Wrapped-up blockchain

1. A method comprising:

for a blockchain comprising a series of blocks extending from an initial block to a terminal block, the initial block coding-consistent with an initial block integrity output stored within a subsequent block within the series:

after the initial block is secured by the initial block integrity output, determining content of the terminal block;

determining a terminal block integrity output coding-consistent with the content of the terminal block; and

wrapping-up the series by storing the terminal block integrity output within the initial block without introducing coding-inconsistence with the initial block integrity output.

2. The method of claim 1 , where the terminal block and the subsequent block comprise the same block.

3. The method of claim 1 , where storing the terminal block integrity output within the initial block without introducing coding-inconsistence with the initial block integrity output comprises:

performing a validity-preserving rewrite to the initial block.

4. The method of claim 3 , where performing the validity-preserving rewrite to the initial block comprises:

performing the validity-preserving rewrite using a key secret for the blockchain, performing the validity-preserving rewrite on behalf of a trusted party for the blockchain, or both.

5. The method of claim 1 , where:

the initial block and terminal block of the series comprise end blocks for the blockchain; and

wrapping-up the series comprises forming a closed-loop blockchain.

6. The method of claim 5 , further comprising storing a self-consistent record within the closed-loop blockchain.

7. The method of claim 1 , further comprising, for the terminal block, determining data to comply with a consensus mechanism for the blockchain after the initial block is secured by the initial block integrity output.

8. The method of claim 1 , where storing the terminal block integrity output within the initial block without introducing coding-inconsistence with the initial block integrity output comprises:

overwriting a null field within the initial block with the terminal block integrity output.

9. A system comprising:

a memory configured to:

store a blockchain comprising a series of blocks extending from an initial block to a terminal block, the initial block coding-consistent with an initial block integrity output stored within a subsequent block within the series; and

processing circuitry in data communication with the memory, the processing circuitry configured to:

determine a terminal block integrity output coding-consistent with the terminal block; and

after the initial block has been secured by the initial block integrity output, wrap-up the series by storing the terminal block integrity output within the initial block without introducing coding-inconsistence with the initial block integrity output by performing a validity-preserving rewrite to the initial block.

10. The system of claim 9 , where the terminal block and the subsequent block comprise the same block.

11. The system of claim 9 , where the processing circuitry is further configured to:

determine content of the terminal block after the initial block is secured by the initial block integrity output.

12. The system of claim 9 , where the processing circuitry is configured to:

perform the validity-preserving rewrite to the initial block by performing at least one from among:

the validity-preserving rewrite using a key secret for the blockchain, and

performing the validity-preserving rewrite on behalf of a trusted party for the blockchain.

13. The system of claim 9 , where:

the initial block and terminal block of the series comprise end blocks for the blockchain; and

the processing circuitry is configured to wrap-up the series by forming a closed-loop blockchain.

14. The system of claim 13 , where the processing circuitry is further configured to:

store a self-consistent record within the closed-loop blockchain.

15. The system of claim 9 , the processing circuitry is further configured to:

for the terminal block, determine data to comply with a consensus mechanism for the blockchain after the initial block is secured by the initial block integrity output.

16. The system of claim 9 , where the processing circuitry comprises rewrite circuitry configured to store the terminal block integrity output within the initial block without introducing coding-inconsistence with the initial block integrity output by overwriting a null field within the initial block with the terminal block integrity output.

17. A product comprising:

one or more machine-readable media other than a transitory signal; and

instructions stored on the one or more machine-readable media, the instructions configured to, when executed, cause a machine to:

for a blockchain comprising a series of blocks extending from an initial block to a terminal block, the initial block coding-consistent with an initial block integrity output stored within a subsequent block within the series:

determine content of the terminal block after the initial block is secured by the initial block integrity output;

determine a terminal block integrity output coding-consistent with the content of the terminal block; and

wrap-up the series by storing the terminal block integrity output within the initial block without introducing coding-inconsistence with the initial block integrity output.

18. The product of claim 17 , where the instructions are configured to cause the machine to store the terminal block integrity output within the initial block without introducing coding-inconsistence with the initial block integrity output by performing a validity-preserving rewrite to the initial block.

19. The product of claim 18 , where the instructions are configured to cause the machine to perform the validity-preserving rewrite to the initial block by:

performing the validity-preserving rewrite using a key secret for the blockchain, performing the validity-preserving rewrite on behalf of a trusted party for the blockchain, or both.

20. The product of claim 17 , where:

the initial block and terminal block of the series comprise end blocks for the blockchain; and

the instructions are configured to cause the machine to wrap-up the series by forming a closed-loop blockchain.

21. The product of claim 20 , where the instructions are further configured to cause the machine to store a self-consistent record within the closed-loop blockchain.

22. A method comprising:

accessing a blockchain within memory, the blockchain comprising:

an initial block;

a terminal block including an initial block integrity output configured to secure the initial block through coding-consistence with the initial block or via a chain of one or more interim blocks between the initial block and terminal block on the blockchain; and

wrapping-up the blockchain by storing, while maintaining coding-consistence with initial block integrity output, a terminal block integrity output within the initial block, the terminal block integrity output determined at the same time or subsequent to the initial block integrity output, the terminal block integrity output configured to secure the terminal block.

23. The method of claim 22 , where wrapping-up the blockchain comprises performing a validity-preserving rewrite on the initial block.

24. The method of claim 23 , where performing the validity-preserving rewrite on the initial block comprises: performing the validity-preserving rewrite using a key secret for the blockchain, performing the validity-preserving rewrite on behalf of a trusted party for the blockchain, or both.

25. The method of claim 22 , where wrapping-up the blockchain comprises generating a closed-loop blockchain.