23 votes
Accepted

UTXO model vs. account/balance model

The choice between the UTXO model and the balance model is primarily one between privacy incentives and apparent intuitiveness. If one follows the standard advice of not reusing addresses/outputs/...
Pieter Wuille's user avatar
12 votes

Is it correct to say that Bitcoin has a virtual machine in the same way as Ethereum does?

"Virtual machine" in this context is really just a fancy word for bytecode interpreter. Bitcoin's script language is certainly far simpler than Ethereum's EVM, and its functionalities are in ...
Pieter Wuille's user avatar
9 votes

What are the differences (and value adds) among all the different Crypto Currencies?

99% of altcoins claim an "innovation" that is broken or unproven. I would say that the first thing to do is look at unique codebases that aren't based on Bitcoin, which basically means (besides ...
Нонн Болдырев's user avatar
9 votes
Accepted

In Ethereum, what is an uncle block?

An uncle is a block that, in bitcoin, would be considered a stale block because it is not on the longest chain (it's an alternative block at the same height as your parent). Ethereum incentivizes ...
user2716556's user avatar
8 votes

What is Gas Limit in Ethereum?

The current gas limit can be checked on the network stats page. It's currently 3,141,592 (pi million). The gas limit per block is not fixed, though. The number of contract calls and standard ...
q9f's user avatar
  • 1,444
8 votes
Accepted

Is there a pro vs con chart comparing Bitcoin's Rootstock vs Ethereum Smart Contract system?

Rootstock's smart contract features are identical to Ethereum's, both use the EVM. Contracts on Ethereum are deployable on Rootstock, and vice versa. They start to differ when you look at the ...
Steve Ellis's user avatar
  • 1,062
8 votes

How does using a Turing-complete programming language compromise the security of the network?

It is much easier to formally verify the behavior space of Bitcoin script vs. Solidity. For example, the DAO project suffered from reentrancy vulnerabilities, given that one could not predict the ...
James C.'s user avatar
  • 2,511
8 votes
Accepted

If the nonce is 32 bits why the proof of it is difficult?

The vast majority of the time, none of the 2^32 possible nonces in a particular block header template will result in the header having a hash that meets the proof-of-work target. In fact, the ...
Nate Eldredge's user avatar
7 votes

What are the differences (and value adds) among all the different Crypto Currencies?

A very large majority of these altcoins are essentially scams. There is a cottage industry that takes a coin, changes something minor (name, logo), and releases it with great fanfare, enticing people ...
user36303's user avatar
  • 786
7 votes
Accepted

Does bitcoin have the potential to be subject to a hard fork where miners are forced to choose which fork they will accept, like Etherum?

Yes, Bitcoin could also be subjected to a hardfork. In fact, there are members of the Bitcoin community that feel so strongly that the blocksize should be increased that they are proposing to do just ...
Murch's user avatar
  • 74.5k
7 votes
Accepted

In what sense does the security model of proof-of-stake require users to "log on to the internet every few months"

What Vitalik is talking about is the Slasher algorithm that he designed which punishes the block signer if he attempts to create a fork in the blockchain. However the way that slasher works is that ...
Ava Chow's user avatar
  • 70k
7 votes
Accepted

Does Bitcoin Blockchain solves Byzantine General Problem?

The Proof of Work algorithms is a probabilistic solution to the Byzantine General's problem in the case where traitorous generals represent strictly less than 50% of the generals. To simplify, the ...
Aymen's user avatar
  • 231
6 votes
Accepted

Does ethereum run on the bitcoin blockchain?

Bitcoin and Ethereum have different and unique blockchains. They have no relationship (other than the fact that Ethereum and all other cryptcurrencies based their design on the Bitcoin blockchain).
karask's user avatar
  • 2,530
6 votes

What is the approach to calculate an Ethereum address from a 256 bit private key?

Start with the public key bytes (a bytestring of length 64) Of that public key, take the Keccak-256 hash used ubiquitously by Ethereum (make sure you get that right, as the ultimately standardized ...
Steve Waldman's user avatar
6 votes
Accepted

What database engine does Bitcoin and other top altcoins use?

It depends on the implementation. The network itself does not have a database engine. Bitcoin Core and software derived from it (most altcoin software is derived from Core) uses LevelDB to index the ...
Ava Chow's user avatar
  • 70k
6 votes

Etherium based tokens

It is completely different. Ethereum offers a standardized way to create new tokens on its blockchain called the ERC-20 protocol. ERC-20 is not a piece of code, software, or technology. Rather, it is ...
Ankur Gupta's user avatar
5 votes
Accepted

What is the DAO, and what is its connection with Ethereum

So what is the DAO's connection with Ethereum, and what is its purpose? The DAO was a decentralized autonomous organization designed to invest in DAPPs built on Ethereum Why is the operation of the ...
John's user avatar
  • 271
5 votes
Accepted

Problem of colored-coins/assets and other coins with a parent/child relationship of paying for fees with only the parent currency

It's definitely a common problem found in a lot of those platforms that make it easy to create your own colored coin/token. Asking users to acquire the native token, such as Bitcoin with Counterparty ...
T.K's user avatar
  • 281
5 votes

How are eth transaction faster than btc?

Most simple and foreseen reason: Bitcoin's blocktime is set at 10 minutes, while Ethereum has a block every 10-20 seconds, making it much faster. See Ghost protocol, https://www.cryptocompare.com/...
Rutger Versteegden's user avatar
5 votes
Accepted

When does Ardor smart contracts come into effect and how does it work compared to Ethereum, EOS, and Lisk?

First off, Lisk doesn't have full turing-complete smart contracts so there isn't much of a comparison on that front. Key shortcomings of existing frameworks like Ethereum can be summarized by five ...
demetriuss's user avatar
5 votes
Accepted

Why are there ETH addresses in bitcoin wallet.dat?

Ethereum addresses are the trailing 20 bytes of keccak256(public_key). In other words, ethereum addresses are any collection of 20 bytes. 0014{20 byte payload} in Bitcoin is the redeem script for a ...
Raghav Sood's user avatar
4 votes
Accepted

Is Ethereum essentially Bitcoin with Turing-complete Script?

Is Ethereum essentially Bitcoin with a Turing-complete scripting language and, if I understand correctly, where the script to be executed (not its hash) is placed in the Ethereum blockchain? That's a ...
Nick ODell's user avatar
  • 29.4k
4 votes
Accepted

Why are Virtual Machines used in Ethereum?

note: I might be wrong The EVM is actually the core of Ethereum. All contracts are written in EVM bytecode. This doesn't mean that Ethereum includes an actual virtual machine in the sense of Hyper-V, ...
GiM's user avatar
  • 156
4 votes

Restore Wallet From Jaxx to Coinomi: ETH missing (but BTC and LTC are fine)

Jaxx uses a different derivation path than Coinomi when handling ETH. Coinomi opted for the path as described in the ETH specification. Ledger has the same scheme as Coinomi. Jaxx: M/44H/60H/0H/0 ...
angelitto's user avatar
4 votes

Ethereum Code bots...Scam or not?

promising 13k a day It is almost certainly a scam. Stay well away from this. I need to play it safe ... I simply cant afford Don't invest in volatile high-risk products such as crypto-currencies.
RedGrittyBrick's user avatar
4 votes

Does Bitcoin Blockchain solves Byzantine General Problem?

The Byzantine Generals' Problem Imagine a time during the dark ages, where a pirate ship is under attack. There are 200 pirates aboard the pirate ship surrounded by six army ships of 50 warriors each,...
Chirag Maliwal's user avatar
4 votes

Accepting Bitcoin for Services Rendered with Legal Verbiage on Set Coin Price

If you want to go all in on cryptocurrency, you can make an agreement stating the payment method as BTC or ETH and then the amount. The value of these currencies may vary with time and hence no one ...
Junaid Shaikh's user avatar
4 votes
Accepted

How is a node selected to run Smart Contract in Ethereum

A node that runs a smart contract will be paid with GAS. This is incorrect. The miner who mines the block containing the transaction interacting with a contract is the one who is paid with ETH, which ...
Raghav Sood's user avatar
4 votes

How to model randomness in validators selection in PoS?

I understand it is a random selection based on fraction of stake a validator has, similar to PoW. Not correct. In PoW, any miner can mine the next block. In PoS, a specific validator is chosen by the ...
Ugam Kamat's user avatar
  • 7,398
3 votes
Accepted

Are there Ethereum API wrappers?

Not yet. We've just revamped the server side RPC internals in develop and are still ironing out some quirks. I can imagine we would soon-ish start working towards the directions of providing some Go ...
Péter Szilágyi's user avatar

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