1 / 11

Quantum Bit Commitment

Quantum Bit Commitment. Christian Schaffner DAIMI – Department of Computer Science BRICS – Basic Research in Computer Science NAT-årsfest June 3, 2005. Alice. Bob. Alice & Bob. *!¤. Alice. Bob. Divorce Problems. *!¤. who gets the house?. Alice. Bob.

emmanuel
Télécharger la présentation

Quantum Bit Commitment

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Quantum Bit Commitment Christian Schaffner DAIMI – Department of Computer Science BRICS – Basic Research in Computer Science NAT-årsfest June 3, 2005 A A R H U S U N I V E R S I T E T DAIMI – Department of Computer Science BRICS – Basic Research in Computer Science

  2. Alice Bob Alice & Bob *!¤ A A R H U S U N I V E R S I T E T DAIMI – Department of Computer Science BRICS – Basic Research in Computer Science

  3. Alice Bob Divorce Problems *!¤ who gets the house? A A R H U S U N I V E R S I T E T DAIMI – Department of Computer Science BRICS – Basic Research in Computer Science

  4. Alice Bob Coin-Flipping over the Telephone It’s tails, I get the house! A A R H U S U N I V E R S I T E T DAIMI – Department of Computer Science BRICS – Basic Research in Computer Science

  5. Alice Bob A Coin-Flipping Protocol not random! A A R H U S U N I V E R S I T E T DAIMI – Department of Computer Science BRICS – Basic Research in Computer Science

  6. Alice Bob The Solution A A R H U S U N I V E R S I T E T DAIMI – Department of Computer Science BRICS – Basic Research in Computer Science

  7. Alice Bob The Explanation A A R H U S U N I V E R S I T E T DAIMI – Department of Computer Science BRICS – Basic Research in Computer Science

  8. commit Alice Bob Bit-Commitment Scheme Bob‘s view open • important cryptographic primitive • hiding • binding A A R H U S U N I V E R S I T E T DAIMI – Department of Computer Science BRICS – Basic Research in Computer Science

  9. Alice Bob Particular Bit-Commitment Scheme commit to 0 Bob‘s view (n MegaBytes) commit to 1 bounded memory! (n MB) open • honest Alice needs: n • cheating Alice needs: 2¢n • Memorycheater< 2 ¢ Memoryhonest ) binding • perfectly hiding A A R H U S U N I V E R S I T E T DAIMI – Department of Computer Science BRICS – Basic Research in Computer Science

  10. Alice Bob Quantum Bit-Commitment Scheme Bob‘s view measure qbits in basis a n quantum bits bounded quantum memory! bounded memory! open classically: Memorycheater< 2 ¢ Memhonest • perfectly hiding • honest Alice needs no quantum memory • Memorycheater< n/2 ) binding A A R H U S U N I V E R S I T E T DAIMI – Department of Computer Science BRICS – Basic Research in Computer Science

  11. bounded quantum memory! bounded quantum memory! Alice Bob The End *!¤ A A R H U S U N I V E R S I T E T DAIMI – Department of Computer Science BRICS – Basic Research in Computer Science

More Related