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Old Apr10-09, 06:42 PM                  #1
zetafunction

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an small question about RSA algorithm

on the RSA algorithm

http://en.wikipedia.org/wiki/RSA

why simply we can not choose e=1 or e=2 ??? it would simplify the calculations a lot.
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Old Apr10-09, 07:23 PM                  #2
*-<|:-D=<-<

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Re: an small question about RSA algorithm

Does'nt that go against the purpose of the RSA?

edit: shady comma
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Old Apr10-09, 07:58 PM                  #3
adriank

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Re: an small question about RSA algorithm

If e = 1, then the ciphertext is the same as the plaintext, making the algorithm useless.

It's required that e is coprime to φ(n) = (p - 1)(q - 1), so that there exists d such that ed = 1 mod φ(n). However, if p and q are distinct primes, then one of them is odd, so φ(n) is even. Thus e can't be 2.
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Old Apr11-09, 04:47 AM                  #4
zetafunction

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Re: an small question about RSA algorithm

thanks a lot adriank , nice forum
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