Controlled cryptographic private key release

Patent metadata

Field	Value
Publication number	US-12470374-B2
Application number	US-202318533103-A
Country	US
Kind code	B2
Filing date	Dec 7, 2023
Priority date	Jun 26, 2017
Publication date	Nov 11, 2025
Grant date	Nov 11, 2025

Abstract

Techniques are presented to instantiate an event chain with a first block, wherein the first block is timestamped with an instantiation time; monitor for an event associated with a monitoring request; signal to other nodes in a plurality of nodes based on the monitoring by providing a commitment to a plurality of nodes in the plurality of nodes, wherein based on occurrence of the event providing either a dummy signal or an indicator comprising an encryption private key share held by the node, wherein the commitment is provided to the other nodes in the plurality of nodes; monitor for commitments from the other nodes in the plurality of nodes, wherein each commitment comprises a dummy signal or an encryption key share; process the commitments received from the other nodes to obtain an encryption private key share; and identify the encryption private key based on the analysis of the commitments.

First claim

What is claimed is:

1 . A computer-implemented method of identifying an encryption private key, the method implemented by a node in a plurality of nodes, the method comprising:
instantiating an event chain with a first block, wherein the first block is timestamped with an instantiation time; monitoring for an event associated with a monitoring request; signalling to other nodes in a plurality of nodes based on the monitoring by providing a commitment to a plurality of nodes in the plurality of nodes, wherein based on occurrence of the event providing either a dummy signal or an indicator comprising an encryption private key share held by the node, wherein the commitment is provided to the other nodes in the plurality of nodes; monitoring for commitments from the other nodes in the plurality of nodes, wherein each commitment comprises a dummy signal or an encryption key share; processing the commitments received from the other nodes to obtain an encryption private key share; and identifying the encryption private key based on the analysis of the commitments.

2 . The computer-implemented method of claim 1 , wherein an event chain comprises a temporary blockchain.

3 . The computer-implemented method of claim 2 , wherein the event chain is a proof-of-stake blockchain mined by the plurality of nodes that each have stakes encumbered with a group-stake public key.

4 . The computer-implemented method of claim 1 , wherein the blocks of the event chain are generated at an interval specified in the monitoring request.

5 . The computer-implemented method of claim 4 , wherein the interval is selected to be less than a latency the requester indicates for the key release following the event.

6 . The computer-implemented method of claim 1 , wherein the monitoring for the event comprises monitoring of a network server.

7 . The computer-implemented method of claim 1 , wherein the dummy signal is of the same length as the encryption private key share.

8 . The computer-implemented method of claim 1 , wherein the dummy signal is randomly generated by the node.

9 . The computer-implemented method of claim 1 , wherein the commitment further comprises a group-stake public key share for the respective node.

10 . The computer-implemented method of claim 1 , wherein the commitment is signed based on a group-stake private key share held by the node performing the method.

11 . The computer-implemented method of claim 1 , wherein the commitment is provided in a block on the event chain.

12 . The computer-implemented method of claim 11 , wherein each block is time stamped.

13 . The computer-implemented method of claim 1 , wherein the encryption private key is reconstructed based on the encryption private key shares obtained from the other nodes.

14 . The computer-implemented method of claim 13 , wherein the encryption private key is reconstructed in accordance with a threshold key construction scheme.

15 . A non-transitory computer-readable storage medium comprising computer-executable instructions that, when executed, configure a processor to execute operations:
instantiating an event chain with a first block, wherein the first block is timestamped with an instantiation time; monitoring for an event associated with a monitoring request; signalling to other nodes in a plurality of nodes based on the monitoring by providing a commitment to a plurality of nodes in the plurality of nodes, wherein based on occurrence of the event providing either a dummy signal or an indicator comprising an encryption private key share held by the node, wherein the commitment is provided to the other nodes in the plurality of nodes; monitoring for commitments from the other nodes in the plurality of nodes, wherein each commitment comprises a dummy signal or an encryption key share; processing the commitments received from the other nodes to obtain an encryption private key share; and identifying the encryption private key based on the analysis of the commitments.

Assignees

• Nchain Licensing Ag

Inventors

• Fletcher John
• Trevethan Thomas

Classifications

• H04L9/3247

  involving digital signatures · CPC title

• H04L9/3213

  using tickets or tokens, e.g. Kerberos (network architectures or network communication protocols for entities authentication using tickets in a packet data network H04L63/0807) · CPC title

• H04L9/30

  Public key, i.e. encryption algorithm being computationally infeasible to invert or user's encryption keys not requiring secrecy · CPC title

• G06F21/64

  Protecting data integrity, e.g. using checksums, certificates or signatures · CPC title

• H04L9/50

  using hash chains, e.g. blockchains or hash trees · CPC title