29 votes
Accepted

What's a Sybil attack?

A Sybil attack is an attack where a single adversary is controlling multiple nodes on a network. It is unknown to the network that the nodes are controlled by the same adversarial entity. For example, ...
dionyziz's user avatar
  • 1,012
21 votes
Accepted

What is the difference between Dogecoin and Bitcoin at the network level?

TL;DR: small code differences, but many larger ecosystem differences IIRC, Dogecoin is a fork of Luckycoin, which in turn was forked from Litecoin, which was forked from Tenebrix, which was forked ...
Murch's user avatar
  • 72.7k
17 votes
Accepted

Bitcoin without mining - what needs to be implemented

Mining is not essential for coin creation. New coin introduction can be tied to new block creation, or be time based. Even if you don't use proof of work, you will still have blocks (even if you don't ...
Pieter Wuille's user avatar
7 votes

Why is my transaction immature?

Block rewards (coinbase outputs) can't be spent for 100 blocks. This is called "maturity" in the codebase and is to protect some behavior around reorganizations.
Claris's user avatar
  • 15.4k
6 votes

What is needed to get listed on a currency exchange website?

First, you're going to have to prove that your altcoin is useful and has value and liquidity. You can't just create a new coin and expect people to value it. The most successful altcoins have ...
Jimmy Song's user avatar
  • 7,749
5 votes

How do you make a coin resistant to soft forking?

You can't prevent miners from enforcing more rules than the rest of the network is. However, to actually turn that into a soft fork, a significant portion of the network also needs to start enforcing ...
Pieter Wuille's user avatar
5 votes

How to generate Ed25519 public key from private key using libsodium?

It's not possible to directly compute the ed25519 public key from the private key. Instead, use the deterministic private key to create a seed, then use the seed to re-create the private key with its ...
skaht's user avatar
  • 3,047
5 votes
Accepted

how to convert blockchain to new version?

The issue here is with: (block.nVersion < 3 && nHeight >= consensusParams.BIP66Height) Your block has version 2, but I assume the block you are trying to download is higher than ...
meshcollider's user avatar
  • 11.8k
4 votes
Accepted

Why doesn't changing MAX_MONEY change the maximum number of coins?

Despite the name, the MAX_MONEY constant is not used in determining the total maximum number of coins. Rather, it is used only for a sanity check: any transaction output larger than MAX_MONEY is ...
Nate Eldredge's user avatar
4 votes

How to prevent ASIC mining for my new altcoin?

Are there any steps which I should include in my altcoin's mining algorithm to prevent ASIC mining? That's not really what you should be asking. You should be asking, "Can someone design an ASIC ...
Nick ODell's user avatar
  • 29.3k
4 votes
Accepted

Where can I learn how to create my own blockchain with a new transaction scheme?

The reason why you are not finding many detailed resources about blockchain is because it is a new innovation and not widely understood. Most resources are scattered across blogs and code repositories....
venzen's user avatar
  • 609
4 votes
Accepted

How to create a new genesis block using CreateGenesisBlock() function

The genesis block still must meet the proof of work requirements that other blocks must also meet. So you must actually mine the genesis block. To do this, you need to put CreateGenesisBlock in a ...
Andrew Chow's user avatar
  • 68.5k
3 votes

Bitcoin without mining - what needs to be implemented

Background What bitcoin does is maintaining a distributed ledger in which transactions are stored. Simplified, you will get a huge table like this: From | To | Amount ------+--------+---------...
Stijn de Witt's user avatar
3 votes
Accepted

Is it possible for an individual to start their own blockchain working with Bitcoin Core?

It is indeed possible, with some tweaks in the code to differentiate from the original. Effectively, you'd be starting an altcoin with all the same parameters as bitcoin. However, if it had ...
JollyMort's user avatar
  • 401
3 votes

Which cryptocurrency has the smallest block time?

EOS has blocks that are published every ~500ms, so around two blocks per second. That's a contender for the top spot for sure
rezadru's user avatar
  • 31
3 votes

What precisely are vSeeds "seednodes", how to they work, how to create one for a new network?

Couple of points covering what it is and how it works: The description might be out of date. You'd need to follow the code to see how seeding is done. E.g. IRC seeding is not used any more (but ...
Louis's user avatar
  • 126
3 votes

Tezos vs Decred

Decred is limited in what you can amend with on-chain governance. With Tezos you can amend any part of the protocol, including the governance mechanism itself.
Corey's user avatar
  • 131
3 votes
Accepted

New params of chainparams.cpp. What put on them and how generate?

uint256S("00000fffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"); //what this do ? end what put to here The first line describes a minimum difficulty. consensus....
Nick ODell's user avatar
  • 29.3k
3 votes

Is it possible to have a cryptocurrency based on email address?

With Bitcoin and its derivatives, you can already generate a private key any way you like and import it using the importprivkey RPC command. You may start with any 256 bits of data (i.e. any number ...
Nate Eldredge's user avatar
2 votes
Accepted

Problem In Creating Genesis Block Twister-Core using Ubuntu and (Qt Creator IDE)

chainparams.cpp contains a line of code that checks whether the chain’s genesis block is equal to a specified hash. Since you created a new genesis block, you will have to update the value to your own ...
Murch's user avatar
  • 72.7k
2 votes
Accepted

In what scenarios can the blockchain size decrease for bitcoin?

It looks like this part of the code is what was adding all those UpdateTip messages: https://github.com/bitcoin/bitcoin/blob/8fe30fb4d130532d4a0e4c9d143f03e1b85a749e/src/main.cpp#L2234 Essentially, ...
Jimmy Song's user avatar
  • 7,749
2 votes

Can a blockchain be created that forgets transactions whose outputs have been spent?

This is not possible with current blocks and transactions, although future improvements may allow us to prune some space from future blocks and transactions. Let's think through the idea of deleting ...
David A. Harding's user avatar
2 votes

How are some coins premined?

There are various ways to premine coins, some are use for scam coins and others are used by experimental altcoins. The premining made by scam coins are usually made with 3 methods: 1-At the first ...
kolima's user avatar
  • 21
2 votes

What is needed to get listed on a currency exchange website?

The public to whom you've addressed your question won't provide the best answer. Yours is a question about a particular business (digital currency exchanges) and so it is best directed to the few ...
Dave Scotese's user avatar
2 votes
Accepted

How to build my own bitcoin system?

Because Bitcoin is open source, the source code is the software for creating new crypto coins. Depending on what you want out of a new coin, and why you want it, the things you modify will be ...
Jestin's user avatar
  • 8,822
2 votes

How to generate Ed25519 public key from private key using libsodium?

On libsodium > 1.0.15, the crypto_scalarmult_ed25519_base() can do this.
Frank Denis's user avatar
2 votes

What are some open source blockchain projects?

The most famous open source Blockchains are Bitcoin Blockchain and HyperLedger Blockchain.
Farghaly's user avatar
  • 883
2 votes

Is it possible for an individual to start their own blockchain working with Bitcoin Core?

If you mean downloading The Bitcoin blockchain, as shared by all Bitcoin users: then yes, that's what Bitcoin Core does automatically when you start it: download all the necessary data and reconstruct ...
Jannes's user avatar
  • 6,324
2 votes

How to setup seed node?

I have been in the same boat since last 2 weeks. Made a BTC clone out of a very old source code found online. I have been a bit successful as well. All the below assumes that you are running Ubuntu....
mtaram's user avatar
  • 21

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