If an attacker tries to create an alternative longest chain (e.g. double spend), are they *required* to re-mine all subsequent blocks after the one they alter *before* the network accepts the newest block?
Been thinking on this for hours to try and fully grasp mining, and this scenario is still confusing to me -- makes me realize I don't fundamentally grasp some concepts about mining. First, I understand that there is a shared criteria for the newest block (based on difficulty target?) that all miners have to go by in order to complete the SHA256 algorithm puzzle and win the latest block. However, I understand that all miners are separately targeting different specific numbers? And the number is informed by the specific transactions they choose to incorporate in their block, which informs the block hash(?) that they're trying to solve via bruteforcing the SHA256 algorithm? And finally when they do win the block they beam it to the network and other honest nodes accept it. (feel free to clarify if I'm not understanding that right) That said, I'm trying to understand if dishonest nodes can purposefully ignore other nodes with longer chains, and meanwhile work on an alternative timeline. Based on an article (see the "Why You Can't Cheat Bitcoin" diagram) , that to create an alternative history w/ a double spend in an altered block, the attacker would be required to recalculate all subsequent blocks... but they would have to complete them before everybody else in the network completed computing the newest block on the honest active longest chain, or else restart again (making it even harder for them). As I understand, this means they have to compute all their subsequent blocks in roughly 10 minutes, or otherwise restart... If this is true, why? Why can't the attacker ignore the latest chain? Why does an attacker restart every time another miner broadcasts that they found a new block / created the longest active chain? In other words, what prevents an attacker from altering a block 6+ blocks back and re-mining subsequent blocks at a rate slightly faster than the rest of the network -- meanwhile ignoring the network's newest blocks. In this theory, they should eventually overtake the network given enough time (and assuming they have the hash power to move this fast?)? Meaning, even as the network is averaging new blocks every 10 minutes, the attacker would still eventually catch up based on its faster mining rate and overcome the network, making it officially the longest chain and legitimizing its double spending history... Is something preventing them from doing this? On a related note regarding the factor of a miner altering the difficulty of mining in this scenario -- why is it that: "blocks released by malicious miners that do not meet the required difficulty target will simply be rejected by the other participants in the network." ? In other words, what specifically prevents an attacker (using only a small amount of total hash power) from changing past blocks and then mining subsequent blocks at an easier difficulty level than the rest of the network in order to quickly become the longest chain? Thanks in advance!!!  https://medium.com/loom-network/understanding-blockchain-fundamentals-part-2-proof-of-work-proof-of-stake-b6ae907c7edb  https://en.bitcoin.it/wiki/Mining edit: clarification / formatting
[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
I understand - at a meta-level - what Merkle trees are and how they are used by SPV clients. I don't understand a specific example from "Mastering Bitcoin". Diagram: https://imgur.com/gallery/nZY11ao/ In the image, there is a path of blue blocks for block "HK" (green). The blue blocks are an "authentication path" (according to the book). The path of blocks with dashes around them apparently prove to SPV clients that "HK" is in the block. The dashed blocks have a direct path from "HK" to the root hash. The blue blocks do not. I don't understand the point of the blue blocks. What do they do? How do they relate to the blocks with dashes? Thanks!
Diagram of a Bitcoin block - We present an illustration of a Bitcoin block, including the Merkle trees. We explain why the 2nd Merkle tree in the block is necessary. We then take a closer look at some of the negatives of both overt & covert AsicBoost
TL;DR: https://i.imgur.com/iu9hcIj.gif In this thread by Roger Ver I posted this comment. User CRAB_WHORE_SLAYER challenged me to provide a diagram in response. The problem is reality is messy and full of nuance, not lending itself to simple, clear and pretty diagrams that are also completely accurate. I'm also no graphic artist, so this is the resulting mash-up that I cobbled together. I'd welcome anyone skilled in graphics to clean this up. NOTE: For greater accuracy and completeness, I should mention there's actually a fourth block chain coming out of the August 2017 forks that is not displayed here: the original non-SegWit 1 MB BTC. That block chain is also now abandoned.
At about 150 members strong so far, the YFI project has attracted some of the top minds in crypto that have been invited to be part of the YFI Developer Community. This invitation to be part of this premier developer community is high praise IMO. We help the 5 main YFI Developers mentioned in the AMA yesterday, so that they can focus on development and testing, instead of doing the kinds of things YFI community managers like myself do, or one of the myriad other tasks the other ~140 community members do, to grow and improve the YFI ecosystem. This way: everyone's skills are utilized best so that we all can benefit. There are giants of crypto and DeFi in this YFI Developer Community quietly going about their business with little fanfare. There's people of all walks of life all over the world that have found themselves intrigued enough with the project to offer their time and skills. I think all of the members of this community wear at least 2-3 "hats" (multi-role members). Here is a partial list of the types of international developers and community members who are actively involved in the growth and expansion of the YFI ecosystem and DAO. I won't name names, as most are anonymous and you can get names of the first ~20 Devs listed further down in past subreddit posts, but you've seen some of them stop by from time to time. Your mods here are perfect examples of a typical, multi-role Dev Community member. It takes a village to raise a child. This is your global village raising this project from nothing but code and an idea:
Smart Contract Builders
Programmers of various languages
Traders and Strategists
Computer Science PhDs and Masters Degrees
Community Organizers / Managers / Moderators
Engineers of all stripes
Technicians of all types
Legal and Regulatory experts
Web site designers
"Jack of all trades" types
Hopefully I covered all of the main bases. If you're part of the YFI Dev Community, please say "Hi" and give a short description of your role(s), if you can. To give you an idea of the current size of the sub-teams, YFI's Documents team of technical writers such as myself, editors, and marketers group currently number 19 members. Our new YFI Communications Channel team of organizers, managers, volunteers and marketers meant to facilitate comms and consistent messaging is currently at 18 members. It's an honor to work with all of them. The amount of casual cross-collaboration with other giants of DeFi and crypto is simply unmatched, from what I've seen so far. The diagram I posted yesterday from the ZETA Protocol launch was a perfect example. I've worked in a number of crypto community start-ups dating back to 2013, and this is the biggest, most massive crypto project I've been involved with so far, reminding me of the early days of BTC when we thought we'd be buying coffee with Bitcoin by now, and there was only one Bitcoin.
Bitcoin is the world’s first cryptocurrency which works on a completely decentralized network known as the blockchain. The blockchain network consists a link of blocks that are secured using cryptography and record all the transactions. Bitcoin was first presented to the world in 2009 by an anonymous identity known as Satoshi Nakamoto. About Bitcoin Momentum. Network Momentum is a view created by Philip Swift which looks into the value transmitted through the Bitcoin blockchain denominated in BTC value plotted against Bitcoin`s price. It serves as a leading indicator of Bitcoin bull markets. Sufficiently high levels of value throughput is needed drive bull markets. Buy Bitcoin. Purchase Bitcoin using a credit card or with your linked bank account via an online exchange. Learn More. Use Bitcoin Cash (BCH) Send real money quickly to anywhere in the world, basically for free. Learn More. Play Games with Bitcoin Cash (BCH) Bitcoin Games is a provably fair gaming site. ... Bitcoin is changing the way people think about money by planting a seed of doubt in people’s minds — in a positive and thought-provoking way. Mind you, given the financial crises over the past decade, it’s understandable that some people are trying to come up with new and creative solutions for a better economy. Bitcoin, […] The total number of mined bitcoin that are currently circulating on the network. Market Price. The average USD market price across major bitcoin exchanges. Market Capitalization (USD) The total USD value of bitcoin in circulation. Exchange Trade Volume (USD)
The Puell Multiple is a very interesting Bitcoin chart which tells us something about the miners revenue in USD which represents the total selling pressure f... Learn how to read stock charts and identify technical patterns as ClayTrader does a quick stock chart review on Bitcoin (Bitcoin). Watch more Bitcoin Technical Analysis Videos: https://claytrader ... The Bitcoin Chart They DON'T Want You to See - Duration: 10:33. Alessio Rastani 78,116 views. 10:33. Language: English Location: United States Restricted Mode: Off History Help Let's talk about btc. Join me using these links. My website for the trade calls, indicators, and lessons. https://sharkcharts.live/ My Discord server https://discord.gg/Re4VXDt Here's my ... For Bitcoin, it is business as usual. Here we just take a look at where we are on our logarithmic regression chart, and also take note of the fact that despite the positive price movement, we are ...