Crypt::DH is a Perl implementation of the Diffie-Hellman key exchange system. Diffie-Hellman is an algorithm by which two parties can agree on a shared secret key, known only to them. The secret is negotiated over an insecure network without the two parties ever passing the actual shared secret, or their private keys, between them.
WWW: http://search.cpan.org/dist/Crypt-DH/
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