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I understand the Diffie Hellman key exchange. What I don't understand is the role the server's private key plays in it.

I'm not talking about the servers generated secret. I understand that purpose quite well. I'm talking about the private key associated with the server's certificate/public key.

I understand the role of the servers private key in the RSA key exchange but I don't think the servers private key is needed in the Diffie Hellman key exchange.

If the servers private key isn't needed in the Diffie Hellman key exchange AND I forced all clients to only use the Diffie Hellman key exchange could I, in theory, delete the servers private key for added security?

marked as duplicate by AndrolGenhald, Steffen Ullrich tls Apr 10 at 18:03

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  • It is used to sign the exchange to prove that the server is not an impostor. – AndrolGenhald Apr 10 at 17:22