I'm using RSA Signature and SHA-2 hush function.

Afaf Matg
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    since encryption and decryption of RSA trapdoor function is of logarithmic bit complexity (with respect to the binary length of the input message), you can expect the same for the RSA digital signature. – 111 Jul 22 '20 at 23:34
  • Thanks for your answer but im hashing the input message then generating the signature – Afaf Matg Jul 22 '20 at 23:50
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    does not change anything (the message m is the h(m)) (sorry not logarithmic but polynomial bit complexity) – 111 Jul 23 '20 at 11:20
  • If you include the normal padding (PKCS#1 / PSS) you have just one operation with a specific key size. The input size in that case doesn't matter, and the padding itself is symmetric (i.e. fast compared to RSA itself). As the hash will be much smaller than a secure RSA key size anyway, the hash size itself really doesn't play any part. – Maarten Bodewes Jul 25 '20 at 20:51

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