Quantum computing has been on the tech radar for some time now, but it has also been lurking in the background of the blockchain ecosystem for very different reasons. The new advancement of computing allows for complex equations and problems to be solved exponentially quicker than is currently available.
However, it has always been predominantly a futuristic, almost science fiction-like pursuit; for blockchain that has been just fine as well because we have been warned that quantum computation could render existing encryption standards obsolete, threatening the security of every significant blockchain.
This week, news has emerged that Google has made a recent quantum computing breakthrough, achieving quantum supremacy. It is being reported that Google, using a quantum computer, managed to perform a calculation in just over three minutes that would take the world’s most powerful supercomputer 10,000 years.
This could mean panic stations for blockchain as all that has been achieved thus far could be wiped out, and without the right provisions, all the promise and potential could be eliminated overnight.
However, the term quantum supremacy refers to the moment when a quantum computer outperforms the world’s best classical computer in a specific test. This is just the first step, but it is a rather large step that means the spotlight is once again on blockchain to try and resist this kind of technology which can unravel its cryptographic algorithms in minutes.
Google’s first steps
Google has described the recent achievement as a “milestone towards full-scale quantum computing.” They have also said this milestone puts a marker in the ground on which they can start rapidly progressing towards full quantum computing – another concerning statement form blockchains.
Details are a little scarce on what Google has achieved, and how they have done it, but previous proposals essentially involve the quantum computer racing a classical computer simulating a random quantum circuit.
According to Gizmodo, it has been long known that Google has been testing a 72-qubit device called Bristlecone with which it hoped to achieve quantum supremacy and the initial report from the Financial Times says that the supremacy experiment was instead performed with a 53-qubit processor codenamed Sycamore.
However, it would be a little early to start abandoning all hope with Bitcoin, blockchain, and the emerging technology as it is a bit more complicated than that. More so, there is already technology and projects in place that has been trying to prepare for an age of quantum computing where blockchain is resistant.
Are blockchains ready to resist?
So, if quantum computing is making significant breakthroughs, is there any evidence of blockchain’s being prepared for this new age, and a new threat? There has been news of blockchain builders putting out quantum-resistant chains, such as E-cash inventor David Chaum and his latest cryptocurrency, Praxxis.
QAN is another project that says it is ready for the quantum computing age, has reacted quickly to the news of Google’s breakthrough with Johann Polecsak, CTO of QAN, telling Bitcoin.com: “The notion of Google achieving a quantum breakthrough sounds very dramatic, but in reality, it’s hard to gauge the significance at this time. How can we be sure that Google’s quantum computer is more powerful than D-wave’s, for example, which surpassed 1,000 qubits four years ago?”
I also reached out to Polecsak to find out more about the threat of quantum computing when, and if, it reaches its pinnacle.
“We should definitely be worried,” he told me, “Many IT professionals and CTOs, including the earlier m, are neglecting and denying quantum computing threats with the simple reasoning that once it’s seriously coming, we’ll have to redesign almost everything from scratch, and that must surely be a long time ahead.”
“The truth is that one can already rent quantum computers for experimenting with possible attack algorithms and testing theoretical approaches. The maths behind breaking currently used public key cryptography – EC and RSA – were proven, we just need more qubits.”
“In cryptography, it’s best to prepare for the worst, and one can observe in recent literature that past skeptics now instantiate their crypto protocols in a post-quantum setting – just it case. Users shouldn’t worry now, but experts should prepare before it’s too late.”
What it means to be quantum-resistant
Of course, the technological aspect of the race between quantum computing and blockchain quantum resistance is immense, and it is also quite nuanced. It is not as if quantum computing will, like a light switch, be available and all blockchains will suddenly be vulnerable – but it is still important to be prepared. As it stands, there probably is not enough preparation and planning in place, according to Polecsak.
“Blockchains won’t be ready for such a breakthrough. Since transaction history is the backbone of blockchains, such an improvement in quantum computing could be catastrophic for the whole transaction history,” added the CTO. “There is an extra layer of protection with Bitcoin’s double hashing but assuming a quantum computer is capable of Shor on secp256k1 it’s safe to assume it’s also capable of Grover256. Also, we don’t know bounds for SHA regarding quantum circuits.”
“As for QAN blockchain platform, it is not a linear comparison or a race where we need to keep up side-by-side with increasing qubits. Being Quantum-safe does not mean that we are just increasing bits in currently used algorithms, but that we take a totally different approach which resists the known Quantum attacks by design.”
Prepare to resist
As science-fictiony as it sounds, quantum computing is a threat that needs to be taken seriously in the world of blockchains. It may not be the kill switch that everyone imagines because of media hype, but it certainly something that should be on the radar for anyone involved in the ecosystem.
It is not only because of what has been accomplished in blockchain thus far but also because of what is being built and promised in the space. Blockchain is a major technology revolution on the horizon, and as it permeates deeper into enterprises and governments it would be catastrophic for all that has been done to be undone, and all that has been promised to be eliminated.