submitted by j0j0r0 to ethereum [link] [comments]
Dragonchain Public Proposal TL;DR:Dragonchain has demonstrated twice Reddit’s entire total daily volume (votes, comments, and posts per Reddit 2019 Year in Review) in a 24-hour demo on an operational network. Every single transaction on Dragonchain is decentralized immediately through 5 levels of Dragon Net, and then secured with combined proof on Bitcoin, Ethereum, Ethereum Classic, and Binance Chain, via Interchain. At the time, in January 2020, the entire cost of the demo was approximately $25K on a single system (transaction fees locked at $0.0001/txn). With current fees (lowest fee $0.0000025/txn), this would cost as little as $625.
Watch Joe walk through the entire proposal and answer questions on YouTube.
This proposal is also available on the Dragonchain blog.
Hello Reddit and Ethereum community!I’m Joe Roets, Founder & CEO of Dragonchain. When the team and I first heard about The Great Reddit Scaling Bake-Off we were intrigued. We believe we have the solutions Reddit seeks for its community points system and we have them at scale.
For your consideration, we have submitted our proposal below. The team at Dragonchain and I welcome and look forward to your technical questions, philosophical feedback, and fair criticism, to build a scaling solution for Reddit that will empower its users. Because our architecture is unlike other blockchain platforms out there today, we expect to receive many questions while people try to grasp our project. I will answer all questions here in this thread on Reddit, and I've answered some questions in the stream on YouTube.
We have seen good discussions so far in the competition. We hope that Reddit’s scaling solution will emerge from The Great Reddit Scaling Bake-Off and that Reddit will have great success with the implementation.
Executive summaryDragonchain is a robust open source hybrid blockchain platform that has proven to withstand the passing of time since our inception in 2014. We have continued to evolve to harness the scalability of private nodes, yet take full advantage of the security of public decentralized networks, like Ethereum. We have a live, operational, and fully functional Interchain network integrating Bitcoin, Ethereum, Ethereum Classic, and ~700 independent Dragonchain nodes. Every transaction is secured to Ethereum, Bitcoin, and Ethereum Classic. Transactions are immediately usable on chain, and the first decentralization is seen within 20 seconds on Dragon Net. Security increases further to public networks ETH, BTC, and ETC within 10 minutes to 2 hours. Smart contracts can be written in any executable language, offering full freedom to existing developers. We invite any developer to watch the demo, play with our SDK’s, review open source code, and to help us move forward. Dragonchain specializes in scalable loyalty & rewards solutions and has built a decentralized social network on chain, with very affordable transaction costs. This experience can be combined with the insights Reddit and the Ethereum community have gained in the past couple of months to roll out the solution at a rapid pace.
Response and PoCIn The Great Reddit Scaling Bake-Off post, Reddit has asked for a series of demonstrations, requirements, and other considerations. In this section, we will attempt to answer all of these requests.
A live proof of concept showing hundreds of thousands of transactionsOn Jan 7, 2020, Dragonchain hosted a 24-hour live demonstration during which a quarter of a billion (250 million+) transactions executed fully on an operational network. Every single transaction on Dragonchain is decentralized immediately through 5 levels of Dragon Net, and then secured with combined proof on Bitcoin, Ethereum, Ethereum Classic, and Binance Chain, via Interchain. This means that every single transaction is secured by, and traceable to these networks. An attack on this system would require a simultaneous attack on all of the Interchained networks.
24 hours in 4 minutes (YouTube):
24 hours in 4 minutes
The demonstration was of a single business system, and any user is able to scale this further, by running multiple systems simultaneously. Our goals for the event were to demonstrate a consistent capacity greater than that of Visa over an extended time period.
Tooling to reproduce our demo is available here:
Source code (for on & off-chain components as well tooling used for the PoC). The source code does not have to be shared publicly, but if Reddit decides to use a particular solution it will need to be shared with Reddit at some point.
How it works & scales
Architectural ScalingDragonchain’s architecture attacks the scalability issue from multiple angles. Dragonchain is a hybrid blockchain platform, wherein every transaction is protected on a business node to the requirements of that business or purpose. A business node may be held completely private or may be exposed or replicated to any level of exposure desired.
Every node has its own blockchain and is independently scalable. Dragonchain established Context Based Verification as its consensus model. Every transaction is immediately usable on a trust basis, and in time is provable to an increasing level of decentralized consensus. A transaction will have a level of decentralization to independently owned and deployed Dragonchain nodes (~700 nodes) within seconds, and full decentralization to BTC and ETH within minutes or hours. Level 5 nodes (Interchain nodes) function to secure all transactions to public or otherwise external chains such as Bitcoin and Ethereum. These nodes scale the system by aggregating multiple blocks into a single Interchain transaction on a cadence. This timing is configurable based upon average fees for each respective chain. For detailed information about Dragonchain’s architecture, and Context Based Verification, please refer to the Dragonchain Architecture Document.
Economic ScalingAn interesting feature of Dragonchain’s network consensus is its economics and scarcity model. Since Dragon Net nodes (L2-L4) are independent staking nodes, deployment to cloud platforms would allow any of these nodes to scale to take on a large percentage of the verification work. This is great for scalability, but not good for the economy, because there is no scarcity, and pricing would develop a downward spiral and result in fewer verification nodes. For this reason, Dragonchain uses TIME as scarcity.
TIME is calculated as the number of Dragons held, multiplied by the number of days held. TIME influences the user’s access to features within the Dragonchain ecosystem. It takes into account both the Dragon balance and length of time each Dragon is held. TIME is staked by users against every verification node and dictates how much of the transaction fees are awarded to each participating node for every block.
TIME also dictates the transaction fee itself for the business node. TIME is staked against a business node to set a deterministic transaction fee level (see transaction fee table below in Cost section). This is very interesting in a discussion about scaling because it guarantees independence for business implementation. No matter how much traffic appears on the entire network, a business is guaranteed to not see an increased transaction fee rate.
Scaled DeploymentDragonchain uses Docker and Kubernetes to allow the use of best practices traditional system scaling. Dragonchain offers managed nodes with an easy to use web based console interface. The user may also deploy a Dragonchain node within their own datacenter or favorite cloud platform. Users have deployed Dragonchain nodes on-prem on Amazon AWS, Google Cloud, MS Azure, and other hosting platforms around the world. Any executable code, anything you can write, can be written into a smart contract. This flexibility is what allows us to say that developers with no blockchain experience can use any code language to access the benefits of blockchain. Customers have used NodeJS, Python, Java, and even BASH shell script to write smart contracts on Dragonchain.
With Docker containers, we achieve better separation of concerns, faster deployment, higher reliability, and lower response times.
We chose Kubernetes for its self-healing features, ability to run multiple services on one server, and its large and thriving development community. It is resilient, scalable, and automated. OpenFaaS allows us to package smart contracts as Docker images for easy deployment.
Contract deployment time is now bounded only by the size of the Docker image being deployed but remains fast even for reasonably large images. We also take advantage of Docker’s flexibility and its ability to support any language that can run on x86 architecture. Any image, public or private, can be run as a smart contract using Dragonchain.
Flexibility in ScalingDragonchain’s architecture considers interoperability and integration as key features. From inception, we had a goal to increase adoption via integration with real business use cases and traditional systems.
We envision the ability for Reddit, in the future, to be able to integrate alternate content storage platforms or other financial services along with the token.
Cost estimates (on-chain and off-chain) For the purpose of this proposal, we assume that all transactions are on chain (posts, replies, and votes).On the Dragonchain network, transaction costs are deterministic/predictable. By staking TIME on the business node (as described above) Reddit can reduce transaction costs to as low as $0.0000025 per transaction.
Dragonchain Fees Table
How to run itBuilding on Dragonchain is simple and requires no blockchain experience. Spin up a business node (L1) in our managed environment (AWS), run it in your own cloud environment, or on-prem in your own datacenter. Clear documentation will walk you through the steps of spinning up your first Dragonchain Level 1 Business node.
Getting started is easy...
ArchitectureDragonchain is an open source hybrid platform. Through Dragon Net, each chain combines the power of a public blockchain (like Ethereum) with the privacy of a private blockchain.
Dragonchain organizes its network into five separate levels. A Level 1, or business node, is a totally private blockchain only accessible through the use of public/private keypairs. All business logic, including smart contracts, can be executed on this node directly and added to the chain.
After creating a block, the Level 1 business node broadcasts a version stripped of sensitive private data to Dragon Net. Three Level 2 Validating nodes validate the transaction based on guidelines determined from the business. A Level 3 Diversity node checks that the level 2 nodes are from a diverse array of locations. A Level 4 Notary node, hosted by a KYC partner, then signs the validation record received from the Level 3 node. The transaction hash is ledgered to the Level 5 public chain to take advantage of the hash power of massive public networks.
Dragon Net can be thought of as a “blockchain of blockchains”, where every level is a complete private blockchain. Because an L1 can send to multiple nodes on a single level, proof of existence is distributed among many places in the network. Eventually, proof of existence reaches level 5 and is published on a public network.
APIs (on chain & off)
Known issues or tradeoffs
Costs and resources
Summary of cost & resource information for both on-chain & off-chain components used in the PoC, as well as cost & resource estimates for further scaling. If your PoC is not on mainnet, make note of any mainnet caveats (such as congestion issues).Every transaction on the PoC system had a transaction fee of $0.0001 (one-hundredth of a cent USD). At 256MM transactions, the demo cost $25,600. With current operational fees, the same demonstration would cost $640 USD.
For the demonstration, to achieve throughput to mimic a worldwide payments network, we modeled several clients in AWS and 4-5 business nodes to handle the traffic. The business nodes were tuned to handle higher throughput by adjusting memory and machine footprint on AWS. This flexibility is valuable to implementing a system such as envisioned by Reddit. Given that Reddit’s daily traffic (posts, replies, and votes) is less than half that of our demo, we would expect that the entire Reddit system could be handled on 2-5 business nodes using right-sized containers on AWS or similar environments.
Verification was accomplished on the operational Dragon Net network with over 700 independently owned verification nodes running around the world at no cost to the business other than paid transaction fees.
This PoC should scale to the numbers below with minimal costs (both on & off-chain). There should also be a clear path to supporting hundreds of millions of users.During Dragonchain’s 24 hour demo, the above required numbers were reached within the first few minutes.
Reddit’s total activity is 9000% more than Ethereum’s total transaction level. Even if you do not include votes, it is still 700% more than Ethereum’s current volume. Dragonchain has demonstrated that it can handle 250 million transactions a day, and it’s architecture allows for multiple systems to work at that level simultaneously. In our PoC, we demonstrate double the full capacity of Reddit, and every transaction was proven all the way to Bitcoin and Ethereum.
Reddit Scaling on Ethereum
Solutions should not depend on any single third-party provider. We prefer solutions that do not depend on specific entities such as Reddit or another provider, and solutions with no single point of control or failure in off-chain components but recognize there are numerous trade-offs to considerDragonchain’s architecture calls for a hybrid approach. Private business nodes hold the sensitive data while the validation and verification of transactions for the business are decentralized within seconds and secured to public blockchains within 10 minutes to 2 hours. Nodes could potentially be controlled by owners of individual subreddits for more organic decentralization.
Usability Scaling solutions should have a simple end user experience.
Users shouldn't have to maintain any extra state/proofs, regularly monitor activity, keep track of extra keys, or sign anything other than their normal transactionsDragonchain and its customers have demonstrated extraordinary usability as a feature in many applications, where users do not need to know that the system is backed by a live blockchain. Lyceum is one of these examples, where the progress of academy courses is being tracked, and successful completion of courses is rewarded with certificates on chain. Our @Save_The_Tweet bot is popular on Twitter. When used with one of the following hashtags - #please, #blockchain, #ThankYou, or #eternalize the tweet is saved through Eternal to multiple blockchains. A proof report is available for future reference. Other examples in use are DEN, our decentralized social media platform, and our console, where users can track their node rewards, view their TIME, and operate a business node.
Transactions complete in a reasonable amount of time (seconds or minutes, not hours or days)All transactions are immediately usable on chain by the system. A transaction begins the path to decentralization at the conclusion of a 5-second block when it gets distributed across 5 separate community run nodes. Full decentralization occurs within 10 minutes to 2 hours depending on which interchain (Bitcoin, Ethereum, or Ethereum Classic) the transaction hits first. Within approximately 2 hours, the combined hash power of all interchained blockchains secures the transaction.
Free to use for end users (no gas fees, or fixed/minimal fees that Reddit can pay on their behalf)With transaction pricing as low as $0.0000025 per transaction, it may be considered reasonable for Reddit to cover transaction fees for users.
All of Reddit's Transactions on Blockchain (month)
Community points can be earned by users and distributed directly to their Reddit account in batch (as per Reddit minting plan), and allow users to withdraw rewards to their Ethereum wallet whenever they wish. Withdrawal fees can be paid by either user or Reddit. This model has been operating inside the Dragonchain system since 2018, and many security and financial compliance features can be optionally added. We feel that this capability greatly enhances user experience because it is seamless to a regular user without cryptocurrency experience, yet flexible to a tech savvy user. With regard to currency or token transactions, these would occur on the Reddit network, verified to BTC and ETH. These transactions would incur the $0.0000025 transaction fee. To estimate this fee we use the monthly active Reddit users statista with a 60% adoption rate and an estimated 10 transactions per month average resulting in an approximate $720 cost across the system. Reddit could feasibly incur all associated internal network charges (mining/minting, transfer, burn) as these are very low and controllable fees.
Reddit Internal Token Transaction Fees
Reddit Ethereum Token Transaction Fees
When we consider further the Ethereum fees that might be incurred, we have a few choices for a solution.
Users should be able to view their balances & transactions via a blockchain explorer-style interfaceFrom interfaces for users who have no knowledge of blockchain technology to users who are well versed in blockchain terms such as those present in a typical block explorer, a system powered by Dragonchain has flexibility on how to provide balances and transaction data to users. Transactions can be made viewable in an Eternal Proof Report, which displays raw data along with TIME staking information and traceability all the way to Bitcoin, Ethereum, and every other Interchained network. The report shows fields such as transaction ID, timestamp, block ID, multiple verifications, and Interchain proof. See example here.
Node payouts within the Dragonchain console are listed in chronological order and can be further seen in either Dragons or USD. See example here.
In our social media platform, Dragon Den, users can see, in real-time, their NRG and MTR balances. See example here.
A new influencer app powered by Dragonchain, Raiinmaker, breaks down data into a user friendly interface that shows coin portfolio, redeemed rewards, and social scores per campaign. See example here.
Exiting is fast & simpleWithdrawing funds on Dragonchain’s console requires three clicks, however, withdrawal scenarios with more enhanced security features per Reddit’s discretion are obtainable.
Interoperability Compatibility with third party apps (wallets/contracts/etc) is necessary.Proven interoperability at scale that surpasses the required specifications. Our entire platform consists of interoperable blockchains connected to each other and traditional systems. APIs are well documented. Third party permissions are possible with a simple smart contract without the end user being aware. No need to learn any specialized proprietary language. Any code base (not subsets) is usable within a Docker container. Interoperable with any blockchain or traditional APIs. We’ve witnessed relatively complex systems built by engineers with no blockchain or cryptocurrency experience. We’ve also demonstrated the creation of smart contracts within minutes built with BASH shell and Node.js. Please see our source code and API documentation.
Scaling solutions should be extensible and allow third parties to build on top of it Open source and extensible
Documentation should be clear and completeFor full documentation, explore our docs, SDK’s, Github repo’s, architecture documents, original Disney documentation, and other links or resources provided in this proposal.
Third-party permissionless integrations should be possible & straightforward Smart contracts are Docker based, can be written in any language, use full language (not subsets), and can therefore be integrated with any system including traditional system APIs. Simple is better. Learning an uncommon or proprietary language should not be necessary.Advanced knowledge of mathematics, cryptography, or L2 scaling should not be required. Compatibility with common utilities & toolchains is expected.
Dragonchain business nodes and smart contracts leverage Docker to allow the use of literally any language or executable code. No proprietary language is necessary. We’ve witnessed relatively complex systems built by engineers with no blockchain or cryptocurrency experience. We’ve also demonstrated the creation of smart contracts within minutes built with BASH shell and Node.js.
Bonus Points: Show us how it works. Do you have an idea for a cool new use case for Community Points? Build it!
TIMECommunity points could be awarded to Reddit users based upon TIME too, whereas the longer someone is part of a subreddit, the more community points someone naturally gained, even if not actively commenting or sharing new posts. A daily login could be required for these community points to be credited. This grants awards to readers too and incentivizes readers to create an account on Reddit if they browse the website often. This concept could also be leveraged to provide some level of reputation based upon duration and consistency of contribution to a community subreddit.
Dragon DenDragonchain has already built a social media platform that harnesses community involvement. Dragon Den is a decentralized community built on the Dragonchain blockchain platform. Dragon Den is Dragonchain’s answer to fake news, trolling, and censorship. It incentivizes the creation and evaluation of quality content within communities. It could be described as being a shareholder of a subreddit or Reddit in its entirety. The more your subreddit is thriving, the more rewarding it will be. Den is currently in a public beta and in active development, though the real token economy is not live yet. There are different tokens for various purposes. Two tokens are Lair Ownership Rights (LOR) and Lair Ownership Tokens (LOT). LOT is a non-fungible token for ownership of a specific Lair. LOT will only be created and converted from LOR.
Energy (NRG) and Matter (MTR) work jointly. Your MTR determines how much NRG you receive in a 24-hour period. Providing quality content, or evaluating content will earn MTR.
Security. Users have full ownership & control of their points.All community points awarded based upon any type of activity or gift, are secured and provable to all Interchain networks (currently BTC, ETH, ETC). Users are free to spend and withdraw their points as they please, depending on the features Reddit wants to bring into production.
Balances and transactions cannot be forged, manipulated, or blocked by Reddit or anyone elseUsers can withdraw their balance to their ERC20 wallet, directly through Reddit. Reddit can cover the fees on their behalf, or the user covers this with a portion of their balance.
Users should own their points and be able to get on-chain ERC20 tokens without permission from anyone elseThrough our console users can withdraw their ERC20 rewards. This can be achieved on Reddit too. Here is a walkthrough of our console, though this does not show the quick withdrawal functionality, a user can withdraw at any time. https://www.youtube.com/watch?v=aNlTMxnfVHw
Points should be recoverable to on-chain ERC20 tokens even if all third-parties involved go offlineIf necessary, signed transactions from the Reddit system (e.g. Reddit + Subreddit) can be sent to the Ethereum smart contract for minting.
A public, third-party review attesting to the soundness of the design should be availableTo our knowledge, at least two large corporations, including a top 3 accounting firm, have conducted positive reviews. These reviews have never been made public, as Dragonchain did not pay or contract for these studies to be released.
Bonus pointsSee above
Compatibility with HSMs & hardware walletsFor the purpose of this proposal, all tokenization would be on the Ethereum network using standard token contracts and as such, would be able to leverage all hardware wallet and Ethereum ecosystem services.
Minting/distributing tokens is not performed by Reddit directlyThis operation can be automated by smart contract on Ethereum. Subreddits can if desired have a role to play.
One off point burning, as well as recurring, non-interactive point burning (for subreddit memberships) should be possible and scalableThis is possible and scalable with interaction between Dragonchain Reddit system and Ethereum token contract(s).
Fully open-source solutions are strongly preferredDragonchain is fully open source (see section on Disney release after conclusion).
ConclusionWhether it is today, or in the future, we would like to work together to bring secure flexibility to the highest standards. It is our hope to be considered by Ethereum, Reddit, and other integrative solutions so we may further discuss the possibilities of implementation. In our public demonstration, 256 million transactions were handled in our operational network on chain in 24 hours, for the low cost of $25K, which if run today would cost $625. Dragonchain’s interoperable foundation provides the atmosphere necessary to implement a frictionless community points system. Thank you for your consideration of our proposal. We look forward to working with the community to make something great!
Disney Releases Blockchain Platform as Open SourceThe team at Disney created the Disney Private Blockchain Platform. The system was a hybrid interoperable blockchain platform for ledgering and smart contract development geared toward solving problems with blockchain adoption and usability. All objective evaluation would consider the team’s output a success. We released a list of use cases that we explored in some capacity at Disney, and our input on blockchain standardization as part of our participation in the W3C Blockchain Community Group.
Open SourceIn 2016, Roets proposed to release the platform as open source to spread the technology outside of Disney, as others within the W3C group were interested in the solutions that had been created inside of Disney.
Following a long process, step by step, the team met requirements for release. Among the requirements, the team had to:
The Disney Open Source Committee approved the application known as OSSRELEASE-10, and the code was released on October 2, 2016. Disney decided to not issue a press release.
Original OSSRELASE-10 document
Dragonchain FoundationThe Dragonchain Foundation was created on January 17, 2017. https://den.social/l/Dragonchain/24130078352e485d96d2125082151cf0/dragonchain-and-disney/
Contentssubmitted by D-platform to u/D-platform [link] [comments]
Proof of Work (commonly abbreviated to PoW) is a mechanism for preventing double-spends. Most major cryptocurrencies use this as their consensus algorithm. That’s just what we call a method for securing the cryptocurrency’s ledger.
Proof of Work was the first consensus algorithm to surface, and, to date, remains the dominant one. It was introduced by Satoshi Nakamoto in the 2008 Bitcoin white paper, but the technology itself was conceived long before then.
Adam Back’s HashCash is an early example of a Proof of Work algorithm in the pre-cryptocurrency days. By requiring senders to perform a small amount of computing before sending an email, receivers could mitigate spam. This computation would cost virtually nothing to a legitimate sender, but quickly add up for someone sending emails en masse.
What is a double-spend?A double-spend occurs when the same funds are spent more than once. The term is used almost exclusively in the context of digital money — after all, you’d have a hard time spending the same physical cash twice. When you pay for a coffee today, you hand cash over to a cashier who probably locks it in a register. You can’t go to the coffee shop across the road and pay for another coffee with the same bill.
In digital cash schemes, there’s the possibility that you could. You’ve surely duplicated a computer file before — you just copy and paste it. You can email the same file to ten, twenty, fifty people.
Since digital money is just data, you need to prevent people from copying and spending the same units in different places. Otherwise, your currency will collapse in no time.
For a more in-depth look at double-spending, check out Double Spending Explained.
Why is Proof of Work necessary?If you’ve read our guide to blockchain technology, you’ll know that users broadcast transactions to the network. Those transactions aren’t immediately considered valid, though. That only happens when they get added to the blockchain.
The blockchain is a big database that every user can see, so they can check if funds have been spent before. Picture it like this: you and three friends have a notepad. Anytime one of you wants to make a transfer of whatever units you’re using, you write it down — Alice pays Bob five units, Bob pays Carol two units, etc.
There’s another intricacy here — each time you make a transaction, you refer to the transaction where the funds came from. So, if Bob was paying Carol with two units, the entry would actually look like the following: Bob pays Carol two units from this earlier transaction with Alice.
Now, we have a way to track the units. If Bob tries to make another transaction using the same units he just sent to Carol, everyone will know immediately. The group won’t allow the transaction to be added to the notepad.
Now, this might work well in a small group. Everyone knows each other, so they’ll probably agree on which of the friends should add transactions to the notepad. What if we want a group of 10,000 participants? The notepad idea doesn’t scale well, because nobody wants to trust a stranger to manage it.
This is where Proof of Work comes in. It ensures that users aren’t spending money that they don’t have the right to spend. By using a combination of game theory and cryptography, a PoW algorithm enables anyone to update the blockchain according to the rules of the system.
How does PoW work?Our notepad above is the blockchain. But we don’t add transactions one by one — instead, we lump them into blocks. We announce the transactions to the network, then users creating a block will include them in a candidate block. The transactions will only be considered valid once their candidate block becomes a confirmed block, meaning that it has been added to the blockchain.
Appending a block isn’t cheap, however. Proof of Work requires that a miner (the user creating the block) uses up some of their own resources for the privilege. That resource is computing power, which is used to hash the block’s data until a solution to a puzzle is found.
Hashing the block’s data means that you pass it through a hashing function to generate a block hash. The block hash works like a “fingerprint” — it’s an identity for your input data and is unique to each block.
It’s virtually impossible to reverse a block hash to get the input data. Knowing an input, however, it’s trivial for you to confirm that the hash is correct. You just have to submit the input through the function and check if the output is the same.
In Proof of Work, you must provide data whose hash matches certain conditions. But you don’t know how to get there. Your only option is to pass your data through a hash function and to check if it matches the conditions. If it doesn’t, you’ll have to change your data slightly to get a different hash. Changing even one character in your data will result in a totally different result, so there’s no way of predicting what an output might be.
As a result, if you want to create a block, you’re playing a guessing game. You typically take information on all of the transactions that you want to add and some other important data, then hash it all together. But since your dataset won’t change, you need to add a piece of information that is variable. Otherwise, you would always get the same hash as output. This variable data is what we call a nonce. It’s a number that you’ll change with every attempt, so you’re getting a different hash every time. And this is what we call mining.
Summing up, mining is the process of gathering blockchain data and hashing it along with a nonce until you find a particular hash. If you find a hash that satisfies the conditions set out by the protocol, you get the right to broadcast the new block to the network. At this point, the other participants of the network update their blockchains to include the new block.
For major cryptocurrencies today, the conditions are incredibly challenging to satisfy. The higher the hash rate on the network, the more difficult it is to find a valid hash. This is done to ensure that blocks aren’t found too quickly.
As you can imagine, trying to guess massive amounts of hashes can be costly on your computer. You’re wasting computational cycles and electricity. But the protocol will reward you with cryptocurrency if you find a valid hash.
Let’s recap what we know so far:
That’s where public-key cryptography comes in. We won’t go into depth in this article, but check out What is Public-Key Cryptography? for a comprehensive look at it. In short, we use some neat cryptographic tricks that allow any user to verify whether someone has a right to move the funds they’re attempting to spend.
When you create a transaction, you sign it. Anyone on the network can compare your signature with your public key, and check whether they match. They’ll also check if you can actually spend your funds and that the sum of your inputs is higher than the sum of your outputs (i.e., that you’re not spending more than you have).
Any block that includes an invalid transaction will be automatically rejected by the network. It’s expensive for you to even attempt to cheat. You’ll waste your own resources without any reward.
Therein lies the beauty of Proof of Work: it makes it expensive to cheat, but profitable to act honestly. Any rational miner will be seeking ROI, so they can be expected to behave in a way that guarantees revenue.
Proof of Work vs. Proof of StakeThere are many consensus algorithms, but one of the most highly-anticipated ones is Proof of Stake (PoS). The concept dates back to 2011, and has been implemented in some smaller protocols. But it has yet to see adoption in any of the big blockchains.
In Proof of Stake systems, miners are replaced with validators. There’s no mining involved and no race to guess hashes. Instead, users are randomly selected — if they’re picked, they must propose (or “forge”) a block. If the block is valid, they’ll receive a reward made up of the fees from the block’s transactions.
Not just any user can be selected, though — the protocol chooses them based on a number of factors. To be eligible, participants must lock up a stake, which is a predetermined amount of the blockchain’s native currency. The stake works like bail: just as defendants put up a large sum of money to disincentivize them from skipping trial, validators lock up a stake to disincentivize cheating. If they act dishonestly, their stake (or a portion of it) will be taken.
Proof of Stake does have some benefits over Proof of Work. The most notable one is the smaller carbon footprint — since there’s no need for high-powered mining farms in PoS, the electricity consumed is only a fraction of that consumed in PoW.
That said, it has nowhere near the track record of PoW. Although it could be perceived as wasteful, mining is the only consensus algorithm that’s proven itself at scale. In just over a decade, it has secured trillions of dollars worth of transactions. To say with certainty whether PoS can rival its security, staking needs to be properly tested in the wild.
Closing thoughtsProof of Work was the original solution to the double-spend problem and has proven to be reliable and secure. Bitcoin proved that we don’t need centralized entities to prevent the same funds from being spent twice. With clever use of cryptography, hash functions, and game theory, participants in a decentralized environment can agree on the state of a financial database.
submitted by liuidaxmn to u/liuidaxmn [link] [comments]
Chinese Encryption Law To Come Into Force Next January China has passed the Encryption Law during the 14th session of the 13th National People’s Congress (NPC) on Oct 26, which will take effect on January 1, 2020.
Libra’s Threat To Central Banks Raises Questions About Its Launch According to AMBCrypto, Beatrice Weder di Mauro, President of the Centre for Economic Policy Research, is the latest think-tank professional to shed some light on Libra’s positive impact. In a recent interview with CNBC, di Mauro admitted that Libra may not receive a green light from lawmakers, adding that it had however managed to sow the seed for the introduction of another global digital currency.
YI Huanhuan: There Will Be National-Level Digital Bank, Digital Asset Exchange, Digital Investment Bank And Digital Asset Management Services Beijing Financial Association Research Institute Dean Yi Huanhuan commented on this politburo study session. YI has made nine predictions on governments’ action and industrial trend based on XI’s remarks. 1. The Cyberspace Administration will likely oversee this [blockchain] field; 2. To establish a national association of blockchain; 3. A large number of blockchain pilots will appear first in the financial industry, and then in government administrations; 4. Chinese national digital currency will play an important role in the world; 5. There will be state level digital banks, digital asset exchanges, digital investment banks and digital asset management; 6. The global blockchain network standards are likely to be set by China; 7. China will generate a large number of world-class leaders, entrepreneurs, and scholars in blockchain; 8. The performance of blockchain will be improved significantly in the next three to five years; 9. Mathematics, cryptography, and computational theory will become the most popular subjects.
Former Deputy Of BOC Governor: China has high blockchain visions, but should be careful with the trading risks and speculations Former Deputy Governor Of Bank Of China WANG Yongli shared his thought with CoinNess that China shows its ambition of establishing a leading global position in blockchain by researching and developing blockchain technology and applications. However, the blockchain technology is on an initial development stage. He urges investors to be careful with the trading risks and speculations as the definition of blockchain hasn’t been clarified, and there are existing issues like “decentralisation, security, high energy consumption” to be solved.
Video Lessons Targeting Blockchain Technology Go Live On CCPPD’s Platform Following the news that XI Jinping, Chinese President and General Secretary of the Communist Party of China, addressed the importance of blockchain in making technological breakthroughs at the eighteenth group learning event organized by the Political Bureau of the Central Committee Oct 24, the Xuexi.cn platform led by the Publicity Department of the Central Committee of the Communist Party of China, or CCPPD, announced Oct 26 the launch of the video lessons targeting the blockchain technology. The videos with a total of 25 lessons mainly include the preliminary introduction to the blockchain technology, the consensus agreement, Bitcoin, Ethereum and smart contracts, blockchain performance improvement, blockchain security, the basic knowledge of big data, in-depth analysis of blockchain instances, as well as the concrete programming code examples.
Encrypted project calendar（October 26, 2019）
KAT/Kambria: Kambria (KAT) Kambria will host the 2019 Southern California Artificial Intelligence and Data Science Conference in Los Angeles on October 26th with IDEAS. BTC/Bitcoin: CoinAgenda Global Summit will be held in Las Vegas from October 26th to 28th Horizen (ZEN): 26 October 2019 (or earlier) ZEN 2.0.19 Upgrade Zen 2.0.19 upgrade at block #610000, which is expected around October 26. IOTA (MIOTA): 26 October 2019 Taipei Workshop “Sam Chen, our Software Engineer, will explain how to use IOTA C Client library & will demonstrate 3 IoT projects running on ESP32 at…” Streamr DATAcoin (DATA): 26 October 2019 Data Union Demonstration “This Saturday, Streamr will hold the first demonstration of data unions, with a community built plugin for users to crowdsell…”
Encrypted project calendar（October 27, 2019）
ICON (ICX): 27 October 2019 Money 20/20 USA Event Money 20/20 USA in Las Vegas from October 27–30. Aeternity (AE): and 5 others 27 October 2019 CoinAgenda Conference CoinAgenda conference in Las Vegas from October 26–28.
Encrypted project calendar（October 28, 2019）
LTC/Litecoin: Litecoin (LTC) 2019 Litecoin Summit will be held from October 28th to October 29th in Las Vegas, USA BTC/Bitcoin: Mt.Gox changes the debt compensation plan submission deadline to October 28 ZEC/Zcash: Zcash (ZEC) will activate the Blossom Agreement on October 28th Stellar (XLM): 28 October 2019 Protocol 12 Upgrade Vote Horizon v0.22.0 has been released, which supports Protocol 12. This gives everyone ample time to prepare for the Protocol 12 upgrade vote Celsius (CEL) and 3 others: 28 October 2019 Litecoin Summit “…The Litecoin Summit offers two fun, jam-packed days with something for everyone.” XFOC (XFOC): The IDAX platform will be online XFOC and will open the XFOC/USDT trading pair at 13:00 on October 28. MEDIUM (MDM): The IDAX platform lists MDM and will open MDM/BTC trading pairs on October 28th at 15:00. ZB/ ZB Blockchain: The “2019 Hamburg Intercontinental Dialogue Conference” hosted by ZB.com will be held from October 28th to November 9th at the Four Seasons Hotel Hamburg, Germany. BQT (BQTX)： 28 October 2019 Down for Maintenance BQTX.com will be down for maintenance on the 28th of October from 7 to 12am UTC.
Encrypted project calendar（October 29, 2019）
BTC/Bitcoin: The 2nd World Encryption Conference (WCC) will be held in Las Vegas from October 29th to 31st. ICON (ICX): 29 October 2019 Decentralization “As a result, the decentralization schedule of the ICON Network has been changed from September 24, 2019 to October 29, 2019.” Ark (ARK): and 10 others 29 October 2019 WCC 2019 Second annual Blockchain and Cryptocurrency Technology event, World Crypto Conference (WCC), October 29th — October 31, 2019. Insifa (ISF): 29 October 2019 Prototype Alpha “We from Insifa have decided to be more open. Our Prototype will be developed in scrum. This means new releases every two weeks.” Enjin Coin (ENJ): 29 October 2019 EnjinCraft Stress Test “Join us Oct. 29 at 7:00pm GMT for a stress test. Let’s try to break #EnjinCraft!” IOTA (MIOTA): 29 October 2019 IOTSWC Barcelona IOT Solutions World Congress Digitalizing Industries conference in Barcelona from October 29–31.
Encrypted project calendar（October 30, 2019）
MIOTA/IOTA: IOTA (MIOTA) IOTA will host a community event on October 30th at the University of Southern California in Los Angeles on the topic “How to store data on IOTA Tangle.” TRON (TRX): 30 October 2019 SFBW19 Afterparty “TRON Official SFBW19 Afterparty from 7–10:30 PM in San Francisco.” Horizen (ZEN): 30 October 2019 Horizen Quarterly Update Join our first Quarterly Update on October the 30th at 5 PM UTC/ 1 PM EST. Deeper look into Engineering, BD, Marketing, and more. Aeternity (AE): 30 October 2019 Hardfork “The third hardfork of the æternity Mainnet is scheduled for October 30, 2019.” Valor Token (VALOR): 30 October 2019 Transaction Fees Resume “It’s September and the SMART VALOR Platform is still waiving transaction fees for all members, until October 30th!” Aragon (ANT): 30 October 2019 Singapore Meetup “Aragon on DAOs and DeFi” from 6:30–8:30 PM. Kambria (KAT): 30 October 2019 Outliers Hashed Awards Outliers Hashed awards from October 30–31. Ethereum Classic (ETC): 30 October 2019 Cohort Demo Day “ETC Labs hosts it’s 2nd Cohort Demo Day. Learn about the companies and project being accelerated through the Ethereum Classic ecosystem.”
Encrypted project calendar（October 31, 2019）
Spendcoin (SPND): 31 October 2019 (or earlier) Cross Ledger Mainnet “Cross Ledger Mainnet Release and SPND Token Swap,” during October 2019. Spendcoin (SPND): 31 October 2019 (or earlier) Blkchn University Beta “Blockchain University Beta goes live,” during October 2019. Stellar (XLM): 31 October 2019 (or earlier) Minor Release “We will have 6 Minor Releases in 2019; one each in February, March, May, June, August, and October.” Bitcoin SV (BSV): 31 October 2019 (or earlier) BSV Conference Seoul No additional information. Seele (SEELE): 31 October 2019 (or earlier) Public Network Mainne launch has been moved to Oct 31 . Howdoo (UDOO): 31 October 2019 (or earlier) Howdoo Live on Huawei Howdoo begins its exciting partnership with Huawei with listing as a featured app starting in October. Chiliz (CHZ): 31 October 2019 (or earlier) App Soft Launch Soft launch of Socios App by end of October. Dent (DENT): 31 October 2019 (or earlier) Loyalty Program “Afterburner loyalty program launch for all 21,6 Million mobile #DENT users will be in October!” IceChain (ICHX): 31 October 2019 (or earlier) Wallet Release IceChain releases wallet during October. Chiliz (CHZ): 31 October 2019 (or earlier) New Partnerships New sports and new teams joining Socios (+more updates and events) will be announced in the upcoming weeks. Horizen (ZEN): 31 October 2019 Weekly Insider Team updates at 3:30 PM UTC/ 11:30 AM EDT: Engineering, Node network, Product/UX, Helpdesk, Legal, BD, Marketing, CEO Closing thoughts, AMA. PCHAIN (PI): 31 October 2019 (or earlier) New Website No additional information. IOST (IOST): 31 October 2019 (or earlier) New Game on IOST “Eternal Fafnir, a new role-playing game developed by INFUN is coming to you in Oct.” Achain (ACT)： 31 October 2019 Mainnet 2.0 Launch “… The main network is officially scheduled to launch on October 31.” Mithril (MITH)：31 October 2019 Burn “MITH burn will take place on 2019/10/31 2pm UTC+8. “ Aergo (AERGO)： 31 October 2019 (or earlier) Aergo Lite V1.0 Release AergoLite, which brings blockchain compatibility to billions of devices using SQLite, released during October 2019. TE-FOOD (TFD)： 31 October 2019 (or earlier) Complementary Product “Development of a new, complementary product with a new partner, which we hope to be launched in September-October.” Edge (DADI)： 31 October 2019 (or earlier) Full Open Source Code base for the network fully open-sourced in September or October. BlockStamp (BST)： 31 October 2019 (or earlier) ASIC Miner Prototype In orderr to ensure BlockStamps continued decentralization, we will release a BST ASIC miner for testing. Perlin (PERL)： 31 October 2019 (or earlier) SSA Partnership “Perlin has partnered with the Singapore Shipping Association to create the International E-Registry of Ships (IERS)” Skrumble Network (SKM)： 31 October 2019 (or earlier) Exchange Release “3rd dApp: Exchange Release,” during October 2019. EDC Blockchain (EDC)： 31 October 2019 (or earlier) Blockchain Marketplace “As you already know, our ECRO blockchain marketplace is ready for release, and will open to the global community in October!” BlockStamp (BST)： 31 October 2019 (or earlier) ASIC Miner Prototype In orderr to ensure BlockStamps continued decentralization, we will release a BST ASIC miner for testing. XinFin Network (XDCE)： 31 October 2019 Homebloc Webinar “XinFin — Homebloc Webinar 2019” from 9–10 PM. Akropolis (AKRO)： 31 October 2019 (or earlier) Alpha Release “Delivers the initial mainnet implementation of protocol. All building blocks will be united to one product.” Hyperion (HYN)： 31 October 2019 (or earlier) Economic Model The final version of the HYN Economic Model launches in October.
Encrypted project calendar（November 1, 2019）
INS/Insolar: The Insolar (INS) Insolar wallet and the redesigned Insolar Block Explorer will be operational on November 1, 2019. VeChain (VET)：”01 November 2019 BUIDLer Reunion Party BUIDLer Reunion Party in San Francisco from 8–11 PM. uPlexa (UPX)： 01 November 2019 Steadfast Storm — PoS/PoW split (Utility nodes ie. master nodes) — Upcoming Anonymity Network much like TOR — Privacy-based DApps — Reduced network fees. Enjin Coin (ENJ)： 01 November 2019 MFT Binding “ICYMI: On Enjin Coin’s 2nd anniversary (November 1), Enjin MFTs will be bound to hodlers’ blockchain addresses…” Auxilium (AUX)：01 November 2019 AUX Interest Distribution Monthly interest distribution by Auxilium Interest Distribution Platform for coinholders. Also supports charity. Havy (HAVY)：01 November 2019 Token Buyback “Havy tokens buyback, Only in 1 exchange between Idex, Mercatox & Hotbit. The exchange depends on the most lower sell wall.” Egretia (EGT): 01 November 2019 Global DApp Contest SF 2019 Egretia Global DApp Contest in San Francisco.
Encrypted project calendar（November 2, 2019）
Kambria (KAT)： 02 November 2019 VietAI Summit 2019 Kambria joins forces with VietAI for the annual VietAI Summit, with top experts from Google Brain, NVIDIA, Kambria, VietAI, and more!
Encrypted project calendar（November 4, 2019）
Stellar (XLM)： 04 November 2019 Stellar Meridian Conf. Stellar Meridian conference from Nov 4–5 in Mexico City. Cappasity (CAPP)： 04 November 2019 Lisbon Web Summit Lisbon Web Summit in Lisbon, Portugal from November 4–7.
Encrypted project calendar（November 5, 2019）
Nexus (NXS)： 05 November 2019 Tritium Official Release “Remember, Remember the 5th of November, the day Tritium changed Distributed Ledger. Yes, this is an official release date.” NEM (XEM)： 05 November 2019 Innovation Forum — Kyiv NEM Foundation Council Member Anton Bosenko will be speaking in the upcoming International Innovation Forum in Kyiv on November 5, 2019. TomoChain (TOMO): 05 November 2019 TomoX Testnet “Mark your calendar as TomoX testnet will be live on Tuesday, Nov 5th!” aelf (ELF): 05 November 2019 Bug Bounty Program Ends On Oct 24th, 2019 aelf’s biggest bug bounty will launch with a large reward pool. The event will run for almost 2 weeks.
Encrypted project calendar（November 6, 2019）
STEEM/Steem: The Steem (STEEM) SteemFest 4 conference will be held in Bangkok from November 6th to 10th. KIM/Kimcoin: Kimcoin (KIM) Bitfinex will be online at KIM on November 6, 2019 at 12:00 (UTC).
Encrypted project calendar（November 7, 2019）
XRP (XRP)： 07 November 2019 Swell 2019 Ripple hosts Swell from November 7th — 8th in Singapore. BTC/Bitcoin: Malta The A.I. and Blockchain summit will be held in Malta from November 7th to 8th.
Encrypted project calendar（November 8, 2019）
BTC/Bitcoin: The 2nd Global Digital Mining Summit will be held in Frankfurt, Germany from October 8th to 10th. IOTX/IoTeX: IoTex (IOTX) will participate in the CES Expo on November 08
Encrypted project calendar（November 9, 2019）
CENNZ/Centrality: Centrality (CENNZ) will meet in InsurTechNZ Connect — Insurance and Blockchain on October 9th in Auckland. HTMLCOIN (HTML): 09 November 2019 (or earlier) Mandatory Wallet Update Mandatory Wallet Update: there will be a soft fork on our blockchain. This update adds header signature verification on block 997,655.
Encrypted project calendar（November 11, 2019）
PAX/Paxos Standard: Paxos Standard (PAX) 2019 Singapore Financial Technology Festival will be held from November 11th to 15th, and Paxos Standard will attend the conference. Crypto.com Coin (CRO): and 3 others 11 November 2019 Capital Warm-up Party Capital Warm-up Party in Singapore. GoldCoin (GLC): 11 November 2019 Reverse Bitcoin Hardfork The GoldCoin (GLC) Team will be “Reverse Hard Forking” the Bitcoin (BTC) Blockchain…”
Encrypted project calendar（November 12, 2019）
BTC/Bitcoin: The CoinMarketCap Global Conference will be held at the Victoria Theatre in Singapore from November 12th to 13th Binance Coin (BNB) and 7 others: 12 November 2019 CMC Global Conference “The first-ever CoinMarketCap large-scale event: A one-of-a-kind blockchain / crypto experience like you’ve never experienced before.”
Encrypted project calendar（November 13, 2019）
Fetch.ai (FET): 13 November 2019 Cambridge Meetup “Join us for a @Fetch_ai #Cambridge #meetup on 13 November @pantonarms1.” Binance Coin (BNB) and 5 others: 13 November 2019 Blockchain Expo N.A. “It will bring together key industries from across the globe for two days of top-level content and discussion across 5 co-located events…” OKB (OKB): 13 November 2019 Dnipro, Ukraine- Talks Join us in Dnipro as we journey through Ukraine for our OKEx Cryptour on 11 Nov. Centrality (CENNZ): 13 November 2019 AMA Meetup “Ask our CEO @aaronmcdnz anything in person! Join the AMA meetup on 13 November in Singapore.” OKB (OKB): 13 November 2019 OKEx Cryptotour Dnipro “OKEx Cryptour Ukraine 2019 — Dnipro” in Dnipro from 6–9 PM (EET).
Encrypted project calendar（November 14, 2019）
BTC/Bitcoin: The 2019 BlockShow Asia Summit will be held at Marina Bay Sands, Singapore from November 14th to 15th.
Bitcoin (BTC) bulls seem to have decimated the bears. As of the time of writing this article, the leading cryptocurrency is at $9,800 — up over $2,500, some 38%, in the past 36 hours. This is around $800 short of the daily high of $10,600.
Chairman of China’s top leadership announced that China should be expected to take the lead in the global blockchain, so that the exchange rate of Bitcoin against the US dollar rose sharply, and the support level exceeded $10,500.
Review previous articles: https://email@example.com
Bitcoin hashrate has been nosediving over the past few days. As of October 26, Cryptopolitan reported that the Bitcoin network hashrate significantly dropped Meanwhile, the Bitcoin network’s hashrate has been considerably higher than usual, as ... $100 Million Accelerator Fund from Binance Now Supports PARSIQ, a Reverse-Oracle... Nov 3, 2020. Yield ... Bitcoin’s price reached a multi-month high of nearly 9,500 dollars on April 30. There are many speculations about the driving factor behind BTC’s price recovery. However, the reason is clear when it comes to the network’s rising hash rate. The main reason behind the soaring hashrate is that miners are trying to hoard Bitcoins before the ... Binance is looking to consolidate more bitcoin mining hashrate to its pool in Russia and the Central Asia region.. The world’s largest crypto exchange is deploying a physical server node for its ... Our Bitcoin Cash Price Prediction for 2020. BCH, as the rest of the cryptocurrency market, is tied at the hip of bitcoin’s price action. With the latest development in the world and the impending worldwide economic crash, bitcoin failed to decouple itself from traditional markets and lost 40% in one day. The rest of the market slumped in an even harsher fashion, losing 50%+ in one day. Since ... Bitcoin Price Prediction 2022. With the rapid mainstream adoption that bitcoin is experiencing, we can expect that by 2022 the adoption rate of bitcoin will get tripled. Bitcoin doesn’t seem too far off before it replaces fiat in many cases. By 2022, Bitcoin might reach $32,000, given the advancements are stable. Bitcoin Price Prediction 2025 Bitcoin (BTC) Price Prediction – November 1, 2020 After retesting the $14,000 resistance, BTC/USD was compelled to a range-bound movement between $13,600 and $14,000. For the past two days, BTC ... bitcoin wallets created Bitcoin’s supply declines as hashrate remains stable. Meanwhile, just after bitcoin’s major drop in supply due to the halving event, bitcoin’s fundamental network first consolidated and then grew after the capitulation event in March. Briefly, the bitcoin halving slashed miner rewards from 25 bitcoin per day to 12.5 bitcoin per day. Cryptocurrency exchange giant Binance is planning to consolidate its Bitcoin mining hash rate within the Russian and Central Asian regions. BitRiver partnership On Friday, BitRiver and Binance announced that the crypto exchange will deploy a physical server node for the BitRiver pool. It is the largest Bitcoin mining hosting provider in Russia, located in Bratsk. Bitcoin's hashrate has fallen by around 30% since the BTC halving on Monday. CoinMetrics does not anticipate the dip to last long as more efficient miners join the network. The firm reports a new Bitcoin annual issuance rate of just 1.5%. Want to know more?
[index]          
Binance is welcoming LTO Network into its family! Learn more about LTO token and company 👾 https://research.binance.com/projects/lto-network Official website... LIVE Stock Market Today - FED Leaves Rates Unchanged at 25bp [Invest in Stocks] Jun 10, 2020 Blaze Capital 256 watching Live now Gordon Ramsay's perfect burger tutorial GMA - Duration: 9:56. Bitcoin Analysis, Top bitcoin analysis, price prediction, Bitcoin Trading, Bitcoin 2018, Bitcoin Crash, Bitcoin Moon, Bitcoin News, Bitcoin Today, Best Bitcoin Analysis, Bitcoin price, Bitcoin to ... This video is unavailable. Watch Queue Queue. Watch Queue Queue Bitcoin Perspective and why Bitcoin could be $9m by 2025... Forgot to say that DESPITE A 70% CRYPTO CORRECTION: - Global hashrate has doubled since January. - Binance has quadrupled its user base ... 🟡Binance Futures 10% Discount: ... Bitcoin Cash(BCH) hash rate drops 90% after halving. Time to abandon ship? - Duration: 5:52. Cryptocurrency News 2,944 views. 5:52. How to Trade Options on ... #criptovalute #accriptovalute #bitcoin come funziona #btc #altcoin #binance #investire #guadagnare #il bitcoin L'hash rate del BTC ha raggiunto nuovi massimi è un buon segno ? Binance USA per ... 🔵Phemex $112 Extra Bonus: https://phemex.com/web/user/register?group=74&referralCode=I4IEK 🔵Phemex Tutorial Deutsch: https://www.youtube.com/watch?v=hpBOKs-T...