Hi James, I am still not sure why you need homomorphism in this case. What is the benefit of using homomorphism to porticor's customer, for example?
Saqib On Sun, Feb 19, 2012 at 1:34 PM, James A. Donald <[email protected]> wrote: > On 2012-02-20 2:08 AM, Florian Weimer wrote: >>> Can somebody explain me how this so-called Homomorphic split-key >>> encryption works? > > Homomorphic means you combine the keys without finding out the key that you > are combining - Everyone gives you an encrypted copy of their key fragment, > and when you are done, you have an encrypted copy of the combined key. > > > >> Isn't this just a protocal which performs a cryptographic primitive >> using split key material, without actually recombining the keys? >> (Traditional Shamir secret sharing needs a trust party for key >> recombination.) >> >> If yes, you might want to look for "RSA Threshold Cryptography" and >> similar work. > > My understanding is that RSA Threshold always requires a "trusted" party, > which makes it useless. If you have a party that is actually trusted, just > let him count the votes or whatever. The cryptography does not do you any > good. > > The only protocol that I am aware of that performs cryptographic operations > on a split key with needing a trusted party, uses Gap Diffie Hellman > groups. > > All known Gap Diffie Hellman Groups consist of an elliptic curve which > supports a bilinear pairing from the curve to integers modulo some large > prime. > > _______________________________________________ > cryptography mailing list > [email protected] > http://lists.randombit.net/mailman/listinfo/cryptography _______________________________________________ cryptography mailing list [email protected] http://lists.randombit.net/mailman/listinfo/cryptography
