Distributed, centrally authored block chain network

Patent metadata

Field	Value
Publication number	US-2017366357-A1
Application number	US-201715625946-A
Country	US
Kind code	A1
Filing date	Jun 16, 2017
Priority date	Jun 16, 2016
Publication date	Dec 21, 2017
Grant date	—

Abstract

A central service provider manages and writes transaction details to a private block chain network. Blocks of transaction records written onto the block chain by the central service provider are distributed to members of the block chain, thereby enabling data resiliency and self-verifiability. As the full block chain is available to members of the block chain network, the central service provider also ensures the privacy of transaction details by providing an assembled header and encrypted block of transaction records that are generated using a combination of symmetric and asymmetric cryptographic techniques. Altogether, the full block chain network is distributed across members of the block chain, but the members can only access and read transaction details in the block chain that they are authorized to view.

First claim

What is claimed is:

1 . A method comprising:
generating a symmetric key for a party; encrypting the symmetric key using a public key assigned to the party; generating a header comprising the encrypted symmetric key; receiving details of a transaction for a transfer of assets involving the party; encrypting the details of the transaction using the symmetric key generated for the party; generating a block of transaction records for a time period corresponding to the received transactions, the block of transaction records comprising the encrypted details of the transaction; and transmitting the header and the block of transaction records to the party.

2 . The method of claim 1 , further comprising:
generating a second symmetric key for a second party; and encrypting the second symmetric key using a public key assigned to the second party, wherein the generated header further comprises the encrypted second symmetric key.

3 . The method of claim 2 , further comprising:
receiving details of a second transaction for a transfer of assets involving the second party; and encrypting the details of the second transaction using the second symmetric key generated for the second party, wherein the block of transaction records further comprises the encrypted details of the second transaction.

4 . The method of claim 3 , further comprising transmitting the header and the block of transaction records to the second party.

5 . The method of claim 1 , wherein the header further comprises:
an encrypted symmetric key for an external system generated by encrypting the generated symmetric key using a public key of the external system; and an encrypted symmetric key for a central service provider generated by encrypting the generated symmetric key using a public key of the central service provider.

6 . The method of claim 5 , further comprising transmitting the header and the block of transaction records to the external system.

7 . The method of claim 1 , wherein each transaction record in the block comprises an envelope comprising a digital signature.

8 . The method of claim 1 , wherein each transaction record in the block further comprises a hash value identifying a previous transaction record in the block.

9 . The method of claim 1 , wherein the symmetric key generated for the party is valid for the time period of the block of transaction records.

9 . A non-transitory computer-readable medium comprising computer program code that, when executed by a processor of a computer system, causes the processor to:
generate a symmetric key for a party; encrypt the symmetric key using a public key assigned to the party; generate a header comprising the encrypted symmetric key; receive details of a transaction for a transfer of assets involving the party; encrypt the details of the transaction using the symmetric key generated for the party; generate a block of transaction records for a time period corresponding to the received transactions, the block of transaction records comprising the encrypted details of the transaction; and transmit the header and the block of transaction records.

10 . The non-transitory computer-readable medium method of claim 9 , further comprising computer program code that, when executed by the processor of the computer system, causes the processor to:
generate a second symmetric key for a second party; and encrypt the second symmetric key using a public key assigned to the second party, wherein the generated header further comprises the encrypted second symmetric key.

11 . The non-transitory computer-readable medium method of claim 10 , further comprising computer program code that, when executed by the processor of the computer system, causes the processor to:
receive details of a second transaction for a transfer of assets involving the second party; and encrypt the details of the second transaction using the second symmetric key generated for the second party, wherein the block of transaction records further comprises the encrypted details of the second transaction.

12 . The non-transitory computer-readable medium method of claim 11 , further comprising computer program code that, when executed by the processor of the computer system, causes the processor to transmit the header and the block of transaction records to the second party.

13 . The non-transitory computer-readable medium method of claim 9 , wherein the header further comprises:
an encrypted symmetric key for an external system generated by encrypting the generated symmetric key using a public key of the external system; and an encrypted symmetric key for a central service provider generated by encrypting the generated symmetric key using a public key of the central service provider.

14 . The non-transitory computer-readable medium method of claim 13 , further comprising computer program code that, when executed by the processor of the computer system, causes the processor to transmit the header and the block of transaction records to the external system.

15 . The non-transitory computer-readable medium method of claim 9 , wherein each transaction record in the block comprises an envelope comprising a digital signature.

16 . The non-transitory computer-readable medium method of claim 9 , wherein each transaction record in the block further comprises a hash value identifying a previous transaction record in the block.

17 . The non-transitory computer-readable medium method of claim 9 , wherein the symmetric key generated for the party is valid for the time period of the block of transaction records.

18 . A method for viewing private transactions, the method comprising:
receiving a header and a block of transaction records comprising encrypted transaction records; retrieving a private key in a key pair previously assigned to a member of a block chain network; identifying the encrypted symmetric key digitally signed by a public key in the key pair; decrypting the header using the private key to obtain a symmetric key; and decrypting transaction records of the block of transaction records using the symmetric key to obtain transaction details involving a transfer of assets.

19 . The method of claim 18 , wherein decrypting transaction records of the block of transaction records comprises:
identifying one or more encrypted transaction records signed by a digital key; and decrypting the identified one or more encrypted transaction records using the symmetric key.

20 . The method of claim 17 , wherein decrypting the header yields a plurality of symmetric keys, and wherein decrypting transaction records of the block of transaction records comprises decrypting a subset of the transaction records using each symmetric key of the plurality of symmetric keys, wherein each subset of transaction records decrypted by a symmetric key is different from another subset of transaction records decrypted by a different symmetric key.

Assignees

• Bank Of New York Mellon

Inventors

• Pattanaik Sarthak
• Pertsovskiy Vadim

Classifications

• H04L9/0825

  using asymmetric-key encryption or public key infrastructure [PKI], e.g. key signature or public key certificates · CPC title

• H04L9/3239

  involving non-keyed hash functions, e.g. modification detection codes [MDCs], MD5, SHA or RIPEMD · CPC title

• G06Q2220/00

  Business processing using cryptography · CPC title

• G06Q20/3829

  involving key management · CPC title

• H04L2209/56

  Financial cryptography, e.g. electronic payment or e-cash · CPC title