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I understand that non repudiation intends to provide a mechanism that reliably proves that the sender of a message cannot deny sending the message. But does it also provide similar mechanisms to ensure the recipient of the message cannot deny receiving it.

  • It can work both ways. Sender A signs a message and send to receiver B. If a proof of receipt is need then we need another extra step - Receiver B signs the return message and send it to A, indicating that he has received it. – jingyang Aug 30 '14 at 6:28
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Non-repudiation binds the sender, not the recipient. I could, for example, digitally sign a message intended for you. I wouldn't be able to deny composing the message, but suppose I never sent it? You'd never get it, even though it was digitally signed.

I can't think of any mechanism not requiring the cooperation of the recipient that proves receipt of a message. (There's the email return receipt, but a recipient can disable that.)

  • I agree. You can bind the recipient (proof of receipt). It gives you non-repudiation of receipt. Often this is just a signed message that says "i received the following message: ...". It always has to involve the recipient, as he is the one to sign the answer. – fr00tyl00p Oct 25 '15 at 15:22
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Non-repudiation doesn’t just involve sending messages. It can also mean proving a user performed an action. Let's say a recipient receives bitcoins from a sender, but moves the bitcoins to a remote location. He then says that he did not receive them and asks the sender to send them again. Non-repudiation will be able to prove that he moved the bitcoins (via technologies like logging). Hence non-repudiation, in a way, prevents the recipient from denying he received the message.

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    Bitcoins aren't sent and received like an email, they are transferred atomically by transactions on a public, distributed, (nearly) tamperproof log called the block-chain. If your claimed payment to me is "confirmed" on that log you did pay (even if I deny it), if not you didn't. – dave_thompson_085 Aug 30 '14 at 9:42

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