Big-O scaling - By Gavin Andresen - The Bitcoin Forum
Andresen on BitCoin and Virtual Currency - Econlib
Bitcoin Foundation - WikiMili, The Free Encyclopedia
Gavin Andresen on BitCoin and Virtual Currency Hacker News
I recently recounted the history of the block size controversy for someone and thought I'd repost it here
Bitcoin development was initially led by an anonymous figure named Satoshi Nakamoto who created the project "Bitcoin: a Peer-to-peer Electronic Cash System" The project mostly languished in obscurity until in late 2010 it was revealed that Bitcoin was being used to evade the ban on Wikileaks contributions. (A good summary of Bitcoin's early history can be found here.) Satoshi was opposed to Bitcoin being used for something as controversial as funding Wikileaks, and in one of his last messages, wrote "It would have been nice to get this attention in any other context. WikiLeaks has kicked the hornet's nest, and the swarm is headed towards us." (link). Satoshi vanished shortly thereafter. When Satoshi disappeared, he left the project effectively in the control of Gavin Andresen, one of the early contributors to the project. Gavin has been characterized as something of a naive academic. It wasn't long before Gavin had been approached by the CIA and agreed to visit and do a presentation. So we know that Bitcoin was on the CIA's radar by 2011. Bitcoin-as-introduced had an Achilles heel. To prevent a specific kind of denial-of-service attack, Satoshi had added a "block size limit" to prevent flooding attacks. Satoshi's plan was to raise the limit as usage increased. Satoshi and the early Bitcoiners such as myself did not envision that the limit might itself be a vulnerability. A near-complete history of the block size limit controversy is here. I'll attempt to summarize my experience with some references. Now it's almost 2020, and by now we've all become much more attuned to the scope of what three-letter-agencies have been doing to manipulate social media platforms. But in 2012 that was tinfoil-hat stuff across most of the internet. In 2012, the Bitcoin subreddit was one of the key places people went for discussion about what was happening in Bitcoin. That, and the bitcointalk forum. The history of what happened has been well documented with sources in places like here and here. The TLDR is
"Theymos" gains control of bitcoin and bitcointalk
Theymos receives a 6000 BTC donation (worth in the low millions of dollars at the time) to develop new forum software. No software is developed.
a company is created, "Blockstream" whose mission depends on keeping Bitcoin's block size limit in place. Blockstream ostensibly plans to sell alternatives to using the Bitcoin blockchain when the blockchain becomes unusable due to congestion. Strangely, those alternatives all look suspiciously like "banking."
(2014) Trolling on social media pivots from "anti-Bitcoin" to "anti-raising-the-block-size-limit". Obstruction to raising the limit suddenly a serious conflict within Bitcoin Core development.
(2015) MIT Media Labs' Digital Currency Initiative hires Gavin Andresen and Wladimir van der Laan. Gavin and Wladimir are the two Core developers who have final authority over the Bitcoin Core software.
(2015) Gavin Andresen and Mike Hearn become the leaders of a counter-Blockstream movement called Bitcoin XT. XT was a new Bitcoin client that would cause the block size to be raised if enough people used it.
(2015) Theymos famously begins banning everyone from Bitcoin who supports Bitcoin XT, or who speaks out in favor of raising the block size, or questions the moderation policy, etc. This temporary measure continues to this day.
(2015) Banned OG Bitcoiners try to raise awareness by creating an uncensored subreddit btc to expose the apparent takeover of the Bitcoin project by Blockstream
(2017) a compromise (bait-and-switch) is suddenly proposed from nowhere and suddenly gains widespread support: Segwit2X. This will raise the block size limit by 2X, but only after Segwit is activated. Segwit activates, but support for the 2X block size limit increase quickly evaporates.
Throughout all of this, Blockstream steadfastly argued that it didn't control the Bitcoin Core software. Blockstream pointed to Chaincode Labs who funded several key bitcoin developers and the MIT Media Labs "Digital Currency Initiative" who funded Gavin, Cory, and Wladimir. Gavin and Wladimir in particular had the authority to merge changes into the Bitcoin Core software and as such effectively could decide what did and did not go into the software. As an ostensibly academic organization, Gavin and Wladimir etc could act with intellectual honesty and without coercion. Except Gavin left the Digital Currency Initiative in 2017, saying that while he wasn't pressured to quit, he "didn't want to feel obligated to any person or organization." Fast forward to 2019, and we learn the fascinating news that the MIT Media Labs were funded in part by none other than Jeffrey Epstein, who it turns out just so happened to be a staunch advocate of the Blockstream approach. So really, Bitcoin development was corralled: Blockstream was paying a bunch of devs, and Blockstream-Friendly MIT Media Labs were paying the others. If you're still reading this, you probably wonder what it is about the Blockstream strategy that is so "bad." Aren't they just proposing a different way to solve Bitcoin's problems? The original idea for Bitcoin was a "peer to peer cash system" - - the idea being that if Alice wants to buy something from Bob, she can just give him some tokens - - just like cash. The new vision of bitcoin promoted by Blockstream and Core is "store of value". Under this model, you buy Bitcoins like you might speculate on gold - you buy some and you hold it. Later, if you want to purchase something, you sell your Bitcoins for some other payment method (or use an IOU against a deposit, just like a bank), and use that for purchases. It should be apparent after a moment of thought that the original concept (Alice hands Bob some cash which Bob can then spend how he likes) is vastly more disruptive than the model in which Alice buys Bitcoin on a government-regulated exchange, holds them hoping they'll appreciate in value, and then sells them for Euros or dollars. In model one, the currency is essentially outside the domain of gatekeepers, and could completely disintermediate the entire existing financial system just like Napster for money. In model two, Bitcoin is no more disruptive than shares of a gold fund.
Hello again. It's been a while. People have been emailing me about once a week or so for the last year to ask if I'm coming back to Bitcoin now that Bitcoin Cash exists. And a couple of weeks ago I was summoned on a thread called "Ask Mike Hearn Anything", but that was nothing to do with me and I was on holiday in Japan at the time. So I figured I should just answer all the different questions and answers in one place rather than keep doing it individually over email. Firstly, thanks for the kind words on this sub. I don't take part anymore but I still visit occasionally to see what people are talking about, and the people posting nice messages is a pleasant change from three years ago. Secondly, who am I? Some new Bitcoiners might not know. I am Satoshi. Just kidding. I'm not Satoshi. I was a Bitcoin developer for about five years, from 2010-2015. I was also one of the first Bitcoin users, sending my first coins in April 2009 (to SN), about 4 months after the genesis block. I worked on various things:
My main effort was an implementation of a Java library called bitcoinj. This was the engine used in the first p2p mobile wallet ("Bitcoin Wallet for Android"), and the first p2p desktop wallet that was faster to run than Bitcoin [Core] itself (MultiBit). These together were responsible for around 2.5 million user installs at a time when downloading the full block chain was becoming too slow for normal users to tolerate and the only alternative was a "bitbank" or cloud-hosted wallet. It was used in the first trustless gambling site (SatoshiDice), over 100 products and projects, and many academic research papers.
With Gavin Andresen and others I designed some upgrades to the Bitcoin protocol like Bloom filtering and BIP70.
With Matt Corrallo I implemented and demonstrated the first version of (micro)payment channels. I put together a demo of a file server that charged micropayments using a GUI called Payfile (mentioned in New Scientist here). I used to have a video of this but unfortunately it no longer seems to be on YouTube. Payment channels went on to be used in the design of the Lightning Network.
You can see a trend here - I was always interested in developing peer to peer decentralised applications that used Bitcoin. But what I'm best known for is my role in the block size debate/civil war, documented by Nathaniel Popper in the New York Times. I spent most of 2015 writing extensively about why various proposals from the small-block/Blockstream faction weren't going to work (e.g. on replace by fee, lightning network, what would occur if no hard fork happened, soft forks, scaling conferences etc). After Blockstream successfully took over Bitcoin Core and expelled anyone who opposed them, Gavin and I forked Bitcoin Core to create Bitcoin XT, the first alternative node implementation to gain any serious usage. The creation of XT led to the imposition of censorship across all Bitcoin discussion forums and news outlets, resulted in the creation of this sub, and Core supporters paid a botnet operator to force XT nodes offline with DDoS attacks. They also convinced the miners and wider community to do nothing for years, resulting in the eventual overload of the main network. I left the project at the start of 2016, documenting my reasons and what I expected to happen in my final essay on Bitcoin in which I said I considered it a failed experiment. Along with the article in the New York Times this pierced the censorship, made the wider world aware of what was going on, and thus my last gift to the community was a 20% drop in price (it soon recovered).
The last two years
Left Bitcoin ... but not decentralisation. After all that went down I started a new project called Corda. You can think of Corda as Bitcoin++, but modified for industrial use cases where a decentralised p2p database is more immediately useful than a new coin. Corda incorporates many ideas I had back when I was working on Bitcoin but couldn't implement due to lack of time, resources, because of ideological wars or because they were too technically radical for the community. So even though it's doesn't provide a new cryptocurrency out of the box, it might be interesting for the Bitcoin Cash community to study anyway. By resigning myself to Bitcoin's fate and joining R3 I could go back to the drawing board and design with a lot more freedom, creating something inspired by Bitcoin's protocol but incorporating all the experience we gained writing Bitcoin apps over the years. The most common question I'm asked is whether I'd come back and work on Bitcoin again. The obvious followup question is - come back and work on what? If you want to see some of the ideas I'd have been exploring if things had worked out differently, go read the Corda tech white paper. Here's a few of the things it might be worth asking about:
Corda's data model is a UTXO ledger, like Bitcoin. Outputs in Corda (called "states") can be arbitrary data structures instead of just coin amounts, so you don't need hacks like coloured coins anymore. You can track arbitrary fungible assets, but you can also model things like the state of a loan, deal, purchase order, crate of cargo etc.
Transactions are structured as Merkle trees.
Corda has a compound key format that can represent more flexible conditions than CHECKMULTISIG can.
Smart contracts are stateless predicates like in Bitcoin, but you can loop like in Ethereum. Unlike Bitcoin and Ethereum we do not invent our own VM or languages.
Transactions can have files attached to them. Smart contracts in Corda are stored in attachments and referenced by hash, so large programs aren't duplicated inside every transaction.
The P2P network is encrypted.
Back in 2014 I wrote that Bitcoin needed a store and forward network, to make app dev easier, and to improve privacy. Corda doesn't have a store and forward network - Corda is a store and forward network.
It has a "flow framework" that makes structured back-and-forth conversations very easy to program. This makes protocols like payment channelss a lot quicker and easier to implement, and would have made Lighthouse much more straightforward. A big part of my goal with Corda was to simplify the act of building complicated decentralised applications, based on those Bitcoin experiences. Lighthouse took about 8 months of full time work to build, but it's pretty spartan anyway. That's because Bitcoin offers almost nothing to developers who want to build P2P apps that go beyond simple payments. Corda does.
The flow framework lets you do hard things quickly. For example, we took part in a competition called Project Ubin, the goal of which was to develop something vaguely analogous in complexity to the Lightning Network or original Ripple (decentralised net-out of debts). But we had about six weeks and one developer. We successfully did that in the time allowed. Compare that to dev time for the Lightning Network.
Corda scales a lot better than Bitcoin, even though Bitcoin could have scaled to the levels needed for large payment networks with enough work and time. It has something similar to what Ethereum calls "sharding". This is possible partly because Corda doesn't use proof of work.
It has a mechanism for signalling the equivalent of hard forks.
It provides much better privacy. Whilst it supports techniques like address randomisation, it also doesn't use global broadcast and we are working on encrypting the entire ledger using Intel SGX, such that no human has access to the raw unencrypted data and such that it's transparent to application developers (i.e. no need to design custom zero knowledge proofs)
There are many reasons why BTC will remain the gold standard and not BCH. BTC Advantages over BCH:
A deep pool of very talented set of developers who have deep knowledge in the critical technologies that underpin Bitcoin: cryptography, peer-to-peer communication, game theory, protocol development, and very importantly, security
An unparalleled track record for releasing well-tested and secure code (the recent Parity-eth scandal shows just how bad even one small bug can be)
Has an ethos that tries to minimize centralization pressures of all kinds, mining, client, and providers. This includes trying to ensure upgrades are backwards compatible. For people who use alternate implementations of Bitcoin other than Bitcoin Core, or who customize the client, this is critical. One small example: Greg Maxwell noted that users and alternate clients "may have their own lengthy patching and qualification process". When those aren't taken into account, "forced upgrades erode decentralization and privileges hosted wallets/apis/pools over running your own infrastructure"
BTC has a censorship resistance ethos that is critical to ensuring that no one party controls the coin (one of the key attributes that makes Bitcoin special). Even the CEO of Xapo, who was a Segwit2X signer recently acknowledged he got a bit too eager with his support of a fork and that censorship resistance is critical.
Has a large ecosystem working on scaling solutions. Some on-chain (like segwit, MAST), and others on the way that may also improve privacy such as Schnorr. Many competing groups are also working on second layer solutions like lightning or drivechains/sidechains. Just this week there was a new whitepaper on more ways to do funding of micropayment channels that might make lightning even better. There is an incredible amount of spectacular science and research going on here
Has a deep, thriving ecosystem of developers, wallets, companies, and users committed to it's success and development
A wide deployment of different clients, libraries, and supporting systems
Makes it a bit harder to skip proof of work in a covert way with ASICBoost
Significant performance improvements and rapid ongoing development and research
BTC transaction volume, people actually using the coin is literally 25X times higher than BCH! The little volume in BCH is most likely speculative since virtually no one accepts it.
Heavy influence from one mining group that pushed for it and most likely funded it. This is the same mining group that held back segwit (a scaling upgrade, security improvement, and bugfix for malleability). This was done against the wishes of nearly every Bitcoin engineer (even former engineer Gavin Andresen supported Segwit)
Only 1 full-time developer, Amaury Sechet (deadalnix). When someone asked him at a recent conference to list other people who work on it, his only response was "freetrader". That doesn't exactly inspire confidence since the entire foundation of Bitcoin is the code.
Almost no track record yet for releases or security
Potential scaling problems: If blocks started to actually fill up many users would not be able to run a full node because the costs of bandwidth and also storage would become problematic since bandwidth requirements increase at a much faster rate than the block size. This would make those users subject to people or large organizations who want to manipulate the coin since only large players and miners may be able to run full nodes as the costs rise.
No track record on how disputes between developers are resolved or when something is production ready, no diverse set of developer testing
A fledgling set of clients and apps, almost nothing compared to BTC
A distribution schedule that means faster inflation and more coins, and also, a far lower period of time before new coin creation comes to a halt entirely. This combined with the idea of trying to keep transaction fees to a minimum means the future security and viability of the coin is much less certain than BTC
A likely exploitation by miners of covert ASICBoost, skipping some proof of work but only for privileged miners covered by a patent
Lack of acceptance in the marketplace. Some exchanges support it, but it lacks the critical mass of retailers and people that accept it (the network effects of existing BTC works against this coin)
Low transaction volume (roughly 80 transactions per second compared to Bitcoin's 2150 per second.
High likelihood of a price crash once some exchanges like Coinbase/GDAX free up coins and users can sell them
I have been watching Bitcoin for a long time, and the main thing I've learned is don't overreact to flashes in the pan, weak hands, and anytime a "panic" is happening. What really pays in the long-run is sticking with things that have a proven track record, a high quality set of software engineers and computer scientists, and a critical mass of ecosystem. Nothing compares to Bitcoin in these regards!! Bitcoin has a very bright future ahead!
Why The US Government Have Likely Already Approved Bitcoin
Hey Reddit, throwaway account. I'm currently doing some research for an article I hope to have published later this month. I have a very, very rough draft at the moment and your feedback would be lovely. The Elephant in the Room Bitcoin is an enigma. It has renowned economists like Paul Krugman entirely perplexed whilst Silicon Valley CEO's are falling over one another to get a piece of the action. The headlines change on a daily basis: “It's A Ponzi Scheme!”, “It's Gold 2.0!” , “It's A Bubble!”, “It's The New Internet!”. As a result of these, often conflicting articles, it's value shoots up and down like a yo-yo, swinging wildly to the slightest bit of news, good or bad. Of course, these swings wouldn't be so exaggerated if there was a simple way to address the elephant in the room...is bitcoin legal? Government officials have been oddly quiet in addressing this question. Aside from some rudimentary FINCEN guidelines and a vague ECB report, there's been no statement one way or another about its legal status. Whilst I can't provide any definitive proof as to what decisions have and are being made behind closed government doors, I do think it's just possible we already have enough circumstantial evidence to suggest that the US government has already given Bitcoin the thumbs up. Satoshi's Lament Back in December 2010 Satoshi was involved in a heated discussion amongst Bitcoin developers on BitcoinTalk as to whether they should support Julian Assange by offering Bitcoin as a means to bypass the notorious banking blockade that had rendered Wikileaks' cash reserves impotent. Bitcoin's creator, Satoshi Nakamoto, was extremely wary that any association with Julian and Wikileaks would 'bring too much heat' to the project. “No, don't 'bring it on'” he pleaded with his fellow developers. “The project needs to grow gradually so the software can be strengthened along the way.” He went on to clarify. “I make this appeal to WikiLeaks not to try to use Bitcoin. Bitcoin is a small beta community in its infancy. You would not stand to get more than pocket change, and the heat you would bring would likely destroy us at this stage.” By 'destroy us', he was likely talking about a government or corporation pulling the trigger on this nascent project. Amongst other things, Satoshi was fearful that if a nefarious entity such as a commercial bank got wind of the project, at that point in time they could have easily compromised the project by purchasing enough computing power to overrun the network (known as a 51% attack). Despite Satoshi's protestations, Wikileaks went along and adopted Bitcoin and, it seemed Satoshi's worst fears were confirmed when, just 4 months later in April 2011, Gavin Andresen (now lead developer at the Bitcoin Foundation) announced that the C.I.A. had contacted him. “I'm going to give a presentation about Bitcoin at the C.I.A headquarters in June at an emerging technologies conference...I accepted the invitation to speak because the fact that I was invited means Bitcoin is already on their radar, and I think it might be a good chance to talk about why I think Bitcoin will make the world a better place. I think the goals of this project are to create a better currency...I don't think any of those goals are incompatible with the goals of government.” Satoshi disappeared shortly after. Gavin recently spoke to the New Yorker about the event. "...I think people realized once I got invited to speak at the C.I.A. that there was no kind of hiding. They, whoever “they” are, already knew about this project." [Source: http://www.newyorker.com/online/blogs/elements/2013/04/the-future-of-Bitcoin.html] The Silk Road Goes Live 2011 also saw the release of the notorious 'Ebay for Drugs' website, Silk Road. It received much press attention, first breaking in June via Gawker where a developer described his experience of buying LSD through the site as "Kind of like being in the future". It was clear that the Silk Road was where Bitcoin would find its first major real-world trading niche and it's not a coincidence that the BTC price, client downloads and trading volume began to skyrocket after its inception. [Source: http://gizmodo.com/5805928/the-underground-website-where-you-can-buy-any-drug-imaginable] A week after the Gawker article, Senator Chuck Schumer called a press conference where he went on record demanding that the Silk Road be shut down “Something must be done about Silk Road...Literally, it allows buyers and users to sell illegal drugs online, including heroin, cocaine, and meth, and users sell by hiding their identities through a program that makes them virtually untraceable...[it's] the most brazen attempt to peddle drugs online that we have ever seen. It's more brazen than anything else by lightyears." he told the assembled press. As an aside, it is worth noting that the program that “hides user identities” is TOR, developed by the US Naval Research laboratory and endorsed by Senator Hilary Clinton (Schuman's former co-Senator from the state of New York) as “an important tool for freedom of expression around the world”. Indeed, the TOR Project claims that over 80% of its funding in 2012 came directly from the U.S Government [Source: Tor Project Annual Report 2012] The Radar Screen Lights Up Suddenly, thanks to the Silk Road and Wikileaks, Bitcoin was now on the radar of those in public office. The question on everyones lips must have been “How do we kill Bitcoin (and by extension Wikileaks and Silkroad)?” The C.I.A, thanks to Gavin, were now fully aware of the threat Bitcoin posed to the the current monetary system, and the illegal activities it was funding via Silk Road and other places would have done nothing but confound their concerns (or so you would think). They must have also known (just as Satoshi did) that if there was ever an opportunity to kill Bitcoin (either with regulation, criminal proceedings and/or a 51% attack) then it was back then, in 2011, with the network still in its infancy, that they should strike. We should have expected the kind of domain seizures that we saw with the likes of Megaupload; Bitcointalk, Bitcoin.org and the Bitcoin Foundation should have been wiped off the map. They could have also moved with the banks to shutdown any accounts seen to be associated with Bitcoin trading (as we saw happen with Online Gambling websites during the Bush Regime). They could have then disrupted what remained of the Bitcoin network by performing a relatively cheap and simple 51% attack. And yet, none of that happened... Bitcoin.org and the Bitcoin Foundation have been left to prosper and go from strength to strength. VC's, Wall Street traders and the average Joe were all left free to pump money into this burgeoning experiment without any government intervention whatsoever. Eric, Julian and the Bilderberg Group Back in 2010 Google dipped their toes into the world of virtual currencies, acquiring a little known company called Jambool for $70m. For awhile they ran a platform called Social Gold which was later usurped in 2011 by Facebook Credits (Facebook's attempt at a virtual currency). This was phased out in mid-2012. Techcrunch cites that this was likely due to the problems Facebook had encountered in educating the public about using another form of currency, and goes on to speculate that by offering a centralised means of exchange, Facebook may have also faced increasing legal and regulatory scrutiny. In June 2011, Julian Assange met Eric Schmidt online in a secret 5 hour chat in which they discussed - amongst other things - Bitcoin. The full transcript - which was leaked last month - is available here: http://wikileaks.org/Transcript-Meeting-Assange-Schmidt Also in attendance at the meeting was Jared Cohen, a former Secretary of State advisor to Hillary Clinton, Scott Malcomson, Director of Speechwriting for Ambassador Susan Rice at the US State Department and current Communications Director of the International Crisis Group, and Lisa Shields, Vice President of the Council on Foreign Relations. Here's an excerpt: JA: ...there’s also a very nice little paper that I’ve seen in relation to Bitcoin, that… you know about Bitcoin? ES: No. JA: Okay, Bitcoin is something that evolved out of the cypherpunks a couple of years ago, and it is an alternative… it is a stateless currency. … JA: And very important, actually. It has a few problems. But its innovations exceed its problems. Now there has been innovations along these lines in many different paths of digital currencies, anonymous, untraceable etc. People have been experimenting with over the past 20 years. The Bitcoin actually has the balance and incentives right, and that is why it is starting to take off. The different combination of these things. No central nodes. It is all point to point. One does not need to trust any central mint…. ... ES: That's very interesting So, now we know Bitcoin was on the radar of the C.I.A, various politicians and, thanks to Julian, the CEO of Google was now beginning to get an inkling as to its disruptive potential. Just 13 days prior to the Assange meet, Eric had attended the annual meeting of the notoriously secretive Bilderberg Group in St. Moritz, Switzerland and went on to attend the meet again in June 2012. Topics of discussion included:
Emerging Economies: Roles and Responsibilities
Economic and National Security in a Digital Age
Technological Innovation in Western Economies: Stagnation or Promise?
Imbalances, Austerity and Growth
Some of the 2011/12 attendees included:
Josef Ackermann (Chairman of Deutsche Bank),
Jean-Claude Trichet (President of the European Central Bank),
Chris Hughes (Co-Founder of Facebook),
Reid Hoffman (CEO of Linkedin),
Jeff Bezos (CEO of Amazon)
Keith Alexander (Commander, US Cyber Command; Director, NSA).
Heads of Barclays Bank, AXXA, HSBC and the President of The World Bank Group were also in attendance. [Source: http://www.bilderbergmeetings.org/index.php] To see so many tech luminaries in attendance at Bilderberg is indicative of the kind of power and respect that geeks and hackers now command in shaping the world stage. Just how many high-level decisions are being influenced by this new technorati is hard to say, but in a rapidly changing world where technology is moving faster than the old rules remain relevant, we are seeing that people, united through technology on a global scale – not governments – are dictating the speed of change. Joining The Dots None of this means that bitcoins ride is going to be friction-free - just because Eric Schmidt is open to the idea of bitcoin displacing traditional currencies (as he and Jared Cohen alluded to in a recent CNBC interview), does not mean that Douglas Flint (Group Chairman, HSBC) is going to be equally enthused. However, I do think that if we join up all the dots the general conclusion that we can draw looks overwhelmingly positive for the future of bitcoin. That so many powerful actors within the intelligence community, technology industry and government have let bitcoin survive this long is almost an endorsement itself. It suggests to me that any nefarious corporations that attempt to shutdown bitcoin because of a perceived threat to their business model, will be met by those same powerful actors coming together to ensure they will have a very tough fight on their hands. Indeed, in the years to come, we may well see Hilary Clinton coming out to trumpet bitcoin as “an important tool for freedom of expression around the world” in much the same way she praised the TOR project. And perhaps, ultimately, we will discover that bitcoin, like TOR, was also developed by the US Naval Research Laboratory. Though I prefer to think it was just some lone genius sitting in his attic who accidentally changed the world. Whatever may be the case, it seems that - for now at least - our governments have handed their people a rare gift – the freedom to shape their own future. It's up to us to try not to screw that up.
Abstract So far, the topic of merged mining has mainly been considered in a security context, covering issues such as mining power centralization or crosschain attack scenarios. In this work we show that key information for determining blockchain metrics such as the fork rate can be recovered through data extracted from merge mined cryptocurrencies. Specifically, we reconstruct a long-ranging view of forks and stale blocks in Bitcoin from its merge mined child chains, and compare our results to previous findings that were derived from live measurements. Thereby, we show that live monitoring alone is not sufficient to capture a large majority of these events, as we are able to identify a non-negligible portion of stale blocks that were previously unaccounted for. Their authenticity is ensured by cryptographic evidence regarding both, their position in the respective blockchain, as well as the Proof-of-Work difficulty. Furthermore, by applying this new technique to Litecoin and its child cryptocur rencies, we are able to provide the first extensive view and lower bound on the stale block and fork rate in the Litecoin network. Finally, we outline that a recovery of other important metrics and blockchain characteristics through merged mining may also be possible. References
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A. P. Ozisik, G. Bissias, and B. Levine, “Estimation of miner hash rates and consensus on blockchains,” arXiv preprint arXiv:1707.00082, 2017, accessed:2017-09-25. [Online]. Available: https://arxiv.org/pdf/1707.00082.pdf
J. A. D. Donet, C. Perez-Sola, and J. Herrera-Joancomart ´ ´ı, “The bitcoin p2p network,” in Financial Cryptography and Data Security. Springer, 2014, pp. 87–102. [Online]. Available: http://fc14.ifca.ai/bitcoin/papers/bitcoin14 submission 3.pdf
R. Matzutt, J. Hiller, M. Henze, J. H. Ziegeldorf, D. Mullmann, O. Hohlfeld, and K. Wehrle, ¨ “A quantitative analysis of the impact of arbitrary blockchain content on bitcoin,” in Proceedings of the 22nd International Conference on Financial Cryptography and Data Security (FC). Springer, 2018. [Online]. Available: http://fc18.ifca.ai/preproceedings/6.pdf
M. Grundmann, T. Neudecker, and H. Hartenstein, “Exploiting transaction accumulation and double spends for topology inference in bitcoin,” in 5th Workshop on Bitcoin and Blockchain Research, Financial Cryptography and Data Security 18 (FC). Springer, 2018. [Online]. Available: http://fc18.ifca.ai/bitcoin/papers/bitcoin18-final10.pdf
A. Judmayer, N. Stifter, P. Schindler, and E. Weippl, “Pitchforks in cryptocurrencies: Enforcing rule changes through offensive forking- and consensus techniques (short paper),” in CBT’18: Proceedings of the International Workshop on Cryptocurrencies and Blockchain Technology, Sep 2018. [Online]. Available: https://www.sba-research.org/wpcontent/uploads/2018/09/judmayer2018pitchfork 2018-09-05.pdf
Abstract Transaction throughput, confirmation latency and confirmation reliability are fundamental performance measures of any blockchain system in addition to its security. In a decentralized setting, these measures are limited by two underlying physical network attributes: communication capacity and speed-of-light propagation delay. Existing systems operate far away from these physical limits. In this work we introduce Prism, a new proof-of-work blockchain protocol, which can achieve 1) security against up to 50% adversarial hashing power; 2) optimal throughput up to the capacity C of the network; 3) confirmation latency for honest transactions proportional to the propagation delay D, with confirmation error probability exponentially small in CD ; 4) eventual total ordering of all transactions. Our approach to the design of this protocol is based on deconstructing the blockchain into its basic functionalities and systematically scaling up these functionalities to approach their physical limits. References
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Ittay Eyal and Emin G¨un Sirer. Majority is not enough: Bitcoin mining is vulnerable. Communications of the ACM, 61(7):95–102, 2018.
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Aggelos Kiayias, Alexander Russell, Bernardo David, and Roman Oliynykov. Ouroboros: A provably secure proof-of-stake blockchain protocol. In Annual International Cryptology Conference, pages 357–388. Springer, 2017.
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Yoad Lewenberg, Yoram Bachrach, Yonatan Sompolinsky, Aviv Zohar, and Jeffrey S Rosenschein. Bitcoin mining pools: A cooperative game theoretic analysis. In Proceedings of the 2015 International Conference on Autonomous Agents and Multiagent Systems, pages 919–927. International Foundation for Autonomous Agents and Multiagent Systems, 2015.
Yoad Lewenberg, Yonatan Sompolinsky, and Aviv Zohar. Inclusive block chain protocols. In International Conference on Financial Cryptography and Data Security, pages 528–547. Springer, 2015.
Chenxing Li, Peilun Li, Wei Xu, Fan Long, and Andrew Chi-chih Yao. Scaling nakamoto consensus to thousands of transactions per second. arXiv preprint arXiv:1805.03870, 2018.
Wenting Li, S´ebastien Andreina, Jens-Matthias Bohli, and Ghassan Karame. Securing proof-of-stake blockchain protocols. In Data Privacy Management, Cryptocurrencies and Blockchain Technology, pages 297–315. Springer, 2017.
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Christopher Natoli and Vincent Gramoli. The balance attack against proof-of-work blockchains: The r3 testbed as an example. arXiv preprint arXiv:1612.09426, 2016.
Kartik Nayak, Srijan Kumar, Andrew Miller, and Elaine Shi. Stubborn mining: Generalizing selfish mining and combining with an eclipse attack. In Security and Privacy (EuroS&P), 2016 IEEE European Symposium on, pages 305–320. IEEE, 2016.
Rafael Pass, Lior Seeman, and Abhi Shelat. Analysis of the blockchain protocol in asynchronous networks. In Annual International Conference on the Theory and Applications of Cryptographic Techniques, pages 643–673. Springer, 2017.
Rafael Pass and Elaine Shi. Fruitchains: A fair blockchain. In Proceedings of the ACM Symposium on Principles of Distributed Computing. ACM, 2017.
Rafael Pass and Elaine Shi. Hybrid consensus: Efficient consensus in the permissionless model. In LIPIcs-Leibniz International Proceedings in Informatics, volume 91. Schloss Dagstuhl-Leibniz-Zentrum fuer Informatik, 2017.
Rafael Pass and Elaine Shi. Thunderella: Blockchains with optimistic instant confirmation. In Annual International Conference on the Theory and Applications of Cryptographic Techniques, pages 3–33. Springer, 2018.
Peter R Rizun. Subchains: A technique to scale bitcoin and improve the user experience. Ledger, 1:38–52, 2016.
Ayelet Sapirshtein, Yonatan Sompolinsky, and Aviv Zohar. Optimal selfish mining strategies in bitcoin. In International Conference on Financial Cryptography and Data Security, pages 515–532. Springer, 2016.
Y Sompolinsky and A Zohar. Phantom: A scalable blockdag protocol, 2018.
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Yonatan Sompolinsky and Aviv Zohar. Secure high-rate transaction processing in bitcoin. In International Conference on Financial Cryptography and Data Security, pages 507–527. Springer, 2015.
Abstract We present and validate a novel mathematical model of the blockchain mining process and use it to conduct an economic evaluation of the double-spend attack, which is fundamental to all blockchain systems. Our analysis focuses on the value of transactions that can be secured under a conventional double-spend attack, both with and without a concurrent eclipse attack. Our model quantifies the importance of several factors that determine the attack's success, including confirmation depth, attacker mining power, and any confirmation deadline set by the merchant. In general, the security of a transaction against a double-spend attack increases roughly logarithmically with the depth of the block, made easier by the increasing sum of coin turned-over (between individuals) in the blocks, but more difficult by the increasing proof of work required. In recent blockchain data, we observed a median block turnover value of 6 BTC. Based on this value, a merchant requiring a single confirmation is protected against only attackers that can increase the current mining power by 1% or less. However, similar analysis shows that a merchant that requires a much longer 72 confirmations (~12 hours) will eliminate all potential profit for any double-spend attacker adding mining power less than 40% of the current mining power. References
Bonneau, J., Miller, A., Clark, J., Narayanan, A., Kroll, J., Felten, E.: Sok: Research perspectives and challenges for bitcoin and cryptocurrencies. In: IEEE S&P. pp. 104–121 (May 2015), http://doi.org/10.1109/SP.2015.14
Meiklejohn, S., Pomarole, M., Jordan, G., Levchenko, K., McCoy, D., Voelker, G., Savage, S.: A Fistful of Bitcoins: Characterizing Payments Among Men with No Names. In: Proc. ACM IMC. pp. 127–140 (2013), http://doi.acm.org/10.1145/2504730.2504747
Sasson, E.B., Chiesa, A., Garman, C., Green, M., Miers, I., Tromer, E., Virza, M.: Zerocash: Decentralized anonymous payments from bitcoin. In: IEEE S&P. pp. 459–474 (2014), http://dx.doi.org/10.1109/SP.2014.36
Abstract We make several contributions that quantify the real-time hash rate and therefore the consensus of a blockchain. We show that by using only the hash value of blocks, we can estimate and measure the hash rate of all miners or individual miners, with quanti able accuracy. We apply our techniques to the Ethereum and Bitcoin blockchains; our solution applies to any proof-of-work-based blockchain that relies on a numeric target for the validation of blocks. We also show that if miners regularly broadcast status reports of their partial proof-of- work, the hash rate estimates are signi cantly more accurate at a cost of slightly higher bandwidth. Whether using only the blockchain, or the additional information in status reports, merchants can use our techniques to quantify in real-time the threat of double-spend attacks. References  2015. The Bitcoin Lightning Network: Scalable Off-Chain Instant Payments. https://lightning.network/lightning-network-paper.pdf. (July 2015).  2016. Gnosis. https://www.gnosis.pm. (November 2016).  Asaph Azaria, Ariel Ekblaw, Thiago Vieira, and Andrew Lippman. 2016. "MedRec: Using Blockchain for Medical Data Access and Permission Management. In Proc. Intl. Conf. on Open and Big Data. 25–30.  Adam Back, Matt Corallo, Luke Dashjr, Mark Friedenbach, Gregory Maxwell, Andrew Miller, Andrew Poelstra, Jorge Timón, and Pieter Wuille. 2014. Enabling Blockchain Innovations with Pegged Sidechains. Technical report. (Oct 22 2014).  Simon Barber, Xavier Boyen, Elaine Shi, and Ersin Uzun. 2012. Bitter to better—how to make bitcoin a better currency. In International Conference on Financial Cryptography and Data Security. Springer, 399–414.  Bryan Bishop. 2015. bitcoin-dev mailling list: Weak block thoughts... https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2015-Septembe011158.html. (Sep 2015).  bitcoin 2015. Confirmation. https://en.bitcoin.it/wiki/Confirmation. (February 2015).  Joseph Bonneau. 2015. How long does it take for a Bitcoin transaction to be confirmed? https://coincenter.org/2015/11/what-does-it-meanfor-a-bitcoin-transaction-to-be-confirmed/. (November 2015).  J. Bonneau, A. Miller, J. Clark, A. Narayanan, J.A. Kroll, and E.W. Felten. 2015. SoK: Research Perspectives and Challenges for Bitcoin and Cryptocurrencies. In IEEE S&P. 104–121. http://doi.org/10.1109/ SP.2015.14  George Casella and Roger L. Berger. 2002. Statistical inference. Brooks Cole, Pacific Grove, CA. http://opac.inria.frecord=b1134456  Kyle Croman et al. 2016. On Scaling Decentralized Blockchains . In Workshop on Bitcoin and Blockchain Research.  Digix. 2017. https://www.dgx.io/. (Last retrieved June 2017).  DigixDAO. 2017. https://www.dgx.io/dgd/. (Last retrieved June 2017).  J. Douceur. 2002. The Sybil Attack. In Proc. Intl Wkshp on Peer-to-Peer Systems (IPTPS).  Bradley Efron. 1982. The jackknife, the bootstrap and other resampling plans. Society for industrial and applied mathematics (SIAM).  Ethash. 2017. https://github.com/ethereum/wiki/wiki/Ethash. (Last retrieved June 2017).  ethereum. Ethereum Homestead Documentation. http://ethdocs.org/en/latest/. (????).  Etheria. 2017. http://etheria.world. (Last retrieved June 2017).  Ittay Eyal and Emin Gün Sirer. 2014. Majority is not enough: Bitcoin mining is vulnerable. Financial Cryptography (2014), 436–454. http://doi.org/10.1007/978-3-662-45472-5_28  William Feller. 1968. An Introduction to Probability Theory and its Applications: Volume I. Vol. 3. John Wiley & Sons London-New YorkSydney-Toronto.  Juan Garay, Aggelos Kiayias, and Nikos Leonardos. 2015. The bitcoin backbone protocol: Analysis and applications. In Annual International Conference on the Theory and Applications of Cryptographic Techniques. Springer, 281–310.  Arthur Gervais, Ghassan O. Karame, Karl Wust, Vasileios Glykantzis, Hubert Ritzdorf, and Srdjan Capkun. 2016. On the Security and Performance of Proof of Work Blockchains. https://eprint.iacr.org/2016/555. (2016).  Hashcash. 2017. https://en.bitcoin.it/wiki/Hashcash. (Last retrieved June 2017).  Ethan Heilman, Leen Alshenibr, Foteini Baldimtsi, Alessandra Scafuro, and Sharon Goldberg. 2017. TumbleBit: An untrusted Bitcoincompatible anonymous payment hub. In Proc. ISOC Network and Distributed System Security Symposium (NDSS).  Svante Janson. 2014. Tail Bounds for Sums of Geometric and Exponential Variable. Technical Report. Uppsala University.  Litecoin. 2017. https://litecoin.org. (Last retrieved June 2017).  Satoshi Nakamoto. 2009. Bitcoin: A Peer-to-Peer Electronic Cash System. https://bitcoin.org/bitcoin.pdf. (May 2009).  A. Pinar Ozisik, Gavin Andresen, George Bissias, Amir Houmansadr, and Brian Neil Levine. 2016. A Secure, Efficient, and Transparent Network Architecture for Bitcoin. Technical Report UM-CS-2016-006. University of Massachusetts, Amherst, MA. https://web.cs.umass.edu/publication/details.php?id=2417  Meni Rosenfeld. 2012. Analysis of hashrate-based double-spending. https://bitcoil.co.il/Doublespend.pdf. (December 2012).  Ayelet Sapirshtein, Yonatan Sompolinsky, and Aviv Zohar. 2015. Optimal Selfish Mining Strategies in Bitcoin. https://arxiv.org/pdf/1507.06183.pdf. (July 2015).  Eli Ben Sasson, Alessandro Chiesa, Christina Garman, Matthew Green, Ian Miers, Eran Tromer, and Madars Virza. 2014. Zerocash: Decentralized Anonymous Payments from Bitcoin. In IEEE S&P. 459–474. http://dx.doi.org/10.1109/SP.2014.36  Yonatan Sompolinsky and Aviv Zohar. 2015. Secure high-rate transaction processing in Bitcoin. Financial Cryptography and Data Security (2015). http://doi.org/10.1007/978-3-662-47854-7_32  Yonatan Sompolinsky and Aviv Zohar. 2016. Bitcoin’s Security Model Revisited. https://arxiv.org/abs/1605.09193. (May 2016).  F. Tschorsch and B. Scheuermann. 2016. Bitcoin and Beyond: A Technical Survey on Decentralized Digital Currencies. IEEE Communications Surveys Tutorials PP, 99 (2016), 1–1. https://doi.org/10.1109/COMST. 2016.2535718  Marko Vukolić. 2015. The quest for scalable blockchain fabric: Proof-ofwork vs. BFT replication. In International Workshop on Open Problems in Network Security. Springer, 112–125.
Shutting down or restricting the uses of bank accounts, thereby forbidding clients to buy crypto, is a blatant affront to the rights of civil liberty, manifested, but not limited to, in the rights to private property and free speech (562 points, 262 comments)
I believe Bitcoin Core/Blockstream is now attempting to infiltrate Bitcoin Cash in the same manner that they did with Bitcoin Segwit. They are suddenly befriending Bitcoin Cash. Only in that way can they destroy from within. Do not be fooled. (401 points, 166 comments)
You have $100 worth of BTC. So you purchase an item for $66, but have to pay a $17 fee. Now you have $17 worth of Bitcoin left, but it costs $17 more to move it. So $66 item effectively cost you $100. #Thanks BlockStream (1420 points, 433 comments)
2025 points: kairepaire's comment in As of today, Steam will no longer support Bitcoin as a payment method
2018 points: vbuterin's comment in "So no worries, Ethereum's long term value is still ~0." -Greg Maxwell, CTO of Blockstream and opponent of allowing Bitcoin to scale as Satoshi had planned.
1215 points: vbuterin's comment in Vitalik Buterin tried to develop Ethereum on top of Bitcoin, but was stalled because the developers made it hard to build on top of Bitcoin. Vitalik only then built Ethereum as a separate currency
1211 points: LiamGaughan's comment in As of today, Steam will no longer support Bitcoin as a payment method
Since this is a pressing and prevalent issue, I thought maybe condensing the essential arguments into one mega thread is better than rehashing everything in new threads all the time. I chose a FAQ format for this so a certain statement can be answered. I don't want to re-post everything here so where appropriate I'm just going to use links. Disclaimer: This is biased towards big blocks (BIP 101 in particular) but still tries to mention the risks, worries and fears. I think this is fair because all other major bitcoin discussion places severely censor and discourage big block discussion.
What is the block size limit?
The block size limit was introduced by Satoshi back in 2010-07-15 as an anti-DoS measure (though this was not stated in the commit message, more info here). Ever since, it has never been touched because historically there was no need and raising the block size limit requires a hard fork. The block size directly limits the number of transactions in a block. Therefore, the capacity of Bitcoin is directly limited by the block size limit.
Why does a raise require a hard fork?
Because larger blocks are seen as invalid by old nodes, a block size increase would fork these nodes off the network. Therefore it is a hard fork. However, it is possible to downsize the block limit with a soft fork since smaller blocks would still be seen as valid from old nodes. It is considerably easier to roll out a soft fork. Therefore, it makes sense to roll out a more ambitious hard fork limit and downsize as needed with soft forks if problems arise.
What is the deal with soft and hard forks anyways?
It is the Chicken and Egg problem applied to future growth of Bitcoin. If companies do not see how Bitcoin can scale long term, they don't invest which in turn slows down adoption and development. See here and here.
Does an increase in block size limit mean that blocks immediately get larger to the point of the new block size limit?
No, blocks are as large as there is demand for transactions on the network. But one can assume that if the limit is lifted, more users and businesses will want to use the blockchain. This means that blocks will get bigger, but they will not automatically jump to the size of the block size limit. Increased usage of the blockchain also means increased adoption, investment and also price appreciation.
Which are the block size increase proposals?
See here. It should be noted that BIP 101 is the only proposal which has been implemented and is ready to go.
What is the long term vision of BIP 101?
BIP 101 tries to be as close to hardware limitations regarding bandwidth as possible so that nodes can continue running at normal home-user grade internet connections to keep the decentralized aspect of Bitcoin alive. It is believed that it is hard to increase the block size limit, so a long term increase is beneficial to planning and investment in the Bitcoin network. Go to this article for further reading and understand what is meant by "designing for success". BIP 101 vs actual transaction growth visualized: http://imgur.com/QoTEOO2 Note that the actual growth in BIP 101 is piece-wise linear and does not grow in steps as suggested in the picture.
What is up with the moderation and censorship on bitcoin.org, bitcointalk.org and /bitcoin?
Proponents of a more conservative approach fear that a block size increase proposal that does not have "developeexpert consensus" should not be implemented via a majority hard fork. Therefore, discussion about the full node clients which implement BIP 101 is not allowed. Since the same individuals have major influence of all the three bitcoin websites (most notably theymos), discussion of Bitcoin XT is censored and/or discouraged on these websites.
Who governs or controls Bitcoin Core anyways? Who governs Bitcoin XT? What is Bitcoin governance?
Bitcoin Core is governed by a consensus mechanism. How it actually works is not clear. It seems that any major developer can "veto" a change. However, there is one head maintainer who pushes releases and otherwise organizes the development effort. It should be noted that the majority of the main contributors to Bitcoin Core are Blockstream employees. BitcoinXT follows a benevolent dictator model (as Bitcoin used to follow when Satoshi and later Gavin Andresen were the lead maintainers). It is a widespread believe that Bitcoin can be separated into protocol and full node development. This means that there can be multiple implementations of Bitcoin that all follow the same protocol and overall consensus mechanism. More reading here. By having multiple implementations of Bitcoin, single Bitcoin implementations can be run following a benevolent dictator model while protocol development would follow an overall consensus model (which is enforced by Bitcoin's fundamental design through full nodes and miners' hash power). It is still unclear how protocol changes should actually be governed in such a model. Bitcoin governance is a research topic and evolving.
What are the arguments against a significant block size increase and against BIP 101 in particular?
The main arguments against a significant increase are related to decentralization and therefore robustness against commercial interests and government regulation and intervention. More here (warning: biased Wiki article). Another main argument is that Bitcoin needs a fee market established by a low block size limit to support miners long term. There is significant evidence and game theory to doubt this claim, as can be seen here. Finally, block propagation and verification times increase with an increased block size. This in turn increases the orphan rate of miners which means reduced profit. Some believe that this is a disadvantage to small miners because they are not as well connected to other big miners. Also, there is currently a large miner centralization in China. Since most of these miners are behind the Great Firewall of China, their bandwidth to the rest of the world is limited. There is a fear that larger block propagation times favor Chinese miners as long as they have a mining majority. However, there are solutions in development that can drastically reduce block propagation times so this problem will be less of an issue long term.
What is up with the fee market and what is the Lightning Network (LN)?
Major Bitcoin Core developers believe that a fee market established by a low block size is needed for future security of the bitcoin network. While many believe fundamentally this is true, there is major dispute if a fee market needs to be forced by a low block size. One of the main LN developers thinks such a fee market through low block size is needed (read here). The Lightning Network is a non-bandwidth scaling solution. It uses payment channels that can be opened and closed using Bitcoin transactions that are settled on the blockchain. By routing transactions through many of these payment channels, in theory it is possible to support a lot more transactions while a user only needs very few payment channels and therefore rarely has to use (settle on) the actual blockchain. More info here.
How does LN and other non-bandwidth scaling solutions relate to Bitcoin Core and its long term scaling vision?
Bitcoin Core is headed towards a future where block sizes are kept low so that a fee market is established long term that secures miner incentives. The main scaling solution propagated by Core is LN and other solutions that only sometimes settle transactions on the main Bitcoin blockchain. Essentially, Bitcoin becomes a settlement layer for solutions that are built on top of Bitcoin's core technology. Many believe that long term this might be inevitable. But forcing this off-chain development already today seems counterproductive to Bitcoin's much needed growth and adoption phase before such solutions can thrive. It should also be noted that no major non-bandwidth scaling solution (such as LN) has been tested or even implemented. It is not even clear if such off-chain solutions are needed long term scaling solutions as it might be possible to scale Bitcoin itself to handle all needed transaction volumes. Some believe that the focus on a forced fee market by major Bitcoin Core developers represents a conflict of interest since their employer is interested in pushing off-chain scaling solutions such as LN (more reading here).
Are there solutions in development that show the block sizes as proposed via BIP 101 are viable and block propagation times in particular are low enough?
[PSA] If your Bitcoin are not ready-to-transact in a wallet whose keys you exclusively control, then you don't control your Bitcoin (625 points, 216 comments)
Why us old-school Bitcoiners argue that Bitcoin Cash should be considered "the real Bitcoin" (585 points, 587 comments)
I think we need an EDA fix before the Nov hardfork (535 points, 346 comments)
Why large blocks: because one man's "coffee purchase transaction" is another man's monthly income (508 points, 104 comments)
There is a word for a "store of value" with no underlying utility, and that word is "collectible" (481 points, 171 comments)
Ripple user comes to defend Ripple, gets hundreds of upvotes, but can't answer the most fundamental question: what prevents inflation? (462 points, 407 comments)
If you don't agree that the mission is to make onchain transactions readily available to ALL people at ALL income levels then you don't understand the whole reason Bitcoin was invented to begin with (449 points, 203 comments)
Shutting down or restricting the uses of bank accounts, thereby forbidding clients to buy crypto, is a blatant affront to the rights of civil liberty, manifested, but not limited to, in the rights to private property and free speech (563 points, 262 comments)
I believe Bitcoin Core/Blockstream is now attempting to infiltrate Bitcoin Cash in the same manner that they did with Bitcoin Segwit. They are suddenly befriending Bitcoin Cash. Only in that way can they destroy from within. Do not be fooled. (405 points, 170 comments)
You have $100 worth of BTC. So you purchase an item for $66, but have to pay a $17 fee. Now you have $17 worth of Bitcoin left, but it costs $17 more to move it. So $66 item effectively cost you $100. #Thanks BlockStream (1427 points, 434 comments)
2028 points: kairepaire's comment in As of today, Steam will no longer support Bitcoin as a payment method
2019 points: vbuterin's comment in "So no worries, Ethereum's long term value is still ~0." -Greg Maxwell, CTO of Blockstream and opponent of allowing Bitcoin to scale as Satoshi had planned.
1210 points: vbuterin's comment in Vitalik Buterin tried to develop Ethereum on top of Bitcoin, but was stalled because the developers made it hard to build on top of Bitcoin. Vitalik only then built Ethereum as a separate currency
1205 points: LiamGaughan's comment in As of today, Steam will no longer support Bitcoin as a payment method
Gavin Andresen ist seit 2010 massgeblich für das Konzept der Kryptowährung Bitcoin verantwortlich und der führende Maintainer.Er gründete die Bitcoin Foundation. Andresen studierte an der Princeton University. Er arbeitete für TruCoin, University of Massachusetts Amherst und Gravity Switch. Gavin Andresen, Principal of the BitCoin Virtual Currency Project, talks with EconTalk host Russ Roberts about BitCoin, an innovative attempt to create a decentralized electronic currency. Andresen explains the origins of BitCoin, how new currency gets created, how you can acquire BitCoins and the prospects for BitCoin’s future. Can it compete with government-sanctioned money? Former lead bitcoin developer Gavin Andresen was hired by the foundation as "chief scientist."  In June 2013, the foundation received a letter from the California Department of Financial Institutions requesting that they "cease and desist from conducting the business of money transmission in this state,"  and again when it published their detailed response to the regulators. ... Gavin's ability to cut to the core *practical* ramifications of technical issues is a greatly needed skill in bitcoin dev, else we get the very narrow linear ultra-extrapolation thinking that's holding bitcoin core back. And on a technical note regarding the first point that Gavin refutes - Metcalfe's Law's n^2 scaling - it may be more reasonable to treat Metcalfe's Law as (n)log(n) for large ... Gavin Andresen on BitCoin and Virtual Currency (econtalk.org) 63 points by pointillistic on Apr 4, 2011 hide past web favorite 45 comments: sgornick on Apr 4, 2011. Best comment from the show's host: "I hope some of my colleagues will find this of interest." A decentralized, global currency is truly a foreign concept to economists. In the early 1990s there were many who immediately ...
Do Not Sell! Trust Me...You Need To Watch This. [Bitcoin Market Analysis]
Support MadBitcoins: 1PtAdf3LbwrPfX87dQ8TMuKEzuMUZtg1z1 April 8, 2014 -- Pittsburgh, Pennsylvania -- MadBitcoins: Head for the mountains. Madbitcoins Subscriber Index ... In 2010, Nakamoto handed the network alert key and control of the Bitcoin Core code repository over to Gavin Andresen, who later became lead developer at the Bitcoin Foundation. Nakamoto ... He then handed over control of the source code repository and network alert key to Gavin Andresen, transferred several related domains to various prominent members of the bitcoin community ... Gavin Andresen about Bitcoin - Duration: 16:09. WYONAPICTURES 4,468 views. 16:09. Is America right to fear Huawei? The Economist - Duration: 9:58. The Economist Recommended for you. New; 9:58 ... BITCOIN में INVESTMENT करें या नहीं I Complete Analysis I Dr Vivek Bindra - Duration: 13:38. Dr. Vivek Bindra: Motivational Speaker 3,430,531 views