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What does the following notation mean in a homomorphic encryption scheme?


What does x and r refer to?

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was closed as 'unclear what you're asking'. Might not be a 'difficult' question, but its very clear – figlesquidge Feb 4 '14 at 20:39

x is the plaintext and r is the randomness.

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ENC (X;r) in (G, q, g) is (g^r, h^r . g^m). Is my interpretation right? – user11706 Jan 30 '14 at 6:16
No, since it uses X instead of m. $\;$ – Ricky Demer Jan 30 '14 at 6:31
ENC (X;r) in (G, q, g) is (g^r, h^r . g^X). How about now? Just want to get it right. Thanks. – user11706 Jan 30 '14 at 6:39
That would be additive ElGamal. $\:$ Two other possibilities are multiplicative ElGamal and Cramer-Shoup. $\;\;\;$ – Ricky Demer Jan 30 '14 at 21:11

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