Quantum resistant blockchain and cryptocurrency, the full analysis in seven parts. Part 4C.


You can read part 1 here, and part 2 here, and part 3A here, and part 3B here, and part 3C here, and part 4A here, and part 4B here

The performance of blockchains that upgrade, could be different after the upgrade.

The current post-quantum signature schemes (Including the submissions to the NIST competition), will drastically increase the block size and take more resources to compute. This may slow down the amount of transactions per second, which a lot of projects aim to speed up instead of slow down. Quantum resistant signature schemes will mean bigger signatures. That has consequences for the performance of a blockchain, unless big innovative changes are made. So at the moment where quantum resistance becomes a must, something unexpected will happen. Projects that have postponed an implementation of quantum resistant signature schemes will be set back. The upgrade to a safe signature scheme will actually be partly a downgrade for pretty much all existing projects. But refering back to the existing quantum resistant blockchain “The Quantum Resistant Ledger: QRL” (uses XMSS) which is fully up and running at this time of writing, the only reason for QRL to change signature schemes is if a better, more efficient post-quantum signature scheme will be developed compared to the post-quantum signature scheme they use right now. Who knows, there might be something better available in the future. If this is indeed better, going from XMSS to something better, will be an over all upgrade. (For example, the competition run by NIST will either come up with something better, more efficient, or there will be nothing new to recommend at all. And as mentioned before, XMSS could be approved and recommended this year.). So while all other projects will partly downgrade performance wise, an already quantum resistant blockchain will either stay the same or upgrade and perform better than before.

How do bigger signatures influence the speed with which transactions are sent and confirmed on a blockchain? First a quick summary of the way transactions are handled: All miners, collect all transactions that people are sending in a transaction pool. There, transactions wait until a miner puts a number of these collected transaction in a block. This is where a block is constructed. After he has constructed a block, he has to solve a hash puzzle applied on his list of transactions that he registered on his block. The miner who has solved his hash puzzle, is allowed to put his block on the network. If this block will eventually be part of the longest chain, the transaction will be confirmed and validated. Either the size of the block will be influenced by bigger signatures, or if the block size is fixed, the amount of transactions that fit in a block will be influenced.

In the next part I elaborate how the use of quantum resistant signature schemes affect blockchain performance. You can continue reading part 4D here

 

How do you rate this article?


0

0

Allen Walters
Allen Walters

Fascinated by blockchain and future proofing cryptocurrency. Discover the tech before it gets relevant. Twitter: @IgnoranceIt


Quantum resistant blockchain in 7 parts
Quantum resistant blockchain in 7 parts

Quantum resistant blockchain and cryptocurrency, the full analysis in seven parts.

Send a $0.01 microtip in crypto to the author, and earn yourself as you read!

20% to author / 80% to me.
We pay the tips from our rewards pool.