Re: RSA moduli sizes

K. Jennings ha scritto:
However, does it make any difference, from a security point of view, if the most significant bit of the modulus is zero?

Well, if you're after - say - a 1024-bit modulus, which means a 1024-bit key, and the MSB happens to be zero, then that's not a 1024-bit key.

It also simplify things to have the MSB set in the modulus N and clear in the message M you encrypt / sign, because that ensures it's always M < N and the remaining 1023 bit pattern of M can be anything.

Regards,
Giuliano Bertoletti
.

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