24

In Nextcoin, proof of stake is used. So the "mining" process there is just about holding coins and leaving your computer on. It doesn't involve powerful CPUs. Each block (every 60 seconds), a random Nextcoin is selected to be the next "miner". There are 1 billion coins so the odds of a single wallet being selected is the number of Nxt in that wallet ...


21

Proof of stake is a proposed alternative to proof of work designed to increase network security. It's not currently implemented in the main chain (and would likely require a hard fork to implement), but alt currency PPCoin features a hybrid proof-of-stake/proof-of-work system of sorts. With proof of work, the likelihood of mining a block is dependent on the ...


13

Vanilla proof-of-stake doesn't achieve consensus, unfortunately. People staking their coin can vote for both forks of the blockchain, and can even mine effortlessly in secret. In PoW this is impossible, as you are literally wasting energy by mining both sides of a fork. To mitigate this, most modern PoS schemes use a mixture of PoS and PoW to ensure that ...


13

Proof-of-stake mining is similar to Proof-of-work at a technical level. It involves a sort of lottery, similar to proof-of-work, but the difficult of this lottery is weighted depending on how many coins you are staking. The overall process for "attempting" to mine a PoS block is like so: Add a coinbase transaction, and a staking transaction (in most coins, ...


10

I don't know of any such list yet, but no reason we can't start making one. :) Others should feel free to add their findings via an edit. Proof of Work Proof of Stake Proof of Activity Proof of Storage Proof of Knowledge Proof of Stake Velocity Proof of Burn Dual Purpose Proof of Work (Primecoin) Proof of Lock (Tendermint) Delegated Proof of Stake (...


9

For Peercoin specifically, PoW and PoS blocks are independent. Just as you're betting your consumed electricity and CPU-time vs. the possible PoW-blok's reward, in the PoS blocks you're betting your coin-age: the amount oF PPC you own multiplied by the number of days they've sitted idly at your wallet. It must be a minimum of 30 and a maximum of 90 days for ...


7

Proof of burn simply means you have provably destroyed coins. The only way to destroy coins in a proven way is to send them to an address which is improbable to have been generated from a private key, and thus can not be spent. Chancecoin is the first I've seen to use this way to generate their coins. The announcement for Chancecoin can be found here: https:...


7

Attention: Ambiguity! Note that the term (or abbreviation) "PoB" can be used differently. For example, some cryptocurrencies allow users to get some of their coins for provably burning money in Bitcoin, essentially deriving their values from Bitcoin's value by deriving their scarcities from Bitcoin's scarcity. Yeah, but what about my question? The idea ...


6

A really quick answer is this: The proof of work system is a solution to the distributed synchronization issue; in another guise it is called the Byzantine Generals' Problem. Thus, any solution to this problem is an acceptable alternative, however the proof-of-work solution is particularly suited to distributed systems. You can read Satoshi Nakamoto's ...


6

The following points try to simplify/abstract: A cryptocurrency has its own blockchain to store all the transactions that occurred. A proof of work/stake algorithm are different methods (or algorithms) to achieve consensus on which block will be added next to the blockchain Proof of work (PoW) requires proof that work of some kind occurred. In the case of ...


5

Another alternative is proof of burn.


5

Even if the dynamics are interpreted in the most basic way, it does not lead to this positive feedback, rather it maintains the status quo. If there are miners with stake of 40%, 30% and 30%, they will get 40%, 30% and 30% of the rewards respectively, so the ratios will remain at 40%, 30%, 30%. For example, if they start with 40, 30, 30 BTC, and 10 new ...


5

Essentially, PoS' nothing at stake problem is that you don't lose anything by mining. In Bitcoin, you lose the money you spent on energy to power your miners. Thus, in bitcoin mining you want to make sure you are mining on the correct chain all the time so that you have the best possible chance of your solved block being accepted by the network. In PoS coins,...


5

If it is a web wallet that holds your private keys, then it is certainly possible that the service is staking your coins for you, but this may or may not be a feature that the developers of the particular web wallet have implemented. It is also possible that the web wallet creators take the stake as a payment for their service, which I hope the service would ...


5

Calling Lightning a Proof-of-Stake system is orthogonal to the concept usually labeled as PoS. Him having done so will just generate loads of confusion. What we usually describe as PoS is a mechanism to achieve distributed consensus among a network of participants. Staking there is providing updates to the whole network's state, where you earn fees for ...


5

The Ardor launch will happen in 2017, but the distribution of the main ARDR tokens will be based on the Nxt 1.0 balances. And yes, as far as I know it is the first scalable blockchain platform using 100% proof of stake. Starting the next 14th of July, the Nxt network will take a snapshot of all the account balances every hour. This will last for three ...


5

Decred has a hybrid Proof-of-Work/Proof-of-Stake model, which means that block rewards are shared between the miners and the stakers (and the developers), with PoW mining earning the larger portion of the reward. (60% PoW miners, 30% PoS voters, 10% Decred development subsidy) The way staking works in Decred is through a ticket system. You purchase a ticket,...


5

The minting algorithm for staking is different for various coins; for example, it is different in BlackCoin from Cardano. There are several approaches to staking, but most of them are susceptible to "grinding attacks" and almost none of them are proven secure against every attack (only argued secure intuitively by showing that certain specific attacks do ...


5

I think you might already know the answer, based on your question. The "chain of blocks" has value in Bitcoin because of the proof of work. It is also provides a data structure that can be used in an efficient way to verify the integrity of the chain, but that is not really what makes it interesting. A permissioned blockchain, obviously, requires ...


4

Arguments of Nxt creator are written here - https://nxtforum.org/initial-distribution/initial-distribution-of-100-pos-currencies/: Initial distribution of the coins and the forging schedule are more serious problems than they appear at first glance. A 100% proof-of-stake currency needs at least a small part of the coins to be distributed in the ...


4

Proof of stake has been used for many months in Nxt, and has not been broken despite having the third highest market capitalisation, so it does seem to be secure. If it wasn't, someone would have broken it by now. History shows forks rarely persist for more than a block, so it does achieve consensus. In theory, a weakness is that people can vote for both ...


4

The general problems you are describing are inherent flaws in PoS, but you've caught onto some of the basic principles that are going to impact the security and integrity of the cryptosystem. Anyway, even if we can't roll back in time, could we edit the program to try as many hashes as possible every second. For example, suppose we try 100 times to hash ...


4

This problem is generally known as "nothing at stake" or "costless simulation", where there is indeed nothing preventing anybody from making arbitrarily long chains where they are the only participants in the network. If you were an early majority holder of the altcoin, emulating a massive network with thousands of users and then presenting that to peers ...


4

Can the same miner / address / person be chosen to create multiple blocks in a row Yes, a single entity can mine multiple blocks in a row with no ill effect. are there some mechanisms preventing [multiple blocks in a row from one entity] from happening? The sybil problem makes this fundamentally impossible; if there was a way to stop a person from ...


4

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 bit of a simplification, (Ethereum has other improvements like GHOST) but for our purposes (discussing how a Turing complete scripting language could be ...


4

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 there will be basically a timeout; if a fork is detected during that timeout, the signer that created the fork loses his money. But after the timeout, he does not....


4

The Ouroboros line of work proves security comparable to Bitcoin's security. The proofs of security in Ouroboros are similar in style to the Backbone proofs of security, which show that Bitcoin is secure. To my knowledge, there are no alternative proofs of security for Bitcoin which are formal - these are the best results we know of that illustrate that ...


3

Yes, you have to have client with all your coins open with your private keys and have it sitting on online machine. See Proof Of Stake Details section for NXT


3

You can't do this due to the Sybil Problem. There is no way of proving a node is an individual participant in the system, you can't prove that a node existed at any point in time (or didn't), and there's no source of random numbers at all in the system which can't be influenced or altered. Proof of Work is a side step to having potentially clones ...


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