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Quiz Entry - updated: 2026.07.14

What are the two types of non-repudiation, and why does the distinction matter?

Non-repudiation of origin prevents a sender from denying they sent a message; non-repudiation of receipt prevents a receiver from denying they received it.

The BSI distinguishes:

Type German Protection against...
Non-repudiation of origin Nichtabstreitbarkeit der Herkunft Sender denying they sent a specific message
Non-repudiation of receipt Nichtabstreitbarkeit des Erhalts Receiver denying they received a specific message

Why this matters in practice:

  • Origin: When Alice signs a contract digitally, she cannot later claim she didn't sign it (the digital signature proves she did)
  • Receipt: When Bob's system acknowledges receiving the signed contract, he cannot later claim he never received it

How it's achieved:

  • Origin → Digital signatures (the sender signs with their private key)
  • Receipt → Signed acknowledgments or delivery receipts (the receiver signs a confirmation)

In this framework, non-repudiation (Verbindlichkeit) is integrated into data authenticity — it's not treated as a separate security goal but as a component of the broader authenticity concept. This is one area where different textbooks organize things differently.

From Quiz: KRYPTOG / Introduction to Cryptology | Updated: Jul 14, 2026