Blockchain Secrets Sharing: Security and Efficiency Strategies Revealed
"Exploring the feasibility of blockchain in keeping secrets secure and recoverable, this study discusses proactive secret-sharing protocols for maintaining security against adversaries while ensuring scalability and communication efficiency. Dive into the complexities and solutions outlined in the research paper by Fabrice Benhamouda, Craig Gentry, Sergey Gorbunov, and other experts in the field."
Download Presentation
Please find below an Image/Link to download the presentation.
The content on the website is provided AS IS for your information and personal use only. It may not be sold, licensed, or shared on other websites without obtaining consent from the author. If you encounter any issues during the download, it is possible that the publisher has removed the file from their server.
You are allowed to download the files provided on this website for personal or commercial use, subject to the condition that they are used lawfully. All files are the property of their respective owners.
The content on the website is provided AS IS for your information and personal use only. It may not be sold, licensed, or shared on other websites without obtaining consent from the author.
E N D
Presentation Transcript
CAN A BLOCKCHAIN KEEP A SECRET? Fabrice Benhamouda, Craig Gentry, Sergey Gorbunov, Shai Halevi, Hugo Krawczyk, Chengyu Lin, Tal Rabin, Leonid Reyzin https://eprint.iacr.org/2020/464
Can a Blockchain be a Trusted Party? Public PoS ?1 This Photo by Unknown Author is licensed under CC BY-NC-ND ?(?1,?2,?3) ?2 ?3 Meh Great for integrity/immutability Not so much for secrecy
This Work: A Basic Secrecy Setting A client deposits a secret at the blockchain To be revealed only when the time is right More generally used only in the prescribed manner Example: publish a puzzle, deposit a solution Reveal the solution if not found by next week Can form a basis for many applications
Security and Efficiency The secret must remain a secret Unknown to the adversary, but still recoverable As long as we have honest majority of stake Even when the adversary is mobile Efficiency: want a scalable solution Communication/work does not increase as time go by, or as more nodes are joining the network Plausible practicality: No obfuscation/witness-encryption We seek solutions based on proactive secret-sharing
Why is it Hard? For scalability, communication only by a small committee But then a mobile adversary can corrupt them all Previous work assumed assumed that committees have honest majority We provide a mechanism to ensure it Solution: keep committee members anonymous So adversary cannot target them Player replaceability Player replaceability: player sends a single message, revealing its identity only after completing its job only after completing its job How to (re)share a secret among an unknown committee?
How is it Done? No time to tell you, read the paper https://ia.cr/2020/464 ?1 ?2 ?3 ?4 Nominating committees reshare reshare reshare reshare Secret-sharing committees ?1 ?2 ?3 ?4
The End Result A scalable proactive secret-sharing protocol With player replaceability Assuming that the adversary controls < of the stake Can be implemented under DDH, DCR, LWE, Raises an interesting new open problem about anonymous encryption under selective opening attacks Can conceivably be made practical Involves only proving short statements with short witnesses , independent of total stake or the blockchain history
The End Result A scalable proactive secret-sharing protocol With player replaceability Assuming that the adversary controls < of the stake Can be implemented under DDH, DCR, LWE, Raises an interesting new open problem about anonymous encryption under selective opening attacks Can conceivably be made practical Involves only proving short statements with short witnesses , independent of total stake or the blockchain history Thank You
