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I have seen so many references all over the internet on how to implement ECDSA from the sender's point of view. That is the encryption of the message by signing it and it's validation. I did not find any implementation for the same from the receiver's point of view. I have one reference for the decryption process mentioned here. But I find it hard to understand. I have seen this. It is easily implemented in C#, but only signing is done. Can anyone show me any example of decrypting ECDSA from receiver's side implemented in C#?

Shilps
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    ECDSA refers to the Elliptic Curve Digital *Signature* Algorithm. As the name implies, it is about signatures, not encryption. It's true that an ECDSA keypair can be used for ECDH, but it's best to firstly think of them as distinct and secondly not to use the [same keypair for both uses](https://stackoverflow.com/a/4970640/238704). – President James K. Polk Jul 07 '20 at 15:58
  • For signing and encryption that would be hard to do that anyway, as the receiver and the sender would need the same private key - and there is no such thing as a shared private key :) – Maarten Bodewes Jul 07 '20 at 22:59
  • I understand that the k value needs to be different everytime. And that a shared key pair is required. Then how is cryptocurrency transaction implemented? The same private key is used to send and receive the funds. How do they share the private key? @MaartenBodewes – Shilps Jul 09 '20 at 02:54
  • "That is the encryption of the message by signing it and it's validation." I think that this is simply confusion. Signature generation is **not** signing with a private key. Transactions need to be put in the ledger, not encrypted. Usually this only comes up [with RSA](https://crypto.stackexchange.com/q/15997/1172) as ECDSA is just signature generation; it doesn't have an encryption equivalent. – Maarten Bodewes Jul 09 '20 at 07:47
  • Oww, I get it now... That is why we can decrypt while using RSA as shown in [here](https://www.youtube.com/watch?v=EA5jF_7FteM) . RSA is encryption (as well as signature generation) whereas ECDSA is signature algorithm. Thank you so much. I was on a totally different page before. @MaartenBodewes – Shilps Jul 09 '20 at 08:02

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Maarten Bodewes, in a comment on the question said:

"That is the encryption of the message by signing it and it's validation." I think that this is simply confusion. Signature generation is not signing with a private key. Transactions need to be put in the ledger, not encrypted. Usually this only comes up with RSA as ECDSA is just signature generation; it doesn't have an encryption equivalent.

Wai Ha Lee
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Shilps
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