{"id":36,"date":"2021-04-24T21:21:32","date_gmt":"2021-04-24T21:21:32","guid":{"rendered":"http:\/\/cryptonewcenter.com\/?p=36"},"modified":"2021-04-24T22:19:41","modified_gmt":"2021-04-24T22:19:41","slug":"ethereum-wont-hide-from-quantum-computers-behind-pos-shield","status":"publish","type":"post","link":"https:\/\/cryptonewcenter.com\/?p=36","title":{"rendered":"Ethereum Won&#8217;t Hide From Quantum Computers Behind PoS Shield"},"content":{"rendered":"\n<ul><li>There are two mechanisms by which a quantum computer might violate a cryptoasset.<\/li><li>Quantum computing poses a threat that concerns PoS and PoW in equal measure.<\/li><li>It\u2019s difficult to predict whether such a threat would emerge suddenly or gradually.<\/li><\/ul>\n\n\n\n<figure class=\"wp-block-image\"><img src=\"https:\/\/cimg.co\/w\/articles-attachments\/1\/608\/30a822bc46.jpg\" alt=\"Ethereum Won't Hide From Quantum Computers Behind PoS Shield 101\"\/><figcaption>Source: Adobe\/Bartek Wr\u00f3blewski<\/figcaption><\/figure>\n\n\n\n<p>Quantum computing has long been regarded as&nbsp;<a href=\"https:\/\/cryptonews.com\/coins\/bitcoin\/\">Bitcoin (BTC)<\/a>\u2019s \u2018bogeyman.\u2019 The popular fear is that, as secure as Bitcoin and other proof-of-work cryptoassets are in terms of standard cryptography, quantum computers could provide additional means of breaking them.<\/p>\n\n\n\n<p>One other popular assumption is that, because they don\u2019t use PoW, proof-of-stake cryptoassets such as&nbsp;<a href=\"https:\/\/cryptonews.com\/coins\/cardano\/\">Cardano (ADA)<\/a>,&nbsp;<a href=\"https:\/\/cryptonews.com\/coins\/dot-polkadot\/\">Polkadot (DOT)<\/a>, and&nbsp;<a href=\"https:\/\/cryptonews.com\/coins\/tron\/\">Tron (TRX)<\/a>&nbsp;(and&nbsp;<a href=\"https:\/\/cryptonews.com\/exclusives\/proof-of-disagreement-bitcoin-s-work-vs-ethereum-s-planned-s-9788.htm\">eventually<\/a>,&nbsp;<a href=\"https:\/\/cryptonews.com\/coins\/ethereum\/\">Ethereum (ETH)<\/a>) aren\u2019t as vulnerable to quantum computing attacks as networks like Bitcoin,&nbsp;<a href=\"https:\/\/cryptonews.com\/coins\/bitcoin-cash\/\">Bitcoin Cash (BCH)<\/a>&nbsp;and&nbsp;<a href=\"https:\/\/cryptonews.com\/coins\/litecoin\/\">Litecoin (LTC)<\/a>. However, according to a variety of computer scientists and crypto experts, it\u2019s not the consensus mechanism of a coin which creates the biggest risk in terms of quantum computers, but rather the signature system.<\/p>\n\n\n\n<p>In other words, given that the vast majority of PoS cryptoassets also use (non-quantum) cryptographic signature systems to sign individual transactions, they\u2019re nearly as vulnerable to quantum hacks as their PoW rivals. That said, the advent of sufficiently powerful quantum computers is still some way off, while their emergence is likely to incentivize a widespread shift to post-quantum cryptography.<\/p>\n\n\n\n<h2 id=\"51%-attacks-and-signature-attacks\">51% attacks and signature attacks<\/h2>\n\n\n\n<p>The important point to make when considering whether PoS is less vulnerable to quantum computing is that there are two mechanisms by which a quantum computer might violate a cryptoasset:<\/p>\n\n\n\n<ol type=\"1\"><li>The mechanism used to win the right to publish a block of transactions and to achieve distributed consensus (e.g. PoW or PoS)<\/li><li>The mechanism used to authorize individual transactions (typically involving some public\/private key signature system)<\/li><\/ol>\n\n\n\n<p>It\u2019s the first mechanism that affects PoW more than PoS, with Bitcoin and other proof-of-work coins theoretically vulnerable to a quantum computer-driven&nbsp;<a href=\"https:\/\/cryptonews.com\/tags\/51-attack\/\">51% attack<\/a>.<\/p>\n\n\n\n<p>That said, Marek Naro\u017cniak \u2014 a physics PhD student at&nbsp;<strong>New York University<\/strong>&nbsp;who has worked with Prof. Tim Byrne on research into quantum computing \u2014 explains that talk of a 51% attack perpetrated by quantum computers still remains theoretical.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote\"><p>\u201cIf someone has a sufficiently large quantum computer and wishes to perform a 51% attack \u2014 consisting of outperforming remaining miners and producing invalid blocks \u2014 it would have to be a really massive quantum machine. The reason for that is that Bitcoin&#8217;s proof-of-work is based on a hashing function for which there is no known efficient quantum algorithm [that can reverse it],\u201d he told&nbsp;<em>Cryptonews.com<\/em>.<\/p><\/blockquote>\n\n\n\n<p>But while Bitcoin\u2019s weakness compared to PoS cryptoassets is still pretty hypothetical, quantum computing poses another threat that concerns PoS and PoW in equal measure.<\/p>\n\n\n\n<p>\u201cEven if consensus requires no cryptographic \u2018work\u2019 [in the case of PoS] it still does rely on cryptography which is currently mainly based on elliptic curves which are vulnerable to quantum algorithms. An attacker with sufficiently powerful quantum computers could break other validators signatures and still mess with the consensus,\u201d said Naro\u017cniak.<\/p>\n\n\n\n<p>This is a concern echoed by other commentators. In an analysis&nbsp;<a href=\"https:\/\/www2.deloitte.com\/nl\/nl\/pages\/innovatie\/artikelen\/quantum-computers-and-the-bitcoin-blockchain.html\" target=\"_blank\" rel=\"noreferrer noopener\">published<\/a>&nbsp;by&nbsp;<strong>Deloitte<\/strong>, Bram Bosch wrote that around four million bitcoins are stored in addresses that use p2pk and p2pkh scripting, which is vulnerable to attacks via quantum computers.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote\"><p>\u201cPresently, about 25% of bitcoins in circulation are vulnerable to a quantum attack. Even in case one\u2019s own bitcoins are safe, one might still be impacted if other people will not (or cannot) take the same protection measures,\u201d he told&nbsp;<em>Cryptonews.com<\/em>.<\/p><\/blockquote>\n\n\n\n<p>Again, vulnerable scripting is something that could potentially affect PoS cryptoassets as well as Bitcoin, even if quantum computers are far from being widely available. And even without older schemes such as p2pk(h),&nbsp;<a href=\"https:\/\/en.wikipedia.org\/wiki\/Shor%27s_algorithm\" target=\"_blank\" rel=\"noreferrer noopener\">Shor<\/a>\u2019s algorithm \u2014 an algorithm for quantum computers \u2014 could be used to break many public-key cryptography systems.<\/p>\n\n\n\n<p>\u201cIf one has a sufficiently large and reliable quantum computer it would be possible to break the digital signature used to sign Bitcoin transactions. Such a person could use the modified Shor&#8217;s algorithm to sign transactions which take other people&#8217;s coins and transfer them at will,\u201d said Marek Naro\u017cniak.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote\"><p>He added that the worst thing about this \u201cis that it could not even be detected,\u201d and that PoS is just as vulnerable as PoW: \u201cIt would still be possible to produce transactions by breaking cryptographic signatures and producing transactions using someone else&#8217;s outputs.\u201d<\/p><\/blockquote>\n\n\n\n<h2 id=\"quantum-resistant-solutions\">Quantum-resistant solutions<\/h2>\n\n\n\n<p>Fortunately, current cryptographic research is more than aware of the theoretical threat posed by quantum computing, so you probably shouldn\u2019t start selling all of your crypto just yet.<\/p>\n\n\n\n<p>Researchers at&nbsp;<strong>Imperial College London<\/strong>&nbsp;published a&nbsp;<a href=\"https:\/\/www.doc.ic.ac.uk\/~wjk\/publications\/ilie-knottenbelt-stewart-marble-2019.pdf\" target=\"_blank\" rel=\"noreferrer noopener\">paper<\/a>&nbsp;in 2019 that outlined a protocol that would allow Bitcoin \u201cusers to securely move their funds from non-quantum-resistant outputs to those adhering to a quantum-resistant digital signature scheme.\u201d<\/p>\n\n\n\n<p>In September 2020, Australian computer scientists at&nbsp;<strong>Monash Blockchain Technology Centre<\/strong>&nbsp;and&nbsp;<strong>CSIRO\u2019<\/strong>s&nbsp;<strong>Data61<\/strong>&nbsp;developed what they&nbsp;<a href=\"https:\/\/www.csiro.au\/en\/news\/news-releases\/2020\/researchers-develop-worlds-most-efficient-quantum-safe-and-privacy-preserving-blockchain-protocol\" target=\"_blank\" rel=\"noreferrer noopener\">described<\/a>&nbsp;as \u201cthe world\u2019s most efficient blockchain protocol that is \u2026 secure against quantum computers.\u201d<\/p>\n\n\n\n<p>So solutions seem to be available, should a viable quantum computer emerge that could realistically be used to threaten PoW and PoS cryptoassets. And for most commentators, it\u2019s more likely that existing cryptos will shift to using post-quantum algorithms, rather than new post-quantum cryptoassets appear to take their places.<\/p>\n\n\n\n<p>\u201cI think the latter scenario of existing cryptocurrencies shifting to the use of post-quantum cryptography is going to be far more likely,\u201d said cryptocurrency journalist and analyst Roger Huang. \u201cIt occurs to me that it will be much harder to build the legitimacy, network effects, and exchange\/off-exchange volume of something like BTC from scratch than it is for BTC to just adopt post-quantum cryptography.\u201d<\/p>\n\n\n\n<p>For Bram Bosch, it still may be some time before the Bitcoin community (or any other) is compelled to actually implement solutions for quantum computing risks.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote\"><p>\u201cThe threat of a quantum attack would have to be very obvious and serious before the Bitcoin community would gain consensus on this matter. It\u2019s difficult to predict whether such a threat would emerge suddenly or gradually and as such, whether there would be time to react at all,\u201d he said.<\/p><\/blockquote>\n\n\n\n<p>That\u2019s precisely what\u2019s interesting about the danger posed by quantum computing: it\u2019s unknown, unpredictable quality. But given that it\u2019s a risk mostly to the signatures used by pretty much all cryptoassets, we do know it will be a threat to PoS and PoW cryptos alike<\/p>\n","protected":false},"excerpt":{"rendered":"<p>There are two mechanisms by which a quantum computer might violate a cryptoasset. Quantum computing poses a threat that concerns PoS and PoW in equal measure. It\u2019s difficult to predict whether such a threat would emerge suddenly or gradually. Quantum computing has long been regarded as&nbsp;Bitcoin (BTC)\u2019s \u2018bogeyman.\u2019 The popular [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":78,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"_links":{"self":[{"href":"https:\/\/cryptonewcenter.com\/index.php?rest_route=\/wp\/v2\/posts\/36"}],"collection":[{"href":"https:\/\/cryptonewcenter.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cryptonewcenter.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cryptonewcenter.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/cryptonewcenter.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=36"}],"version-history":[{"count":2,"href":"https:\/\/cryptonewcenter.com\/index.php?rest_route=\/wp\/v2\/posts\/36\/revisions"}],"predecessor-version":[{"id":79,"href":"https:\/\/cryptonewcenter.com\/index.php?rest_route=\/wp\/v2\/posts\/36\/revisions\/79"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cryptonewcenter.com\/index.php?rest_route=\/wp\/v2\/media\/78"}],"wp:attachment":[{"href":"https:\/\/cryptonewcenter.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=36"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cryptonewcenter.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=36"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cryptonewcenter.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=36"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}