What is Drivechain? A Detailed Beginner's Guide ...

Sidechains: a promising tech that will help cryptocurrencies adapt faster

This is an automatic summary, original reduced by 89%.
A user can "Block" coins in the main chain, and the same amount will appear in the parallel chain.
Transaction TX1, which blocks the money in the main chain to take them out to the alternative; TX2, which realizes the money in altchain and transacts them onwards within this chain; TX3, which blocks the money in altchain to return them back to the main one; TX4, which unlocks the money in the main chain.
What is SPV-PROOF OUT1? It is transaction TX1 and hashes of other transactions in the same block as TX1. So, we can rebuild the hash-tree for all these transactions and check if they really come from the chain 1.
Now, we have a valid input for N coins that came from chain 1 in the TX2. It can be redeemed in chain 2 until the time comes when it should be returned back.
Input TX4.IN in the main chain: "LINK TO THE TX1.OUT + SPV-BLOCK-PROOF + SIGN WITH KEY 'B'". We refer to the TX1.OUT as the main chain has no idea of the alternative one.
The only requirement is to maintain necessary amount of coins in the both chains to fulfill both requests for exchange-to-exchange transactions and for normal withdrawal.
Summary Source | FAQ | Theory | Feedback | Top five keywords: chain#1 transaction#2 coins#3 main#4 Block#5
Post found in /tech, /TechNewsToday, /CryptoCurrency, /BitcoinAll, /bitcoin_uncensored, /Bitcoin, /geek, /technology, /finance and /Futurology.
NOTICE: This thread is for discussing the submission topic only. Do not discuss the concept of the autotldr bot here.
submitted by autotldr to autotldr [link] [comments]

Can someone explain to me in simple and easy to understand terms what the use cases are for the Bitcoin RSK Sidechain and how long do you think it will be before some of these use cases are realized and in use?

submitted by kolinHall to Bitcoin [link] [comments]

12-02 20:23 - 'I support BCH, and I'm fond of the idea of having sidechains and other similar technologies for different usecases (eg. payment streams as explained by AA in that stickied vid; it's a cool idea). I just think that the bulk of sc...' by /u/mtrycz removed from /r/Bitcoin within 15-25min

'''
I support BCH, and I'm fond of the idea of having sidechains and other similar technologies for different usecases (eg. payment streams as explained by AA in that stickied vid; it's a cool idea). I just think that the bulk of scaling should be done on-chain. Why not both?
I don't oppose offchain, and most of BCH folks don't either.
'''
Context Link
Go1dfish undelete link
unreddit undelete link
Author: mtrycz
submitted by removalbot to removalbot [link] [comments]

Sidechain explained to people from the traditional system via analogy: The USD was a Sidechain of Gold between 1944 and 1971 /r/Bitcoin

Sidechain explained to people from the traditional system via analogy: The USD was a Sidechain of Gold between 1944 and 1971 /Bitcoin submitted by BitcoinAllBot to BitcoinAll [link] [comments]

Can someone explain to me if I understand Bitcoin privacy sidechains "threat" correctly?

I am hoping someone can give me some input. A friend of mine has been insisting sidechains will kill off altcoins like Monero. I'm completely open to it. But here's my beef.
Do I understand correctly that if you lock your bitcoin in a sidechain. Lets call it "Drugs/CP/ISIS" sidechain. Basically your bitcoins get locked up there - mixed or exchanged with other coins on the chain. But to move them BACK onto the bitcoin main chain even if all privacy is intact on that side chain so the government has absolutely no way of knowing what happened after Bitcoin address X moved coins to sidechain. And no way of knowing where bitcoins coming off of the sidechain came from.
They know that these particular coins moving OFF of the Drugs/CP/ISIS sidechain are in fact associated with this polluted chain? Why would there be any reason at all for someone who is buying an ounce of weed or using Satoshi dice and trying to avoid a ban by Coinbase to use this sidechain with ring signatures or whatever and paint a target on his back by the FBI? Further - if we assume that bitcoin grows by 10X from where it is now.
What is stopping the government from picking Drugs/CP/ISIS sidechain and telling exchanges they aren't allowed to deal with these polluted coins? Wouldn't this lead to coin tainting where they would be valueless (or worth way less?) ISIS isn't going to want polluted coins & neither is druglord #431?
How is this not even more of a liability than bitcoin on the clear chain from a value perspective? Am I missing something about how this is going to work - I don't understand how you're going to be able to maintain privacy coming off of side chains dedicated to mixing without getting tainted even if they don't know where your coins came from? I mean if bitcoin goes up 10X I fully expect blacklisted coins with wallet integration checkers - and coins getting blacklisted weeks after multiple transactions to become a thing.
I never have or will do anything illegal with crypto and pay all my taxes. I just believe the government has overstepped it's bounds and needs to be put back in place by technology. And I'm trying to peep into the sidechain future.
submitted by rdnkjdi to Monero [link] [comments]

Sidechains: Maaku explains how coins will move from sidechain back to Bitcoins requiring a 3 day transaction loop.

"Conceptually anyone who wants sidecoins and has bitcoins or vice versa can simply move value from one chain to the other, in essence destroying bitcoins and printing sidecoins albeit in a reversible process.
However, this takes a considerable amount of time to clear -- about 3 days -- and blockchain space which requires fees. So in practice we fully expect that someone wanting to trade bitcoins for sidecoins will use a distributed marketplace and atomic cross-chain swaps in order to buy one coin with another, by finding a buyer at the other side.
Use of the pegging mechanism will be limited to market makers who arbitrage when the price starts to deviate from the peg. Make sense?" Source: Maaku Explains BTC restoration with sidechains
submitted by taariqlewis to Bitcoin [link] [comments]

Can someone explain to me in simple and easy to understand terms what the use cases are for the Bitcoin RSK Sidechain and how long do you think it will be before some of these use cases are realized and in use? /r/Bitcoin

Can someone explain to me in simple and easy to understand terms what the use cases are for the Bitcoin RSK Sidechain and how long do you think it will be before some of these use cases are realized and in use? /Bitcoin submitted by ABitcoinAllBot to BitcoinAll [link] [comments]

Sidechains or Drivechains. Can someone explain the difference and how long before we see them implemented? /r/Bitcoin

Sidechains or Drivechains. Can someone explain the difference and how long before we see them implemented? /Bitcoin submitted by BitcoinAllBot to BitcoinAll [link] [comments]

An article explaining how sidechain will impact bitcoins and Altcoins.

An article explaining how sidechain will impact bitcoins and Altcoins. submitted by cuddaloreappu to dogecoin [link] [comments]

Can anyone please explain how sidechains could potentially destroy all altcoins or why they won't? I'm struggling to understand the exact mechanism that connects the sidechain to Bitcoin as well.

With sidechains, how does the sidechain secure itself? Does Bitcoin contribute to its security and how?
submitted by ethbtc to Bitcoin [link] [comments]

“Effectively, [sidechains allow] altcoin development and innovation, without each new chain having its own currency but using bitcoin.” – How to Explain Sidechains to a Parent

“Effectively, [sidechains allow] altcoin development and innovation, without each new chain having its own currency but using bitcoin.” – How to Explain Sidechains to a Parent submitted by bitcoinik to Bitcoin [link] [comments]

How to sell xBricks for money (self post for mod approval)

Preface
I've written this guide with those that are unfamiliar with crypto in mind, however it's still a lengthy process. I'm going to try to present this in a way where you don't have to learn how the underlying crypto technology works, but I will add in links to relevant concepts in case you're curious. This process was a lot more complicated before but I made a web interface to simplify it.
At the time of writing this, FortniteBR BRICKs are worth 10 cents a piece. That makes 1000 bricks worth 100 bucks. The liquidity pool is about $14,000 at the time of writing, meaning that there's room in the market for you to hypothetically get $7,000 if you had a lot of BRICKs.
If at any point throughout this process you need help, DM me!
Misc. Resources That Might Be Helpful
What you need
You will need:
Step 1: Setup
On your desktop computer, install MetaMask. This is an Ethereum Wallet which will allow you to interact with the Ethereum Network and its many sidechains. More on this later.
Follow the setup instructions in MetaMask. If you've never done this before, you'll need to create a new seed phrase. Video tutorial if you get stuck.
YOUR SEED PHRASE IS THE KEY TO YOUR WALLET. ANYONE WHO HAS ACCESS TO YOUR SEED PHRASE CAN TAKE YOUR FUNDS. IF YOU LOSE YOUR SEED PHRASE YOU HAVE NO WAY TO RECOVER YOUR FUNDS. WRITE IT DOWN AND STORE IT IN A SAFE PLACE!!! NEVER GIVE IT OUT TO ANYONE - ANYONE THAT ASKS FOR YOUR SEED PHRASE IS TRYING TO SCAM YOU! DON'T FALL FOR IT!
In the MetaMask interface, you'll see "Main Ethereum Network". This process uses two networks. One of them is the Rinkeby Testnet (where the BRICK tokens are natively) and one of them is the xDAI network which is where we will bridge the tokens to in order to exchange them for Dai, a token which is pegged to the price of the dollar.
From the dropdown, select Rinkeby Testnet. If you're in the assets tab, you should see a thing that shows your ETH balance. Below this, you should see an "add token" button. Click it. Go to "Custom Token" at the top. In "token contract address," paste in the following:
0xe0d8d7b8273de14e628d2f2a4a10f719f898450a
The other fields will autofill. Hit next. You'll now see your BRICK balance (which will be 0, you haven't transferred your bricks yet) in MetaMask if you've done everything right.
You'll need Rinkeby Ether to cover transaction fees. Since we're on a testnet, the Ether is worthless which means people hand it out for free. You can get this Ether from a variety of places:
Now it's time to get your BRICKs from your Reddit vault into your MetaMask wallet.
WARNING: ALL CRYPTO TRANSACTIONS ARE IRREVERSIBLE.
Your Ethereum address shows up under Rinkeby. It should be "0x" followed by a bunch of hex characters. Click on it to copy it to your clipboard. You now need to somehow get this to your mobile device. Email it to yourself, text it to yourself, whatever.
On your Reddit mobile app home screen, click on your profile icon and then go to vault. You'll need to set this up and claim your tokens if you haven't already. Be aware that this is also technically an Ethereum wallet. Keep your seed phrase safe.
Send however many BRICKs you want to sell to your MetaMask wallet. Check to make sure the addresses are the same, but don't worry too much about making a typo or whatever. The chances that you'd make a typo that would result in a valid Ethereum address are slim, if you get a character wrong it'll just tell you it's not a real Ethereum address and prevent you from sending.
It may show an error when you try to send. This is somewhat rare but pretty normal. They often run out of testnet Ether. Come back later and try again.
If it works properly, it'll take about a minute to go through. It may take longer than that.
Once the transaction goes through, you'll see that you have an absurd amount of BRICKs in MetaMask. No, there wasn't a glitch. The people who wrote the code for BRICKs made the decimals of precision weird for some reason. It's off by a factor of 1018. This isn't a big deal.
If you see Bricks and Ether (ETH) in your MetaMask wallet, proceed to the next step. If you're having issues, feel free to DM me.
Step 2: Getting Your BRICKs from Rinkeby to xDai
There's a LOT going on under the hood for this part (deets for those interested). Previously this required manually generating contract interactions, which is kind of a pain if you're new to Ethereum. I made a UI to make this easier (it generates the transactions for you, all you have to do is sign them with your wallet). This took way longer to do than you might guess, so feel free to help a homie out at:
0x4BCcC2569DD93C7dF43431A7b70db569dedB6187
Go to my tool. Hit connect. If you're on the Rinkeby network, it should show your balance in BRICKs. Enter the amount you want to bridge (probably all of them). If neither of us have made any mistakes, it should pop up with a request to spend your BRICKs. If there's any issue with this tool, DM me. This allows the TokenBridge contract to take your BRICKs and put them on the xDai network where you can sell them. This is the part where you'll get an error if you don't have any testnet ETH. Set the gas price to 1 (the suggested price is based on the Main Ethereum Network - it's way too high). After you approve that, it'll give you another thing to accept. This is the actual transaction where it'll bridge to xDai. Again, make sure the gas price is set to 1 and confirm the transaction.
Add xDai to MetaMask
Switch to the xDai network. We're going to add another token. Again, go to "add token" > "custom token" > "token contract address". Paste in:
0x2f9ceBf5De3bc25E0643D0E66134E5bf5c48e191
If the transactions have gone through, you should see your xBricks (the name for BRICKs that have been bridged to xDai) in MetaMask. If not, wait a bit for the transactions to go through. Sometimes there are slowdowns that cause bridging to take a while. Shouldn't take too long, though. Once that's done, you're ready for the next step.
Step 3: Trading Your xBricks for xDai
Go to Honeyswap. Hit "select a token." You'll need to paste in the xBrick address again. Here it is:
0x2f9ceBf5De3bc25E0643D0E66134E5bf5c48e191
Click xBrick.
You'll need to flipflop the trade around by hitting the arrow button. xBrick should be on top. Type in the amount of xBricks you want to sell, or hit max to sell all of them. 1 xDai = $1. You'll need to hit approve first. Set gas price to 1 again. Then you can complete the trade by hitting swap. After a bit, the xDai should show up in your wallet.
Step 4: Mainnet
Everything on Mainnet costs actual money to do. It costs about 50 cents to make a transaction and it costs about 3 bucks to use an exchange like the one we just used. If you don't have mainnet Ether, you won't be able to do anything with your mainnet Dai (what xDai is called when it's bridged back to the main Ethereum network). You may be able to find someone to lend you some ETH to make these transactions with. Whatever you do, just be aware.
If you still want to bridge your xDai into Dai, go here and make sure xDai is on the left. If it's not, go in the top right and select xDai chain. Enter the amount of xDai you want to bridge to mainnet and then hit transfer. Follow the prompts. This part may take up to an hour due to recent network congestion. After it's done, if you go back to Main Ethereum Network in MetaMask you should see your Dai.
If you have a few bucks of ETH, you can use UniSwap to convert your Dai to even more ETH. Uniswap tutorial
Things you can do with ETH
submitted by Oninteressant123 to u/Oninteressant123 [link] [comments]

Scaling Reddit Community Points with Arbitrum Rollup: a piece of cake

Scaling Reddit Community Points with Arbitrum Rollup: a piece of cake
https://preview.redd.it/b80c05tnb9e51.jpg?width=2550&format=pjpg&auto=webp&s=850282c1a3962466ed44f73886dae1c8872d0f31
Submitted for consideration to The Great Reddit Scaling Bake-Off
Baked by the pastry chefs at Offchain Labs
Please send questions or comments to [[email protected] ](mailto:[email protected])
1. Overview
We're excited to submit Arbitrum Rollup for consideration to The Great Reddit Scaling Bake-Off. Arbitrum Rollup is the only Ethereum scaling solution that supports arbitrary smart contracts without compromising on Ethereum's security or adding points of centralization. For Reddit, this means that Arbitrum can not only scale the minting and transfer of Community Points, but it can foster a creative ecosystem built around Reddit Community Points enabling points to be used in a wide variety of third party applications. That's right -- you can have your cake and eat it too!
Arbitrum Rollup isn't just Ethereum-style. Its Layer 2 transactions are byte-for-byte identical to Ethereum, which means Ethereum users can continue to use their existing addresses and wallets, and Ethereum developers can continue to use their favorite toolchains and development environments out-of-the-box with Arbitrum. Coupling Arbitrum’s tooling-compatibility with its trustless asset interoperability, Reddit not only can scale but can onboard the entire Ethereum community at no cost by giving them the same experience they already know and love (well, certainly know).
To benchmark how Arbitrum can scale Reddit Community Points, we launched the Reddit contracts on an Arbitrum Rollup chain. Since Arbitrum provides full Solidity support, we didn't have to rewrite the Reddit contracts or try to mimic their functionality using an unfamiliar paradigm. Nope, none of that. We launched the Reddit contracts unmodified on Arbitrum Rollup complete with support for minting and distributing points. Like every Arbitrum Rollup chain, the chain included a bridge interface in which users can transfer Community Points or any other asset between the L1 and L2 chains. Arbitrum Rollup chains also support dynamic contract loading, which would allow third-party developers to launch custom ecosystem apps that integrate with Community Points on the very same chain that runs the Reddit contracts.
1.1 Why Ethereum
Perhaps the most exciting benefit of distributing Community Points using a blockchain is the ability to seamlessly port points to other applications and use them in a wide variety of contexts. Applications may include simple transfers such as a restaurant that allows Redditors to spend points on drinks. Or it may include complex smart contracts -- such as placing Community Points as a wager for a multiparty game or as collateral in a financial contract.
The common denominator between all of the fun uses of Reddit points is that it needs a thriving ecosystem of both users and developers, and the Ethereum blockchain is perhaps the only smart contract platform with significant adoption today. While many Layer 1 blockchains boast lower cost or higher throughput than the Ethereum blockchain, more often than not, these attributes mask the reality of little usage, weaker security, or both.
Perhaps another platform with significant usage will rise in the future. But today, Ethereum captures the mindshare of the blockchain community, and for Community Points to provide the most utility, the Ethereum blockchain is the natural choice.
1.2 Why Arbitrum
While Ethereum's ecosystem is unmatched, the reality is that fees are high and capacity is too low to support the scale of Reddit Community Points. Enter Arbitrum. Arbitrum Rollup provides all of the ecosystem benefits of Ethereum, but with orders of magnitude more capacity and at a fraction of the cost of native Ethereum smart contracts. And most of all, we don't change the experience from users. They continue to use the same wallets, addresses, languages, and tools.
Arbitrum Rollup is not the only solution that can scale payments, but it is the only developed solution that can scale both payments and arbitrary smart contracts trustlessly, which means that third party users can build highly scalable add-on apps that can be used without withdrawing money from the Rollup chain. If you believe that Reddit users will want to use their Community Points in smart contracts--and we believe they will--then it makes the most sense to choose a single scaling solution that can support the entire ecosystem, eliminating friction for users.
We view being able to run smart contracts in the same scaling solution as fundamentally critical since if there's significant demand in running smart contracts from Reddit's ecosystem, this would be a load on Ethereum and would itself require a scaling solution. Moreover, having different scaling solutions for the minting/distribution/spending of points and for third party apps would be burdensome for users as they'd have to constantly shuffle their Points back and forth.
2. Arbitrum at a glance
Arbitrum Rollup has a unique value proposition as it offers a combination of features that no other scaling solution achieves. Here we highlight its core attributes.
Decentralized. Arbitrum Rollup is as decentralized as Ethereum. Unlike some other Layer 2 scaling projects, Arbitrum Rollup doesn't have any centralized components or centralized operators who can censor users or delay transactions. Even in non-custodial systems, centralized components provide a risk as the operators are generally incentivized to increase their profit by extracting rent from users often in ways that severely degrade user experience. Even if centralized operators are altruistic, centralized components are subject to hacking, coercion, and potential liability.
Massive Scaling. Arbitrum achieves order of magnitude scaling over Ethereum's L1 smart contracts. Our software currently supports 453 transactions-per-second for basic transactions (at 1616 Ethereum gas per tx). We have a lot of room left to optimize (e.g. aggregating signatures), and over the next several months capacity will increase significantly. As described in detail below, Arbitrum can easily support and surpass Reddit's anticipated initial load, and its capacity will continue to improve as Reddit's capacity needs grow.
Low cost. The cost of running Arbitrum Rollup is quite low compared to L1 Ethereum and other scaling solutions such as those based on zero-knowledge proofs. Layer 2 fees are low, fixed, and predictable and should not be overly burdensome for Reddit to cover. Nobody needs to use special equipment or high-end machines. Arbitrum requires validators, which is a permissionless role that can be run on any reasonable on-line machine. Although anybody can act as a validator, in order to protect against a “tragedy of the commons” and make sure reputable validators are participating, we support a notion of “invited validators” that are compensated for their costs. In general, users pay (low) fees to cover the invited validators’ costs, but we imagine that Reddit may cover this cost for its users. See more on the costs and validator options below.
Ethereum Developer Experience. Not only does Arbitrum support EVM smart contracts, but the developer experience is identical to that of L1 Ethereum contracts and fully compatible with Ethereum tooling. Developers can port existing Solidity apps or write new ones using their favorite and familiar toolchains (e.g. Truffle, Buidler). There are no new languages or coding paradigms to learn.
Ethereum wallet compatibility. Just as in Ethereum, Arbitrum users need only hold keys, but do not have to store any coin history or additional data to protect or access their funds. Since Arbitrum transactions are semantically identical to Ethereum L1 transactions, existing Ethereum users can use their existing Ethereum keys with their existing wallet software such as Metamask.
Token interoperability. Users can easily transfer their ETH, ERC-20 and ERC-721 tokens between Ethereum and the Arbitrum Rollup chain. As we explain in detail below, it is possible to mint tokens in L2 that can subsequently be withdrawn and recognized by the L1 token contract.
Fast finality. Transactions complete with the same finality time as Ethereum L1 (and it's possible to get faster finality guarantees by trading away trust assumptions; see the Arbitrum Rollup whitepaper for details).
Non-custodial. Arbitrum Rollup is a non-custodial scaling solution, so users control their funds/points and neither Reddit nor anyone else can ever access or revoke points held by users.
Censorship Resistant. Since it's completely decentralized, and the Arbitrum protocol guarantees progress trustlessly, Arbitrum Rollup is just as censorship-proof as Ethereum.
Block explorer. The Arbitrum Rollup block explorer allows users to view and analyze transactions on the Rollup chain.
Limitations
Although this is a bake-off, we're not going to sugar coat anything. Arbitrum Rollup, like any Optimistic Rollup protocol, does have one limitation, and that's the delay on withdrawals.
As for the concrete length of the delay, we've done a good deal of internal modeling and have blogged about this as well. Our current modeling suggests a 3-hour delay is sufficient (but as discussed in the linked post there is a tradeoff space between the length of the challenge period and the size of the validators’ deposit).
Note that this doesn't mean that the chain is delayed for three hours. Arbitrum Rollup supports pipelining of execution, which means that validators can keep building new states even while previous ones are “in the pipeline” for confirmation. As the challenge delays expire for each update, a new state will be confirmed (read more about this here).
So activity and progress on the chain are not delayed by the challenge period. The only thing that's delayed is the consummation of withdrawals. Recall though that any single honest validator knows immediately (at the speed of L1 finality) which state updates are correct and can guarantee that they will eventually be confirmed, so once a valid withdrawal has been requested on-chain, every honest party knows that the withdrawal will definitely happen. There's a natural place here for a liquidity market in which a validator (or someone who trusts a validator) can provide withdrawal loans for a small interest fee. This is a no-risk business for them as they know which withdrawals will be confirmed (and can force their confirmation trustlessly no matter what anyone else does) but are just waiting for on-chain finality.
3. The recipe: How Arbitrum Rollup works
For a description of the technical components of Arbitrum Rollup and how they interact to create a highly scalable protocol with a developer experience that is identical to Ethereum, please refer to the following documents:
Arbitrum Rollup Whitepaper
Arbitrum academic paper (describes a previous version of Arbitrum)
4. Developer docs and APIs
For full details about how to set up and interact with an Arbitrum Rollup chain or validator, please refer to our developer docs, which can be found at https://developer.offchainlabs.com/.
Note that the Arbitrum version described on that site is older and will soon be replaced by the version we are entering in Reddit Bake-Off, which is still undergoing internal testing before public release.
5. Who are the validators?
As with any Layer 2 protocol, advancing the protocol correctly requires at least one validator (sometimes called block producers) that is honest and available. A natural question is: who are the validators?
Recall that the validator set for an Arbitrum chain is open and permissionless; anyone can start or stop validating at will. (A useful analogy is to full nodes on an L1 chain.) But we understand that even though anyone can participate, Reddit may want to guarantee that highly reputable nodes are validating their chain. Reddit may choose to validate the chain themselves and/or hire third-party validators.To this end, we have begun building a marketplace for validator-for-hire services so that dapp developers can outsource validation services to reputable nodes with high up-time. We've announced a partnership in which Chainlink nodes will provide Arbitrum validation services, and we expect to announce more partnerships shortly with other blockchain infrastructure providers.
Although there is no requirement that validators are paid, Arbitrum’s economic model tracks validators’ costs (e.g. amount of computation and storage) and can charge small fees on user transactions, using a gas-type system, to cover those costs. Alternatively, a single party such as Reddit can agree to cover the costs of invited validators.
6. Reddit Contract Support
Since Arbitrum contracts and transactions are byte-for-byte compatible with Ethereum, supporting the Reddit contracts is as simple as launching them on an Arbitrum chain.
Minting. Arbitrum Rollup supports hybrid L1/L2 tokens which can be minted in L2 and then withdrawn onto the L1. An L1 contract at address A can make a special call to the EthBridge which deploys a "buddy contract" to the same address A on an Arbitrum chain. Since it's deployed at the same address, users can know that the L2 contract is the authorized "buddy" of the L1 contract on the Arbitrum chain.
For minting, the L1 contract is a standard ERC-20 contract which mints and burns tokens when requested by the L2 contract. It is paired with an ERC-20 contract in L2 which mints tokens based on whatever programmer provided minting facility is desired and burns tokens when they are withdrawn from the rollup chain. Given this base infrastructure, Arbitrum can support any smart contract based method for minting tokens in L2, and indeed we directly support Reddit's signature/claim based minting in L2.
Batch minting. What's better than a mint cookie? A whole batch! In addition to supporting Reddit’s current minting/claiming scheme, we built a second minting design, which we believe outperforms the signature/claim system in many scenarios.
In the current system, Reddit periodically issues signed statements to users, who then take those statements to the blockchain to claim their tokens. An alternative approach would have Reddit directly submit the list of users/amounts to the blockchain and distribute the tokens to the users without the signature/claim process.
To optimize the cost efficiency of this approach, we designed an application-specific compression scheme to minimize the size of the batch distribution list. We analyzed the data from Reddit's previous distributions and found that the data is highly compressible since token amounts are small and repeated, and addresses appear multiple times. Our function groups transactions by size, and replaces previously-seen addresses with a shorter index value. We wrote client code to compress the data, wrote a Solidity decompressing function, and integrated that function into Reddit’s contract running on Arbitrum.
When we ran the compression function on the previous Reddit distribution data, we found that we could compress batched minting data down to to 11.8 bytes per minting event (averaged over a 6-month trace of Reddit’s historical token grants)compared with roughly 174 bytes of on-chain data needed for the signature claim approach to minting (roughly 43 for an RLP-encoded null transaction + 65 for Reddit's signature + 65 for the user's signature + roughly 8 for the number of Points) .
The relative benefit of the two approaches with respect to on-chain call data cost depends on the percentage of users that will actually claim their tokens on chain. With the above figures, batch minting will be cheaper if roughly 5% of users redeem their claims. We stress that our compression scheme is not Arbitrum-specific and would be beneficial in any general-purpose smart contract platform.
8. Benchmarks and costs
In this section, we give the full costs of operating the Reddit contracts on an Arbitrum Rollup chain including the L1 gas costs for the Rollup chain, the costs of computation and storage for the L2 validators as well as the capital lockup requirements for staking.
Arbitrum Rollup is still on testnet, so we did not run mainnet benchmarks. Instead, we measured the L1 gas cost and L2 workload for Reddit operations on Arbitrum and calculated the total cost assuming current Ethereum gas prices. As noted below in detail, our measurements do not assume that Arbitrum is consuming the entire capacity of Ethereum. We will present the details of our model now, but for full transparency you can also play around with it yourself and adjust the parameters, by copying the spreadsheet found here.
Our cost model is based on measurements of Reddit’s contracts, running unmodified (except for the addition of a batch minting function) on Arbitrum Rollup on top of Ethereum.
On the distribution of transactions and frequency of assertions. Reddit's instructions specify the following minimum parameters that submissions should support:
Over a 5 day period, your scaling PoC should be able to handle:
  • 100,000 point claims (minting & distributing points)
  • 25,000 subscriptions
  • 75,000 one-off points burning
  • 100,000 transfers
We provide the full costs of operating an Arbitrum Rollup chain with this usage under the assumption that tokens are minted or granted to users in batches, but other transactions are uniformly distributed over the 5 day period. Unlike some other submissions, we do not make unrealistic assumptions that all operations can be submitted in enormous batches. We assume that batch minting is done in batches that use only a few percent on an L1 block’s gas, and that other operations come in evenly over time and are submitted in batches, with one batch every five minutes to keep latency reasonable. (Users are probably already waiting for L1 finality, which takes at least that long to achieve.)
We note that assuming that there are only 300,000 transactions that arrive uniformly over the 5 day period will make our benchmark numbers lower, but we believe that this will reflect the true cost of running the system. To see why, say that batches are submitted every five minutes (20 L1 blocks) and there's a fixed overhead of c bytes of calldata per batch, the cost of which will get amortized over all transactions executed in that batch. Assume that each individual transaction adds a marginal cost of t. Lastly assume the capacity of the scaling system is high enough that it can support all of Reddit's 300,000 transactions within a single 20-block batch (i.e. that there is more than c + 300,000*t byes of calldata available in 20 blocks).
Consider what happens if c, the per-batch overhead, is large (which it is in some systems, but not in Arbitrum). In the scenario that transactions actually arrive at the system's capacity and each batch is full, then c gets amortized over 300,000 transactions. But if we assume that the system is not running at capacity--and only receives 300,000 transactions arriving uniformly over 5 days-- then each 20-block assertion will contain about 200 transactions, and thus each transaction will pay a nontrivial cost due to c.
We are aware that other proposals presented scaling numbers assuming that 300,000 transactions arrived at maximum capacity and was executed in a single mega-transaction, but according to our estimates, for at least one such report, this led to a reported gas price that was 2-3 orders of magnitude lower than it would have been assuming uniform arrival. We make more realistic batching assumptions, and we believe Arbitrum compares well when batch sizes are realistic.
Our model. Our cost model includes several sources of cost:
  • L1 gas costs: This is the cost of posting transactions as calldata on the L1 chain, as well as the overhead associated with each batch of transactions, and the L1 cost of settling transactions in the Arbitrum protocol.
  • Validator’s staking costs: In normal operation, one validator will need to be staked. The stake is assumed to be 0.2% of the total value of the chain (which is assumed to be $1 per user who is eligible to claim points). The cost of staking is the interest that could be earned on the money if it were not staked.
  • Validator computation and storage: Every validator must do computation to track the chain’s processing of transactions, and must maintain storage to keep track of the contracts’ EVM storage. The cost of computation and storage are estimated based on measurements, with the dollar cost of resources based on Amazon Web Services pricing.
It’s clear from our modeling that the predominant cost is for L1 calldata. This will probably be true for any plausible rollup-based system.
Our model also shows that Arbitrum can scale to workloads much larger than Reddit’s nominal workload, without exhausting L1 or L2 resources. The scaling bottleneck will ultimately be calldata on the L1 chain. We believe that cost could be reduced substantially if necessary by clever encoding of data. (In our design any compression / decompression of L2 transaction calldata would be done by client software and L2 programs, never by an L1 contract.)
9. Status of Arbitrum Rollup
Arbitrum Rollup is live on Ethereum testnet. All of the code written to date including everything included in the Reddit demo is open source and permissively licensed under the Apache V2 license. The first testnet version of Arbitrum Rollup was released on testnet in February. Our current internal version, which we used to benchmark the Reddit contracts, will be released soon and will be a major upgrade.
Both the Arbitrum design as well as the implementation are heavily audited by independent third parties. The Arbitrum academic paper was published at USENIX Security, a top-tier peer-reviewed academic venue. For the Arbitrum software, we have engaged Trail of Bits for a security audit, which is currently ongoing, and we are committed to have a clean report before launching on Ethereum mainnet.
10. Reddit Universe Arbitrum Rollup Chain
The benchmarks described in this document were all measured using the latest internal build of our software. When we release the new software upgrade publicly we will launch a Reddit Universe Arbitrum Rollup chain as a public demo, which will contain the Reddit contracts as well as a Uniswap instance and a Connext Hub, demonstrating how Community Points can be integrated into third party apps. We will also allow members of the public to dynamically launch ecosystem contracts. We at Offchain Labs will cover the validating costs for the Reddit Universe public demo.
If the folks at Reddit would like to evaluate our software prior to our public demo, please email us at [email protected] and we'd be more than happy to provide early access.
11. Even more scaling: Arbitrum Sidechains
Rollups are an excellent approach to scaling, and we are excited about Arbitrum Rollup which far surpasses Reddit's scaling needs. But looking forward to Reddit's eventual goal of supporting hundreds of millions of users, there will likely come a time when Reddit needs more scaling than any Rollup protocol can provide.
While Rollups greatly reduce costs, they don't break the linear barrier. That is, all transactions have an on-chain footprint (because all calldata must be posted on-chain), albeit a far smaller one than on native Ethereum, and the L1 limitations end up being the bottleneck for capacity and cost. Since Ethereum has limited capacity, this linear use of on-chain resources means that costs will eventually increase superlinearly with traffic.
The good news is that we at Offchain Labs have a solution in our roadmap that can satisfy this extreme-scaling setting as well: Arbitrum AnyTrust Sidechains. Arbitrum Sidechains are similar to Arbitrum Rollup, but deviate in that they name a permissioned set of validators. When a chain’s validators agree off-chain, they can greatly reduce the on-chain footprint of the protocol and require almost no data to be put on-chain. When validators can't reach unanimous agreement off-chain, the protocol reverts to Arbitrum Rollup. Technically, Arbitrum Sidechains can be viewed as a hybrid between state channels and Rollup, switching back and forth as necessary, and combining the performance and cost that state channels can achieve in the optimistic case, with the robustness of Rollup in other cases. The core technical challenge is how to switch seamlessly between modes and how to guarantee that security is maintained throughout.
Arbitrum Sidechains break through this linear barrier, while still maintaining a high level of security and decentralization. Arbitrum Sidechains provide the AnyTrust guarantee, which says that as long as any one validator is honest and available (even if you don't know which one will be), the L2 chain is guaranteed to execute correctly according to its code and guaranteed to make progress. Unlike in a state channel, offchain progress does not require unanimous consent, and liveness is preserved as long as there is a single honest validator.
Note that the trust model for Arbitrum Sidechains is much stronger than for typical BFT-style chains which introduce a consensus "voting" protocols among a small permissioned group of validators. BFT-based protocols require a supermajority (more than 2/3) of validators to agree. In Arbitrum Sidechains, by contrast, all you need is a single honest validator to achieve guaranteed correctness and progress. Notice that in Arbitrum adding validators strictly increases security since the AnyTrust guarantee provides correctness as long as any one validator is honest and available. By contrast, in BFT-style protocols, adding nodes can be dangerous as a coalition of dishonest nodes can break the protocol.
Like Arbitrum Rollup, the developer and user experiences for Arbitrum Sidechains will be identical to that of Ethereum. Reddit would be able to choose a large and diverse set of validators, and all that they would need to guarantee to break through the scaling barrier is that a single one of them will remain honest.
We hope to have Arbitrum Sidechains in production in early 2021, and thus when Reddit reaches the scale that surpasses the capacity of Rollups, Arbitrum Sidechains will be waiting and ready to help.
While the idea to switch between channels and Rollup to get the best of both worlds is conceptually simple, getting the details right and making sure that the switch does not introduce any attack vectors is highly non-trivial and has been the subject of years of our research (indeed, we were working on this design for years before the term Rollup was even coined).
12. How Arbitrum compares
We include a comparison to several other categories as well as specific projects when appropriate. and explain why we believe that Arbitrum is best suited for Reddit's purposes. We focus our attention on other Ethereum projects.
Payment only Rollups. Compared to Arbitrum Rollup, ZK-Rollups and other Rollups that only support token transfers have several disadvantages:
  • As outlined throughout the proposal, we believe that the entire draw of Ethereum is in its rich smart contracts support which is simply not achievable with today's zero-knowledge proof technology. Indeed, scaling with a ZK-Rollup will add friction to the deployment of smart contracts that interact with Community Points as users will have to withdraw their coins from the ZK-Rollup and transfer them to a smart contract system (like Arbitrum). The community will be best served if Reddit builds on a platform that has built-in, frictionless smart-contract support.
  • All other Rollup protocols of which we are aware employ a centralized operator. While it's true that users retain custody of their coins, the centralized operator can often profit from censoring, reordering, or delaying transactions. A common misconception is that since they're non-custodial protocols, a centralized sequencer does not pose a risk but this is incorrect as the sequencer can wreak havoc or shake down users for side payments without directly stealing funds.
  • Sidechain type protocols can eliminate some of these issues, but they are not trustless. Instead, they require trust in some quorum of a committee, often requiring two-third of the committee to be honest, compared to rollup protocols like Arbitrum that require only a single honest party. In addition, not all sidechain type protocols have committees that are diverse, or even non-centralized, in practice.
  • Plasma-style protocols have a centralized operator and do not support general smart contracts.
13. Concluding Remarks
While it's ultimately up to the judges’ palate, we believe that Arbitrum Rollup is the bakeoff choice that Reddit kneads. We far surpass Reddit's specified workload requirement at present, have much room to optimize Arbitrum Rollup in the near term, and have a clear path to get Reddit to hundreds of millions of users. Furthermore, we are the only project that gives developers and users the identical interface as the Ethereum blockchain and is fully interoperable and tooling-compatible, and we do this all without any new trust assumptions or centralized components.
But no matter how the cookie crumbles, we're glad to have participated in this bake-off and we thank you for your consideration.
About Offchain Labs
Offchain Labs, Inc. is a venture-funded New York company that spun out of Princeton University research, and is building the Arbitrum platform to usher in the next generation of scalable, interoperable, and compatible smart contracts. Offchain Labs is backed by Pantera Capital, Compound VC, Coinbase Ventures, and others.
Leadership Team
Ed Felten
Ed Felten is Co-founder and Chief Scientist at Offchain Labs. He is on leave from Princeton University, where he is the Robert E. Kahn Professor of Computer Science and Public Affairs. From 2015 to 2017 he served at the White House as Deputy United States Chief Technology Officer and senior advisor to the President. He is an ACM Fellow and member of the National Academy of Engineering. Outside of work, he is an avid runner, cook, and L.A. Dodgers fan.
Steven Goldfeder
Steven Goldfeder is Co-founder and Chief Executive Officer at Offchain Labs. He holds a PhD from Princeton University, where he worked at the intersection of cryptography and cryptocurrencies including threshold cryptography, zero-knowledge proof systems, and post-quantum signatures. He is a co-author of Bitcoin and Cryptocurrency Technologies, the leading textbook on cryptocurrencies, and he has previously worked at Google and Microsoft Research, where he co-invented the Picnic signature algorithm. When not working, you can find Steven spending time with his family, taking a nature walk, or twisting balloons.
Harry Kalodner
Harry Kalodner is Co-founder and Chief Technology Officer at Offchain Labs where he leads the engineering team. Before the company he attended Princeton as a Ph.D candidate where his research explored economics, anonymity, and incentive compatibility of cryptocurrencies, and he also has worked at Apple. When not up at 3:00am writing code, Harry occasionally sleeps.
submitted by hkalodner to ethereum [link] [comments]

When Avalanche on Tezos? (scaling at layer 1)

In May 2018, Team Rocket layed out their revolutionary white paper on how to create a high scalability blockchain 3K TPS at layer 1 while remaining highly decentralized (2000+ nodes) without sidechains, sub 1 second finality, no transaction fees/gas with metastability (much more resiliant than 51% attack vector). Lots of amazing inovation here.
In Oct of 2018, we had Tezos Dev Edward Tate of Nomadic Labs start an implementation to ammend the Tezos protocol to implement Avalanche so we could in theory have a massively scalable, decentralized and super fast finality blockchain - something we are lacking still today. This project was funded by the Foundation. The name of the project was Igloo, but looking at the gitlab repository, it looks like work halted on it 1 year ago. Edward Tate has moved on working on other stuff.
Fast forward to today, and we now have Emin Gun Sirer is now launching his own blockchain "Avalanche". Emin, btw was a Tezos ICO advisor who was post-Tezos launch doing research at Cornell University to scale Tezos, but is now doing his own blockchain & targetting the same sector as Tezos originally was focusing on: Revolutionizing the financial sector.
Meanwhile Tezos still has no signicant scalability implemented despite murbard thinking we could 100x TPS 1 year ago without even making many major changes. Ethereum 2.0 is going down the sharding route, which Emin claimed will result in many head aches because of latency and other more complex state related issues.
Questions:
  1. What do the core dev Tezos really think of Avalanche? Especially now that Avalanche testnet has proven itself with 5K TPS w/1000 nodes and sub 1 second finality?
  2. What about murbard? I know you stated there's lower hanging fruit, but I don't recall your comments on the Avalanche protocol before. Considering you follow core and consensus protocols pretty closely and know Emin personally, you must have an opinion. Care to comment? :-)
  3. Why did Igloo/Ed Tate stop work on it 1 year ago?
  4. Are there any plans to upgrade Tezos to an Avalanche scaling solution? If so, what's the progress/time-line on this?
  5. Avalanche is a DAG w/UTXO structure. Tezos is dPoS with "Account Model" (a la ETH), so no UTXO. Even if Tezos wanted to upgrade its layer 1 to implement the Avalanche protocol, it sounds to me like this would be a massive software development under taking, right? I mean, we'd be stripping out core parts of Tezos, like switching a Diesel engine on a car for a lithium battery Tesla engine, while the car is being driven. On top of that it'd have to be done in OCaml, which is not at all trivial. Is this really feasable within a reasonable amount of time, like how long are we talking about if we really wanted to do this?
  6. What are the latest thoughts on how to scale Tezos at Layer 1? I know Tezos is working on Plasma at Layer 2 and TenderBake, but as Emin puts it, that's an old classical consensus model and suffers from various trade offs, as does the Nakamoto (Bitcoin's) consensus algo. The Avalanche team published this simple consensus protocol comparison matrix. Emin claims Avalanche is the best of both worlds. Ethereum meanwhile is working in 6 different scaling directions at once, but NONE of them have all to the advantages of the Avalanche Protocol see: ETH scaling matrix comparison, but clearly scaling matters and it's arguably the most complex thing to implement on blockchains while retaining high decentralization. So what are the Tezos' scaling plans in the works or being seriously considered for implementation?
Thanks in advance!
EDIT: Thanks for the gold, it's not necessary, but thank you.
submitted by drhex2c to tezos [link] [comments]

Weekly Wrap: This Week In Chainlink August 31 - September 6

Weekly Wrap: This Week In Chainlink August 31 - September 6

Chainlink Hackathon - September 7th - 27th!

We've already received over 300 developer signups from over 40 countries for the Chainlink Hackathon. Get ready to join one of the biggest blockchain developer events of the year and build the next top DeFi dApp with support from our world-class mentors and a chance to win over $40K prizes.

Announcements and Integrations 🎉

@synthetix_io is now fully #PoweredByChainlink, switching all its cryptocurrency and index synths to Chainlink's Price Reference Data due to its high-quality data, decentralization, & ability to scale the platform to secure more value.

Bitcoin smart contract platform @RSKsmart has successfully integrated Chainlink oracles via its @rif_os technology. This allows RSK developers to build smart contract applications connected to real-world data that are secured by the Bitcoin blockchain.

@01node is a new node operator supporting Chainlink's live Price Reference Contracts. As operators experienced in securing millions of USD for PoS chains, they bring added decentralization by running their own physical servers that further minimize cloud dependencies.

Decentralized lending protocol @useteller is live on testnet consuming Chainlink's Price Reference Data for ETH/USD, BTC/USD & LINK/USD. These price feeds help Teller ensure that all APR calculations for unsecured loans reflect real market conditions.

Telecommunications blockchain @QLCchain is integrating Chainlink to make its aggregated data available to smart contracts. This data can power new DeFi applications like automating payments between telco providers, tokenizing telco infrastructure & more.

Social reputation score provider @DecentrNet is integrating Chainlink to allow users to share their data in #DeFi dApps to obtain better interest & collateralization rates. Chainlink also helps Decentr make this key data available across any blockchain.

@opium_network is using Chainlink's USDT/USD Price Reference Data live on mainnet to launch the first credit default swap on a centralized stablecoin—USDT. This is another example of how Chainlink oracles are powering innovative DeFi products.

Blockchain card game @EtherLegends will use Chainlink VRF to power their random distribution of NFT-backed end-of-season rewards. These rare items will be awarded to top players at the end of the ongoing season with verifiable proof of fair distribution.

We’re thrilled to award a grant to @ensdomains from the Chainlink Community Grant Program: https://blog.chain.link/introducing-the-chainlink-community-grant-program/…, supporting them in developing human-readable names for oracle contracts, making Chainlink easily accessible to even more smart contract devs

Featured Videos & Educational Pieces 🎥

DeFi is disrupting finance and crypto by moving beyond tokens and wallets into sophisticated smart contract applications that allow p2p lending, liquidity mining, synthetic assets, derivatives, and more. DeFi pioneers Sergey Nazarov (Chainlink), Andre Cronje (yEarn), Stani Kulechoiv (Aave), and Kain Warwick (Synthetix) come together to explain DeFi’s remarkable growth on Ethereum, expansion into new markets, and the impact of live infrastructure, especially decentralized oracles, on DeFi protocols.

Chainlink Labs Chief Scientist Dr. Ari Jules gives a #SmartCon Keynote explaining how DECO helps Chainlink oracles liberate more web data for smart contracts, including identity records, financial data, accredited investor confirmation, supply chain logistics, and more. Using DECO to make this data available on-chain allows blockchains to enhance many enterprise use cases today while still retaining the key property of data confidentiality.

Chainlink-powered decentralized oracles provide smart contracts with definitive truth about the validity of real-world data. In this Keynote, Sergey Nazarov explains how Chainlink is using its secure and reliable oracles to expand the addressable market of smart contract applications into the trillions, thanks to opening up blockchain applications in DeFi, CeFi, Fintech, Web 2.0, and enterprise systems. He also discusses Chainlink’s new DECO acquisition and how it opens up access to web data for smart contracts while preserving data security and confidentiality.

Other SmartCon talks now posted include:

Ecosystem & Community Celebrations 👏


Upcoming Events 📅


Are you interested in hosting your own meetup? Apply to become a Chainlink Community Advocate today: https://events.chain.link/advocate

Chainlink Labs is hiring to build Chainlink’s network: Check out these open roles 👩‍💼

View all open roles at https://careers.smartcontract.com
Are there other community content and celebrations that we missed? Post them in the comments below! ⤵️
submitted by linkedkeenan to Chainlink [link] [comments]

Defi Coins List In Detail

A Detail List Of Defi Coin

Lending

Trading

Payments

Wallets

Interfaces

Infrastructure

Analytics

Education

Podcasts

Newsletters

Communities

submitted by jakkkmotivator to Latest_Defi_News [link] [comments]

RiB Newsletter #15 – Turbofish in the Blocksea

Rust blockchain development continued at its typical blistering pace, and again it's impossible to follow everything going on.
This month we see continued advancement in zero-knowledge computing, an obvious focus from the entire blockchain industry on the DeFi phenomenon, and some new hackathons with opportunities for Rust developers.
Every month seems to bring advancements in zero-knowledge proofs, and new implementations in Rust. It is a research area that will probably impact the general computing industry eventually, and one where the blockchain industry is leading the way, and one where Rust has a huge foothold. Even projects that are not written in Rust we see implementing their zero-knowledge cryptography in Rust. But this stuff is extremely technical, and improving at a rapid pace. We fear we will never understand it.
There are several Rust blockchains now in development that are built around zero-knowledge VMs, whose smart contracts create zero-knowledge proofs:
These are networks that support nearly arbitrary computation over secret inputs. Like programable Zcash.
Speaking of Zcash, the zkSNARK pioneers announced their next-generation zero-knowledge proof system, called Halo 2, which uses a new zkSNARK construction, PLONK.
Two projects built on Rust blockchains launched this month: Serum, a decentralized exchange built on Solana; and Flux, a prediction market built on NEAR. Next month Secret Network launches their mainnet.
Finally, Mozilla laid off all but one of its full-time Rust employees. There are a few other people left at Mozilla who actively contribute to Rust as part of their role in Firefox, but this mostly ends Mozilla's commitment to Rust's development.
There's no need to worry though. Rust was designed to outlive Mozilla's withdrawal, and the project will continue nearly unaffected.

Project Spotlight

Each month we like to shine a light on a notable Rust blockchain project. This month that project is…
Fluence.
This is a blockchain with built-in software license management. We’re excited about this because license management is a rare non-currency use case for blockchains that makes a lot of sense. While we might expect to see more blockchain platforms devoted solely to digital licensing, fluence is actually a complete distributed computing platform, with a unique vision about using license management to generate profit from open source software.

Interesting Things

News

Blog Posts

Papers

Projects

Podcasts and Videos


Read more: https://rustinblockchain.org/newsletters/2020-09-02-turbofish-in-the-blocksea/
submitted by Aimeedeer to rust [link] [comments]

Nhom VBC CHROMIA AMA TRANSCRIPT (15/05/2020)

Thai Nhat Minh | Stably:
First of all, can you have a brief introduction about yourself as well as about Chromia? Henrik_hjelte, Sergelubkin
Henrik Hjelte:
Hello. My name is Henrik Hjelte. I am Co-Founder and CEO of Chromia.
I have more than 30 years of experience in programming and a degree in Economics from Uppsala University.
BTW economics and computers = blockchain, so finally found a job that fits me.
I was introduced to the blockchain by the leader of the colored-coins project Alex Mizrahi in 2013
Colored coins project was a very influential thing
It was the first way for user created tokens
bolted on to the only blockchain at the time (almost) bitcoin
We started ChromaWay 2014, with Or Perelman too, to explore if the world was interested in “tokens” and those kind of applications
We worked with enterprise blockchain for some time, but now we are focused on Chromia, a new public platform for mainstream decentralized applications using relational blockchain technology.
Ok, maybe I should tell something about Chromia and not myself too.
Chromia is a better blockchain for building decentralized Apps.
better because it follows the “normal worlds” way of managing data.
A little history: I found a text/description to paste:
Chromia is a brainchild of ChromaWay. ChromaWay has a long record of delivering pioneering projects around the world. We issued Euros on the Bitcoin blockchain with LHV bank, allowed investors to invest in startups in a wholly decentralized way with Funderbeam, digitized the title transfer process with the Swedish land registry, and mediated the green bond market. ChromaWay’s core team created the world’s first protocol to issue tokens already in 2012, when blockchain was called “bitcoin 2.0”. Then ChromaWay introduced the relational model to enterprise blockchains with a consortium database called Postchain. Now Postchain is going public as the foundation for Chromia, a better blockchain for building decentralised Apps.
Chromia is a new public blockchain based on the idea of integrating traditional databases, Relational databases with blockchain security. Chromia is a general purpose blockchain with full smart contract capabilities, just that it is a lot easier to code, even complex applications. You code with an easy to learn new programming language that combines the power of SQL and normal languages but makes it secure in a blockchain context. Up to 1/10 the code-lines vs other blockchains.
If you don’t believe me, check this blog (later, stay in the chat):
https://blog.chromia.com/reasons-for-rell-compactness/
The aim of Chromia is to combine relational databases, which exist in every kind of organization, with blockchains. We want to provide a platform for our users to develop totally decentralized apps securely. Our goal is for Chromia to be seen as the number one infrastructure for decentralized applications.
Think about it: blockchain is about managing data (in a shared context).
And… What do we use to manage data? A Database!
Serge:
Sure! My name is Serge! And I work in Chromia marketing department. Also, I help coordinate various projects inside the company
My background is in Economics and Marketing
Thai Nhat Minh | Stably:
Question 1️⃣
DApp is currently mainly concentrated in the field of games, and its life cycle is basically short, just like the Crypto Kitty is only hot for a while, how to dig the application of DApp in more fields and how to improve the utilization rate of DApp? u/henrik_hjelte u/sergelubkin
Serge:
Good one, let me answer
Gaming is quite a challenging target because good UX is expected, it needs to be fast, responsive, etc. If we can do that, then we can also do all sorts of other stuff.
Also, it lets us experiment with things without a lot of hassle, it’s easier to get users, and so on. It’s also a growing niche within blockchain. You can check our latest game, Mines of Dalarnia https://www.minesofdalarnia.com
We also have Enterprise projects already, for example Green Assets Wallet https://greenassetswallet.org/about that already launched on the first Mainnet version called Bootstrap Net,we also have https://capchap.se built on our tech, more projects like non-profit review platform Impactoria, public land registries, medical projects and so on
Also don’t forget about our fully decentralized social network/forum that is live already on the testnet https://testnet.chromunity.com.
Thai Nhat Minh | Stably:
Question 2️⃣
How will dapp face the world change after the epidemic? u/henrik_hjelte u/sergelubkin
Henrik Hjelte:
Nobody can say for sure, but maybe people will tend to be online more than offline, so demand on online products and dapps as well will increase.
I just came in from an internal demo of a secret project we do, and it can be seen as a way to hang out online (a bit cryptic answer)
There are also interesting use cases of dapps in the medical field.
For example, we participated in the world-wide hackathon Hack for Sweden. Where our submission was to create an app on Chromia blockchain that increases the coordination between countries and hospitals especially during the hard time and COVID19.
Chromia wants to help the European Union (and the world, but we saw problems in the EU…) and its citizens to provide transparency over the necessary medical and protective devices and appliances of which we see shortage during this emergency crisis.
You can watch our promo here https://twitter.com/chromaway/status/1247557274337447938?s=20.
For me it was a fun Hackathon too because for once I got the opportunity to code… I told everyone else I will not do any bossing…
We try to continue this path on medical applications a bit.
Thai Nhat Minh | Stably:
Question 3️⃣
DApps are still not directly embedded in mobile phones like Apps at this moment, and DApps have also been flooded with bet content. How can guests increase the use of DApps and lower the threshold for using DApps? u/henrik_hjelte u/sergelubkin
Serge:
The answer is — better User Experience. We believe that in order for a DApp to be usable and become more widely accepted it has to feel like a normal App. A DApp needs to have quick transactions, scale well & shouldn’t require users to pay for each transaction. This is something that is possible now with using Chromia. It’s an extremely exciting time since we are going to see a new generation of DApps.
On top of that, we think that we might have an ace coming up. We have built a game to demonstrate the powers and possibilities of Chromia. A little bit about the game: In Mines of Dalarnia (https://www.minesofdalarnia.com), players get to explore the vast expanses of interplanetary treasure mines. With an innovative Dalarnia Token system, players can purchase virtual mining plots, and put them up for rent into the community, allowing for real-estate tycoons to earn more Tokens. Mining plots can also undergo their own upgrades, making them more lucrative to explore, as well as a hot property for rental by miners. The game takes advantage of these NFT-based tokens to securely track exchanges, and provide a sense of ownership and wealth to players as they grow their mining and resource empire.
Watch our trailer https://youtu.be/bDXKOp1Asqw and sign-up for the TestNet on the website!
Thai Nhat Minh | Stably:
Question 4️⃣
Many practitioners think that the main reason for restricting the development of DApp is “incomplete infrastructure”. How effective is the current “cross-chain” and “side-chain” solution? u/henrik_hjelte u/sergelubkin
Serge:
Our infrastructure resembles Alibaba Cloud, so a DApp developer just goes and deploys his DApp’s blockchain into it, it’s easy. Also our language Rell https://rell.chromia.com/en/maste is more robust than any other blockchain programming language.Or Azure or AWS
Rell combines the following features:
  1. Relational data modeling and queries similar to SQL. People familiar with SQL should feel at home once they learn the new syntax.
  2. Normal programming constructs: variables, loops, functions, collections, etc.
  3. Constructs which specifically target application backends and, in particular, blockchain-style programming including request routing, authorization, etc.
Rell aims to make programming as convenient and simple as possible. It minimizes boilerplate and repetition. At the same time, as a static type system it can detect and prevent many kinds of defects prior to run-time.
Maybe Henrik wants to add something. :)
Henrik Hjelte:
Yes, I can add some thing
Consider again the real /normal world. What made the apps you use every day? Behind the bank app is a relational database. Web 1.0, “shopping on the internet” was a relational database hooked up to a webpage.
web 2.0: Thefacebook was PhP and MySQL hack
again, a relational database.
So, we aim to make it just as easy to do decentralized apps as normal apps.
Also “the cloud” inspiration is more normal. In Chromia, the dapp developer pays for hosting the application (normally). Not the USERS.
No gas,this is a big usability improvement.
Thai Nhat Minh | Stably:
Question 5️⃣
There are many DApp development platforms on the market. What are the competitive advantages of Chromia? It can be explained in terms of development cost and ease of use that everyone is more concerned about. u/henrik_hjelte u/sergelubkin
Henrik Hjelte:
This what I’m talking about. I think “Ease of use” combined with “Power” is our biggest strength.
Easiness is our core feature thanks to the relational database aspect of our system. Relational databases are run by 85% of the enterprise market at the moment.
And used in 100% of all organizations.
The largest vendor on that market Oracle, has a bigger market cap than bitcoin,
So, this makes it easy for enterprises to integrate our tech stack to their normal systems without the need to redo them, like in most cases where blockchain pilots have failed.
That’s partially why we had success with enterprise customer which are live in the Chromia network.
And: there is a large set of features that relational databases have that alternatives (noSQL) do not have or do not do as well.
And blockchain is very primitive compared to that.
Data indepence, mathematical foundations etc. Large books have been written about it…
On Chromiam It’s very easy for developers to deploy DApps because they already know SQL-style programming. Keep in mind that we worked with customers and developers to build our tech stack while solving problems for them. We didn’t build something unneeded, we had proof of validation from the market.
SQL is top 3rd language in the world (after HTML and javascript).
source: stackoverflow survey 2019, among 90 000 developers…
Top 4 used databases: different flavors of SQL (relational databases)
So, they are used for a reason: Ease of use/programming, power etc.
Also, Rell is our language, is statically typed (means bugs are discovered when programs are written rather than we they run). It is also more compact, up to 1/7 of the code lines of SQL. And have “normal” programming constructs + blockchain programming built in.
Because we require both relational database properties and more security than SQL, currently Rell is the only choice. It is really easy to learn, please go check https://rell.chromia.com/en/maste.
Chromia also provides news to the database developer community….
millions of developers in potential.
OK, bear this in mind when you wonder how we can compete with blockchain X… Blockchain X is a fart in the ocean compare to the SQL world 😊
Bach Tuyet
You have organized many AMA sessions to the international community in general and Vietnam in particular. What do you most want to get after AMA sessions from the community? u/henrik_hjelte
Sergey
I’ll take this one:) our goal is to grow the community
  1. We want people to join our channels such as telegram, twitter, email also our decentralized forum https://testnet.chromunity.com and participate in discussions
  2. We want people to try our dapps such as Mines of Dalarnia
  3. We want to get feedback and understand the most important issues people care about Chromia and the blockchain industry in general
  4. We want to get more developers building on top of Chromia
LBTS:
What was your motivation for creating RELL and not use other languages? What benefits? Why name it RELL also?
Henrik Hjelte:
We have a private/federated relational blockchain called Postchain, and it allows SQL. But that can work in a small environment when you know all parties, and if you are really careful in checking code. But not for a more secure, distributed on the web setup, so we had to make it more secure (Deterministic, statically typed).
In the process, we also took the opportunity to make it cool and nice.
Also: it is simply not possibly to use evm, jvm, or web assembly. We need/want a database in the bottom. Postgresql is our virtual machine. You do not reimplement that…. 10+ years codebase….
Lee:
Being part of the gamer community, I would like to know what you would think about collaborating with a MOBA, RPG or Arcade game or some kind of project?
Henrik Hjelte:
We are already collaborating with some smaller studios. For bigger fish, we want to show them what is completely unique and visionary with Chromia, and we think we need various examples. So, first arcade game MoD (linked above) is one example, it is not the full potential or anything but a start. In this summer, krystopia 2 a puzzle game from Antler Interactive will be released.
What is even cooler is the “demo project” we do together with them, where we will show how a mutliplayer game with real blockchain features will work.
I just saw it an hour ago and was blown away
OH, and there is another studio releasing something very cool. Full logic on chain strategy game. Chain of Alliance.
oyibo pepper:
Do you encourage HACKATHON programs for intending Developers to test their skills and build on RELL
Can you explain more about CHROMIA AMBASSADORS PROGRAM, CAN I BECOME AN AMBASSADOR
Serge:
Yes, you can, but you will need to change your avatar 🤣
Seriously, we are growing our Chromians community if you want to become one please ping our admins in Chromia telegram group.
Also, we are planning virtual hackathons soon, please subscribe to stay updated
Infinite Crypto:
Since the Chromia project is currently working on the Ethereum blockchain ERC20 standard!
But we know that there are a lot of scalability issues with Ethereum, so why would you choose the Ethereum blockchain over other scalable blockchains? Do you have any plans for Mainnet launch of Chromia?
Henrik Hjelte:
ETH is just used in a pre-phase for tokens. We will have our own mainnet tokens interchangable with ETH.
Oyinbo pepper
What’s CHROMIA SSO and SDK, how can I get started
Henrik Hjelte
Both are 3 letters. That is what they have in common.
SDK = software development kit, check docs on https://rell.chromia.com
SSO = single sign on. A unique UX improvement. You approve an app in your wallet (vault) with super ease. no need to remember codes
sso: https://blog.chromia.com/chromia-sso-the-whys-and-the-whats/
We have a fundamentally different model from bitcoin and ethereum and the likes. The blockchain is not run by anonymous computers in basement and student dorms across the world. We have more of known identities, so 51% attacks is protected not by PoW/PoS but other consensus. Please see our whitepaper. Note that we are not noobs when it comes to this, our CTO Alex has published papers in academic journals on consensus etc. from 2013, and done several important ideas for blockchain. Sidechains we think he was first with, tokens too.
Sheron Fernando:
Is there any plan to makes partnership with local cryptocurrency developers from each country to make $CHR usage more worldwide?
Serge:
Yes, we are looking for cooperation with more external developers. Send me a message if you are interested in developing something on Chromia.
Stella:
What are the underlying problems in the Dapps today that can be solved with the Chromia protocol?
Serge:
  1. Scalability — on Chromia your dapp can have unlimited numbers of users thanks to parallel scaling
  2. Easiness of use — you don’t need external wallets, no need to buy crypto to pay for gas etc
  3. Cost — in general to deploy the dapp and to use the dapp
Marcel Lagacé:
Why build this platform? What is Chromia mission? What are the most prominent features of the platform? Can you clarify the use case for this feature?
Henrik Hjelte:
We build the platform to fix the problems with blockchains, that we ourselves have experienced since 2014 (before ethereum existed).
LBTS:
Can you tell us about Chromia developers? How motivated and experienced are they to always deliver the best products?
Henrik Hjelte:
I can tell you that we recruit developers that are really good, from all parts of the world. Vietnam has been a hub because we found many good, so in Ukraine.
How can we say “we have so good developers”? First one thing that is a bit different is that we are pretty experienced in leadership team of development. I do not code much anymore since I’m a CEO. But I do have now over 30 years of experience. Got published and was payed when I was 15. First full-time professional developer job at 18. Have released open-source projects used by 10: s of thousand developers.
And Alex, our CTO is Extremely good. That is why I recruited him to my old startup 2006 or so… So: we have experience to sort out good developers from bad.
Marcel Lagacé:
Does Chromia staking model is different from other staking platform??
What are the beneficial advantages of chromia staking system?
Serge:
The main difference is that we have independent Providers, entities that are not connected. These serious players are exchanges, data centres, professional staking companies. They provide a backbone of the ecosystem and host dapps. Like Amazon servers in the cloud. They cannot have stake bigger than the maximum thus they can’t control the network. This is probably the main difference with classic DPoS networks
Nguyen Duy Bao:
A lot of people will want to know what the strength of Chromia is but I want to know the weaknesses and problems Chromia faces ? How do you plan to solve it?
Henrik Hjelte:
A weakness I guess is weak compared to “competition”. And there are some blockchain projects that got crazy amount of funding. So how can we compete with that, when they can hire more developers for example? Well here is what experience comes into play: More developers does not always increase productivity a lot, it is diminishing returns. You can see many large projects, with 100 of developers fail miserably with no results.
And actually, sometimes true with marketing spend too. It is generally good with money, but if you are a bit clever you can compete also on marketing with less money than your competition.
Please follow Chromia on Social Media:
Website: https://www.chromia.com
Twitter: https://twitter.com/chromia
FaceBook: https://www.facebook.com/teamchromia
LinkedIn: https://www.linkedin.com/company/chromia
Telegram: https://t.me/hellochromia
Decentralized Social network Chromunity: https://testnet.chromunity.com
Free-to-Play Blockchain Game Mines of Dalarnia: https://www.minesofdalarnia.com
submitted by dam30 to Teamchromia [link] [comments]

The economics of Bitcoin, why there hasn't been a drop in hashrate, and Blockstream's business model

To me, it seems clear as day why BTC still continues to have a significantly higher hashrate than BCH. When it comes to the reward halvings, obviously BCH's hashrate dropped because it was less profitable to mine BCH when compared to BTC. One interesting thing is that the same didn't happen to BTC at the time. I think this can be explained for a few reasons:




I'm no computer scientist, but this gives me a few ideas. I think we would all be better off if we took out the dev tax, replacing it with PURELY voluntary transaction fees. If we can voluntarily pay slightly more for a transaction, it would make more sense for miners to switch over to our network. Not only this, but I think we should voluntarily use our funds to help with development of BCH.
submitted by 1MightBeAPenguin to btc [link] [comments]

Bitcoin (BTC)A Peer-to-Peer Electronic Cash System.

Bitcoin (BTC)A Peer-to-Peer Electronic Cash System.
  • Bitcoin (BTC) is a peer-to-peer cryptocurrency that aims to function as a means of exchange that is independent of any central authority. BTC can be transferred electronically in a secure, verifiable, and immutable way.
  • Launched in 2009, BTC is the first virtual currency to solve the double-spending issue by timestamping transactions before broadcasting them to all of the nodes in the Bitcoin network. The Bitcoin Protocol offered a solution to the Byzantine Generals’ Problem with a blockchain network structure, a notion first created by Stuart Haber and W. Scott Stornetta in 1991.
  • Bitcoin’s whitepaper was published pseudonymously in 2008 by an individual, or a group, with the pseudonym “Satoshi Nakamoto”, whose underlying identity has still not been verified.
  • The Bitcoin protocol uses an SHA-256d-based Proof-of-Work (PoW) algorithm to reach network consensus. Its network has a target block time of 10 minutes and a maximum supply of 21 million tokens, with a decaying token emission rate. To prevent fluctuation of the block time, the network’s block difficulty is re-adjusted through an algorithm based on the past 2016 block times.
  • With a block size limit capped at 1 megabyte, the Bitcoin Protocol has supported both the Lightning Network, a second-layer infrastructure for payment channels, and Segregated Witness, a soft-fork to increase the number of transactions on a block, as solutions to network scalability.

https://preview.redd.it/s2gmpmeze3151.png?width=256&format=png&auto=webp&s=9759910dd3c4a15b83f55b827d1899fb2fdd3de1

1. What is Bitcoin (BTC)?

  • Bitcoin is a peer-to-peer cryptocurrency that aims to function as a means of exchange and is independent of any central authority. Bitcoins are transferred electronically in a secure, verifiable, and immutable way.
  • Network validators, whom are often referred to as miners, participate in the SHA-256d-based Proof-of-Work consensus mechanism to determine the next global state of the blockchain.
  • The Bitcoin protocol has a target block time of 10 minutes, and a maximum supply of 21 million tokens. The only way new bitcoins can be produced is when a block producer generates a new valid block.
  • The protocol has a token emission rate that halves every 210,000 blocks, or approximately every 4 years.
  • Unlike public blockchain infrastructures supporting the development of decentralized applications (Ethereum), the Bitcoin protocol is primarily used only for payments, and has only very limited support for smart contract-like functionalities (Bitcoin “Script” is mostly used to create certain conditions before bitcoins are used to be spent).

2. Bitcoin’s core features

For a more beginner’s introduction to Bitcoin, please visit Binance Academy’s guide to Bitcoin.

Unspent Transaction Output (UTXO) model

A UTXO transaction works like cash payment between two parties: Alice gives money to Bob and receives change (i.e., unspent amount). In comparison, blockchains like Ethereum rely on the account model.
https://preview.redd.it/t1j6anf8f3151.png?width=1601&format=png&auto=webp&s=33bd141d8f2136a6f32739c8cdc7aae2e04cbc47

Nakamoto consensus

In the Bitcoin network, anyone can join the network and become a bookkeeping service provider i.e., a validator. All validators are allowed in the race to become the block producer for the next block, yet only the first to complete a computationally heavy task will win. This feature is called Proof of Work (PoW).
The probability of any single validator to finish the task first is equal to the percentage of the total network computation power, or hash power, the validator has. For instance, a validator with 5% of the total network computation power will have a 5% chance of completing the task first, and therefore becoming the next block producer.
Since anyone can join the race, competition is prone to increase. In the early days, Bitcoin mining was mostly done by personal computer CPUs.
As of today, Bitcoin validators, or miners, have opted for dedicated and more powerful devices such as machines based on Application-Specific Integrated Circuit (“ASIC”).
Proof of Work secures the network as block producers must have spent resources external to the network (i.e., money to pay electricity), and can provide proof to other participants that they did so.
With various miners competing for block rewards, it becomes difficult for one single malicious party to gain network majority (defined as more than 51% of the network’s hash power in the Nakamoto consensus mechanism). The ability to rearrange transactions via 51% attacks indicates another feature of the Nakamoto consensus: the finality of transactions is only probabilistic.
Once a block is produced, it is then propagated by the block producer to all other validators to check on the validity of all transactions in that block. The block producer will receive rewards in the network’s native currency (i.e., bitcoin) as all validators approve the block and update their ledgers.

The blockchain

Block production

The Bitcoin protocol utilizes the Merkle tree data structure in order to organize hashes of numerous individual transactions into each block. This concept is named after Ralph Merkle, who patented it in 1979.
With the use of a Merkle tree, though each block might contain thousands of transactions, it will have the ability to combine all of their hashes and condense them into one, allowing efficient and secure verification of this group of transactions. This single hash called is a Merkle root, which is stored in the Block Header of a block. The Block Header also stores other meta information of a block, such as a hash of the previous Block Header, which enables blocks to be associated in a chain-like structure (hence the name “blockchain”).
An illustration of block production in the Bitcoin Protocol is demonstrated below.

https://preview.redd.it/m6texxicf3151.png?width=1591&format=png&auto=webp&s=f4253304912ed8370948b9c524e08fef28f1c78d

Block time and mining difficulty

Block time is the period required to create the next block in a network. As mentioned above, the node who solves the computationally intensive task will be allowed to produce the next block. Therefore, block time is directly correlated to the amount of time it takes for a node to find a solution to the task. The Bitcoin protocol sets a target block time of 10 minutes, and attempts to achieve this by introducing a variable named mining difficulty.
Mining difficulty refers to how difficult it is for the node to solve the computationally intensive task. If the network sets a high difficulty for the task, while miners have low computational power, which is often referred to as “hashrate”, it would statistically take longer for the nodes to get an answer for the task. If the difficulty is low, but miners have rather strong computational power, statistically, some nodes will be able to solve the task quickly.
Therefore, the 10 minute target block time is achieved by constantly and automatically adjusting the mining difficulty according to how much computational power there is amongst the nodes. The average block time of the network is evaluated after a certain number of blocks, and if it is greater than the expected block time, the difficulty level will decrease; if it is less than the expected block time, the difficulty level will increase.

What are orphan blocks?

In a PoW blockchain network, if the block time is too low, it would increase the likelihood of nodes producingorphan blocks, for which they would receive no reward. Orphan blocks are produced by nodes who solved the task but did not broadcast their results to the whole network the quickest due to network latency.
It takes time for a message to travel through a network, and it is entirely possible for 2 nodes to complete the task and start to broadcast their results to the network at roughly the same time, while one’s messages are received by all other nodes earlier as the node has low latency.
Imagine there is a network latency of 1 minute and a target block time of 2 minutes. A node could solve the task in around 1 minute but his message would take 1 minute to reach the rest of the nodes that are still working on the solution. While his message travels through the network, all the work done by all other nodes during that 1 minute, even if these nodes also complete the task, would go to waste. In this case, 50% of the computational power contributed to the network is wasted.
The percentage of wasted computational power would proportionally decrease if the mining difficulty were higher, as it would statistically take longer for miners to complete the task. In other words, if the mining difficulty, and therefore targeted block time is low, miners with powerful and often centralized mining facilities would get a higher chance of becoming the block producer, while the participation of weaker miners would become in vain. This introduces possible centralization and weakens the overall security of the network.
However, given a limited amount of transactions that can be stored in a block, making the block time too longwould decrease the number of transactions the network can process per second, negatively affecting network scalability.

3. Bitcoin’s additional features

Segregated Witness (SegWit)

Segregated Witness, often abbreviated as SegWit, is a protocol upgrade proposal that went live in August 2017.
SegWit separates witness signatures from transaction-related data. Witness signatures in legacy Bitcoin blocks often take more than 50% of the block size. By removing witness signatures from the transaction block, this protocol upgrade effectively increases the number of transactions that can be stored in a single block, enabling the network to handle more transactions per second. As a result, SegWit increases the scalability of Nakamoto consensus-based blockchain networks like Bitcoin and Litecoin.
SegWit also makes transactions cheaper. Since transaction fees are derived from how much data is being processed by the block producer, the more transactions that can be stored in a 1MB block, the cheaper individual transactions become.
https://preview.redd.it/depya70mf3151.png?width=1601&format=png&auto=webp&s=a6499aa2131fbf347f8ffd812930b2f7d66be48e
The legacy Bitcoin block has a block size limit of 1 megabyte, and any change on the block size would require a network hard-fork. On August 1st 2017, the first hard-fork occurred, leading to the creation of Bitcoin Cash (“BCH”), which introduced an 8 megabyte block size limit.
Conversely, Segregated Witness was a soft-fork: it never changed the transaction block size limit of the network. Instead, it added an extended block with an upper limit of 3 megabytes, which contains solely witness signatures, to the 1 megabyte block that contains only transaction data. This new block type can be processed even by nodes that have not completed the SegWit protocol upgrade.
Furthermore, the separation of witness signatures from transaction data solves the malleability issue with the original Bitcoin protocol. Without Segregated Witness, these signatures could be altered before the block is validated by miners. Indeed, alterations can be done in such a way that if the system does a mathematical check, the signature would still be valid. However, since the values in the signature are changed, the two signatures would create vastly different hash values.
For instance, if a witness signature states “6,” it has a mathematical value of 6, and would create a hash value of 12345. However, if the witness signature were changed to “06”, it would maintain a mathematical value of 6 while creating a (faulty) hash value of 67890.
Since the mathematical values are the same, the altered signature remains a valid signature. This would create a bookkeeping issue, as transactions in Nakamoto consensus-based blockchain networks are documented with these hash values, or transaction IDs. Effectively, one can alter a transaction ID to a new one, and the new ID can still be valid.
This can create many issues, as illustrated in the below example:
  1. Alice sends Bob 1 BTC, and Bob sends Merchant Carol this 1 BTC for some goods.
  2. Bob sends Carols this 1 BTC, while the transaction from Alice to Bob is not yet validated. Carol sees this incoming transaction of 1 BTC to him, and immediately ships goods to B.
  3. At the moment, the transaction from Alice to Bob is still not confirmed by the network, and Bob can change the witness signature, therefore changing this transaction ID from 12345 to 67890.
  4. Now Carol will not receive his 1 BTC, as the network looks for transaction 12345 to ensure that Bob’s wallet balance is valid.
  5. As this particular transaction ID changed from 12345 to 67890, the transaction from Bob to Carol will fail, and Bob will get his goods while still holding his BTC.
With the Segregated Witness upgrade, such instances can not happen again. This is because the witness signatures are moved outside of the transaction block into an extended block, and altering the witness signature won’t affect the transaction ID.
Since the transaction malleability issue is fixed, Segregated Witness also enables the proper functioning of second-layer scalability solutions on the Bitcoin protocol, such as the Lightning Network.

Lightning Network

Lightning Network is a second-layer micropayment solution for scalability.
Specifically, Lightning Network aims to enable near-instant and low-cost payments between merchants and customers that wish to use bitcoins.
Lightning Network was conceptualized in a whitepaper by Joseph Poon and Thaddeus Dryja in 2015. Since then, it has been implemented by multiple companies. The most prominent of them include Blockstream, Lightning Labs, and ACINQ.
A list of curated resources relevant to Lightning Network can be found here.
In the Lightning Network, if a customer wishes to transact with a merchant, both of them need to open a payment channel, which operates off the Bitcoin blockchain (i.e., off-chain vs. on-chain). None of the transaction details from this payment channel are recorded on the blockchain, and only when the channel is closed will the end result of both party’s wallet balances be updated to the blockchain. The blockchain only serves as a settlement layer for Lightning transactions.
Since all transactions done via the payment channel are conducted independently of the Nakamoto consensus, both parties involved in transactions do not need to wait for network confirmation on transactions. Instead, transacting parties would pay transaction fees to Bitcoin miners only when they decide to close the channel.
https://preview.redd.it/cy56icarf3151.png?width=1601&format=png&auto=webp&s=b239a63c6a87ec6cc1b18ce2cbd0355f8831c3a8
One limitation to the Lightning Network is that it requires a person to be online to receive transactions attributing towards him. Another limitation in user experience could be that one needs to lock up some funds every time he wishes to open a payment channel, and is only able to use that fund within the channel.
However, this does not mean he needs to create new channels every time he wishes to transact with a different person on the Lightning Network. If Alice wants to send money to Carol, but they do not have a payment channel open, they can ask Bob, who has payment channels open to both Alice and Carol, to help make that transaction. Alice will be able to send funds to Bob, and Bob to Carol. Hence, the number of “payment hubs” (i.e., Bob in the previous example) correlates with both the convenience and the usability of the Lightning Network for real-world applications.

Schnorr Signature upgrade proposal

Elliptic Curve Digital Signature Algorithm (“ECDSA”) signatures are used to sign transactions on the Bitcoin blockchain.
https://preview.redd.it/hjeqe4l7g3151.png?width=1601&format=png&auto=webp&s=8014fb08fe62ac4d91645499bc0c7e1c04c5d7c4
However, many developers now advocate for replacing ECDSA with Schnorr Signature. Once Schnorr Signatures are implemented, multiple parties can collaborate in producing a signature that is valid for the sum of their public keys.
This would primarily be beneficial for network scalability. When multiple addresses were to conduct transactions to a single address, each transaction would require their own signature. With Schnorr Signature, all these signatures would be combined into one. As a result, the network would be able to store more transactions in a single block.
https://preview.redd.it/axg3wayag3151.png?width=1601&format=png&auto=webp&s=93d958fa6b0e623caa82ca71fe457b4daa88c71e
The reduced size in signatures implies a reduced cost on transaction fees. The group of senders can split the transaction fees for that one group signature, instead of paying for one personal signature individually.
Schnorr Signature also improves network privacy and token fungibility. A third-party observer will not be able to detect if a user is sending a multi-signature transaction, since the signature will be in the same format as a single-signature transaction.

4. Economics and supply distribution

The Bitcoin protocol utilizes the Nakamoto consensus, and nodes validate blocks via Proof-of-Work mining. The bitcoin token was not pre-mined, and has a maximum supply of 21 million. The initial reward for a block was 50 BTC per block. Block mining rewards halve every 210,000 blocks. Since the average time for block production on the blockchain is 10 minutes, it implies that the block reward halving events will approximately take place every 4 years.
As of May 12th 2020, the block mining rewards are 6.25 BTC per block. Transaction fees also represent a minor revenue stream for miners.
submitted by D-platform to u/D-platform [link] [comments]

tBTC an erc20 wrapped version of BTC, like erc20 wBTC; but is trustless and does not require a centralised party to mint wrapped btc like wBTC

I found this article on /Ethereum though it didnt go into the specs of how this works:
https://np.reddit.com/ethereum/comments/ftqdna/bitcoin_to_ethereum_bridge_raises_77_million_in/
https://decrypt.co/24336/bitcoin-to-ethereum-bridge-raises-7-7-million-in-token-sale?utm_source=reddit&utm_medium=social&utm_campaign=sm
as the article says wrapped bitcoin has been done before e.g. wBTC but wBTC requires a centralised party to mint wBTC from BTC held by this party; making it out of the question as its centralised.
did some digging there is a whitepaper , but i wanted more details on the tBTC implementation.
I went on their github and looked at the readme on some projects; found a few interesting things, though not an entire explanation.
https://github.com/keep-network/tbtc
tBTC is a trustlessly Bitcoin-backed ERC-20 token.
The goal of the project is to provide a stronger 2-way peg than federated sidechains like Liquid, expanding use cases possible via today’s Bitcoin network, while bringing superior money to other chains.
This repo contains the Solidity smart contracts and specification.
https://github.com/keep-network/tbtc
tbtc.js provides JS bindings to the tBTC system. The tBTC system is a bonded, multi-federated peg made up of many deposits backed by single-use BTC wallets to enable their value’s corresponding usage on the Ethereum chain, primarily through the minting of a TBTC ERC20 token whose supply is guaranteed to be backed by at least 1 BTC per TBTC in circulation.
finally this is the best:
https://tbtc.network/developers/tbtc-technical-system-overview
here is the first few pargarphs
2020-04-01 tBTC incorporates novel design features that carry important implications for users. This piece explains four of these: TDT receipts, multiple lot sizes, Keep's random beacon, and threshold signatures.
TBTC Deposit Token (TDT) The TBTC Deposit Token (TDT) is a non-fungible token that is minted when a user requests a deposit. A TDT is a non-fungible ERC-721 token that serves as a counterpart to TBTC. It represents a claim to a deposit's underlying UTXO on the Bitcoin blockchain.
TBTC deposits can be locked or unlocked. A locked deposit can only be redeemed by the deposit owner with the corresponding TDT. Each TDT is unique to the deposit that mints it and carries the exclusive right for up to a 6 month term to redeem the deposit.
also this paragraph addresses creating wallets with the created tokens
Random Beacon for Signer Selection
The Keep network requires a trusted source of randomness to select tBTC signers. This takes the form of a BLS Threshold Relay.
When a request comes in to create a signing group, the tBTC system uses a random seed from a secure decentralized random beacon to randomly select signing group members from the eligible pool of signers. These signers coordinate a distributed key generation protocol that results in a public ECDSA key for the group, which is used to produce a wallet address that is then published to the host chain. This completes the signer selection phase.
my take away from this is that by using side chains that a trustless, not fedeared like liquid bitcoin sidechains sold by blockstream. it uses NFT erc-721 tokens as representation of the bitccoin UTXO from the bitcoin blockchain, store it in a wallet and mint it into tBTC. given this is all smart contracts generating wallets and minting the tBTC, it does away with the need of a centralised party to provide the funds of BTC to create a wrapped erc20 version on ethereum and so should be trustles.
perhaps erc20 token trading is the way to go forward. just requires wrapping of exisitng tokens. this looks promising for DeXs and DeFi if it happens.
also opens the possibiliy of multicollateral Dai (MCD) using tBTC in addition to eth and BAT. though personally i think btc should not be used in MCD.
any thoughts on this? or if my understanding is off.
thanks
edit: got some more info from px403
I talked to James a bit about tBTC in Osaka, so I have a vague idea of how it works, so I might be able to explain it in a somewhat coherent way.
Basically, the magic here is they reimplemented Bitcoin's SPV as an Ethereum smart contract, effectively letting them query the current state of the Bitcoin network, including validity of payments, directly in contract. Using this, they built an auction system where people can at any time claim ETH by paying BTC, or claim BTC by paying ETH. By design the spread is wide, so this isn't actually intended to be a high volume exchange, but what you do get is a pretty good price oracle.
From the price oracle, I think there were doing some Maker style CDPs or something, where people could lock up their BTC on the Bitcoin network to redeem tBTC, and any of the locked BTC could be reclaimed by burning tBTC or something.
Sorry it's not a complete picture of what's going on, but I think that's the general gist of what they're doing.
submitted by Neophyte- to CryptoTechnology [link] [comments]

Re-Launching The Borderless, Unkillable Crypto-Fiat Gateway, DAIHard. Enter or Exit Crypto via Any Fiat and Any Payment Method, Anywhere in the World, Without KYC. All you need is a little Dai.

Some of you might recall recall our initial facepalm failed launch about 3 months ago (post-mortem here). Well, we're back--this time with an audit and some new features. This version of DAIHard should should die a little harder this time ;)

The Audit

After shopping around a bit in the auditor space, we decided to go with Adam Dossa--the very same Adam Dossa that actually found our launch vulnerability and responsibly disclosed it to us! You can see his report here. By the way, Adam has been a gem: friendly, professional, timely, and flexible. Definitely keep him in mind if you need an audit!

(Re)Introducing DAIHard

Following is an updated version of our original launch post. If you've already read that, you might want to skip to the heading What's New in v0.9.2. Or you can go straight to the app or go to our info site for more info!
Here is a legitimate concern most of us are familiar with:
To enter or exit the crypto economy, we rely on centralized exchanges such as Coinbase, which track their users, impose limits, and are tightly coupled to their jurisdiction and its banking system. And for all we know, any day now regulations could start tightening these controls further (*we've actually seen some of this play out in the two months since our first launch post). In light of this, can we say in any meaningful sense that crypto is anonymous, limtiless, borderless, immune to regulation, and (most importantly) unstoppable?
To really address this concern, we need a completely decentralized gateway between fiat and crypto: something that extends the benefits of crypto to the very act of moving between the old and new economies. But the design of such a platform is far from obvious.
(Localethereum comes close, but as discussed under Unkillable, it doesn't quite cut it. And Bisq is decentralized, but has significant UX hurdles.)
We believe we've found a solution. We are proud to present:

DAIHard v0.9.2 - Almost Definitely Not Broken This Time

If you want to jump right in, we recommend first watching our latest usage demo (7 min), then diving in and giving it a shot with a small amount of Dai. (Try it on Kovan first if mainnet is too scary!)
DAIHard extends many of the promises of crypto (borderless, anonymous, limitless, unstoppable) into the exchange mechanism itself, allowing anyone, anywhere to bypass centralized exchanges and the control they impose.
More concretely, DAIHard is a platform, run on smart contracts, for forming one-off crypto/fiat exchanges with other users, in which:
Again, our latest usage demo (7 min) shows this process in action.

Two drawbacks

You Need either xDai, or both Dai and Ether, to Use The Tool (At Least For Now)

If you want to buy Dai on DAIHard, you must already have Dai--1/3 of the amount you want to purchase--to put up as a burnable deposit. For example, if you only have 10 Dai now, you can only commit to buying 30 Dai, and must complete that trade before using the newly bought Dai to open up a bigger offer (for up to 120 Dai that time).
Most tragically of course, this means that if you don't already have some crypto, you can't use this tool to get crypto--this is why we avoid calling DAIHard an onramp specifically. This comes from the fact that both parties must have "skin in the game" for the game theory to work, and a smart contract can only threaten to burn crypto.
We have some ideas on how to address this drawback in the not-too-distant future, which we'll write about soon. For now it's time to launch this thing and get some users!

Dangerous and Scary To Use

In rare cases, a user may have to burn Dai and face a loss on the entire trade amount. The necessity of this ever-present risk is explained in detail in DAIHard Game Theory.
However, a cautious, rational user can gather information (possibly via our [subreddit](daihard)!) about how people have used the tool, successfully and unsuccessfully. They can then create a buy or sell offer with wisely chosen settings based on what has worked for others. Other cautious, rational users can find this offer and commit to the trade if they dare. We expect the vast majority of committed trades should involve rational, cautious users, and should therefore resolve happily.
Still, inevitably there will be sloppy trades that result in burns. As the tool is used, we'll be keeping a close eye on the frequency of burns and keeping you guys updated (perhaps via a "System Status" utility similar to the one found on MakerDao's explorer). In the end, though, we expect the risk in using DAIHard to be comparable to the risk of using any exchange or DNM: ever-present but low enough for the platform to be useful as whole.
So, while DAIHard will never shut down and can't perform an exit scam, the bad news is it's not risk-free. Users will have to approach DAIhard with the same level of caution they would with any new exchange (albeit for different reasons and with a different approach).
So what's the good news?

The Good News

While these drawbacks are significant, they enable some remarkable features that no other crypto/fiat exchange mechanism can boast.

Unkillable

(Correction: Bisq seems to have a decentralized arbitration system)
We are aware of no other crypto/fiat exchange platform that is truly unkillable. Bisq and localethereum comes close, but both localethereum relies on centralized processes of arbitration. This means their fraud-and-scam-prevention system can be sued, jailed, or otherwise harrassed--and if that part stops working, it doesn't matter how decentralized the rest of the system was.
DAIHard, in contrast, gives the users the power to police and punish each other, via the aforementioned credible threat of burn. This is simple game theory, and the rules of this game are etched permanently into the DAIHard Factory and Trade contract code: impervious to litigation, regulation, and political pressure.
This Factory contract has no owner and no suicide or pause code. It cannot be stopped by us or anyone else.
Like Toastycoin, this thing was immortal the moment it was deployed (even more immortal than RadarRelay, for example, which does rely on an ownership role). Both DAIHard and Toastycoin (and probably whatever we build next) will last for as long as a single Ethereum node continues mining, and it will remain easy to use as long as someone can find the HTML/JS front-end and a web3 wallet.
(The HTML/JS front-end (built in Elm, by the way, with the lovely elm-ethereum!) is currently hosted on Github pages, which is centralized--but even if Github takes down the page and deletes the code, it's a minor step to get the page hosted on IPFS, something that is on our near-term roadmap in any case)

No KYC, No Limits

It's smart contracts all the way down, so DAIHard never asks any nosy questions--if you have Metamask or some other web3 wallet installed and set up, with some ETH and Dai (or just xDai), you can immediately open or commit to a trade. You don't even need a username!
(In fact, we're so inclusive, even machines are allowed--no CAPTCHA here!)
You're limited only by the collateral you put up, so if you have 10,000 Dai you could open up a buy offer for 30,000 Dai (or a sell offer for 10,000 Dai) right now.
We do reccommend trying the tool out first with a small amount of Dai... But we're not your mom! Do what you want!

Borderless

It simply doesn't matter where you are, because DAIHard doesn't need to interface with any particular jurisdiction or payment system to work. DIAHard works by incentivizing people (or robots?) to navigate the particular real-world hurdles of bank transfers, cash drops, or other fiat transfer methods. These incentives work whether you're in America, Zimbabwe, or the Atlantic; they work whether the fiat is USD, EUR, ZAR, seashells, or Rai Stones; and they work whether your counterparty is a human, an organization, a script, or a particularly intelligent dog with Internet access.

Any Fiat Type, and Highly Customizeable

Here are some examples of the types of trades you might create or find on DAIHard.
As the DAIHard community grows, users will doubtless find much more creative ways to use the system, and we will discover together which types of trades are reliable and which are more risky. Because users can set their own prices and phase timeout settings, we expect the risky trades to charge a premium or have longer time windows, while the reliable ones rapidly multiply at close to a 1:1 price ratio, with quick turnaround times.

Extensible (with profit) by Third Parties

Not satisfied with our interface? Do you have some nifty idea for how to display and organize user reputation? Or maybe some idea for how trades could be chained togeher? Maybe you'd like to design a notification system for DAIHard? Maybe you just want a different color scheme!
Well, you won't need our permission to do any of this. Any tool that watches the same Factory contract will share the pool of trades, regardless of which tool actually creates the trade. This means we don't even have to fight over network effects!
And if you look closely at our fee structure, you might notice that only half of the 1% DAIHard fee is "hardcoded" into the Factory contract. The other half is set and charged by our interface. What does this mean for you? If you go out and make a better interface, you can essentially replace half of our 1% fee with your own fee--it's up to you whether it's smaller or larger than the replaced 0.5%.
The reason for this is to explicitly welcome other developers to extend what we've built. For as long as our team is the only one improving the platform, a threat to us is a threat to future upgrades. But if others begin extending the DAIHard platform too, then DAIHard will not only be unstoppable as it is today, but also grow unstoppably.

(For Real This Time) This Is a Big Fucking Deal

DAIHard is a turning point in crypto and a breakthrough in decentralized markets, and is an irreversible augmentation of the Ethereum platform.
What we've built is a gateway to crypto completely devoid of centralized components--rendering entry and exit to crypto unkillable, flexible, borderless, and private. Centralized exchanges, and the control they impose, can now be bypassed by anyone with Dai and a web3 wallet.

What's New in v0.9.2

There have been many changes made since our first failed launch, but there are two rather important ones: xDai support and reputation tools.

xDai support

DAIHard is now operational on xDai, a sidechain whose native token (xDai) is pegged to the Dai (and therefore $1). Add the xDai network to your Metamask (or just install Nifty Wallet), then switch to the xDai network in your wallet, to try it out. xDai has some pretty incredible benefits, compared to vanilla Ethereum:

Reputation tools

We now have a few reputation tools. First, on any open trade, there is a widget showing the number of releases, aborts, and burns the given address has been involved in as that role (buyer or seller). Clicking on this expands the widget to show more detailed information, and also provides a link to a page that lists each trade this user has been or is involved in.

What's next?

We have tons of ideas on how to improve the product--too many, in fact, to commit to any before we get a good chunk of user feedback. Here are some of our favorite ideas:

Near-Term, Smaller Features

  1. Lots of usability improvements.
  2. A "System Status" utility similar to the one found on MakerDao's explorer).
  3. Marketplace / My Trades rework.
  4. A "QuickTrade" page, offering Trade Templates as an alternative to the current Create Offer page.

Big Exciting Features

  1. Bootstrapping people with no DAI via other mechanisms and community outreach.
  2. Partial commits to trades. eg. Place a 10,000 DAI trade and allow it to be picked up in blocks larger than 500 DAI at a time.
  3. More chains, get this thing working on Bitcoin via Rootstock, on Ethereum Classic and Binance Chain.

Stay Informed!

A lot of the above features will be prioritized more clearly as we get user feedback, and we will be posting fairly frequent updates and articles on our info site. If you don't want to miss anything, note the subscribe widget and sign up!
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