Homework on Consensus - Questions

  1. the truth is found as the search for false is weeded out. Together and agreement is made as to wether a transaction is true or false.

  2. in a centralized database the truth can be misleading and incapable of being verified without centralized oversight. And even then the truth can be hidden or misdirected, unlike open verification through the blockchain.

  1. It means everybody in the public ledger will check and confirm if the transaction makes sense. And as every one is incentivized by confirming the truth there will be no chance to for false transactions.

  2. Its trust less !

  1. What does it mean when we say that in Blockchain, consensus determine the truth?

The network will agree that a transaction is valid, not one entity.

  1. How is this different from how truth is determined in a central database?

A central data base is owned by one entity and can be changed and manipulated.

  1. all nodes verify each transaction across the network.
    consensus of information among participants in a network achieved in a decentralized trust less way.

  2. Traditional methods require a single authority have control of all information.

Homework on Consensus - Answers

What does it mean when we say that in blockchain, consensus determine the truth?

  1. The decentralized miners are financially incentivized to be honest by confirming
    the accuracy of a transaction and disallowing inacurrate transactions. This process
    allows for and supports the consensus model providing truth and transparency.

How is this different from how truth is determined in a central database?

  1. A centralized database relies on data that can be manipulated intentionally or inadvertently by anyone having access to the data. To rely on the data trust and auditing is necessary and still it may be corrupt.
  1. Consensus determine truth in that no element of “disagreement” among nodes can be accepted thus whatever remains is generally agreed as “truth”

  2. Traditional database is just self-opinionated judgement- lacking in agreements from all players.

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Homework on Consensus - Questions

1. What does it mean when we say that in blockchain, consensus determine the truth?
The blockchain network consists of a decentralized network of nodes which act independently of one another. Each blockchain node is required to validate the authenticity of the new transaction before this new transaction is allowed to update the blockchain’s ledger.

Once ALL blockchain nodes reach a consensus (are in agreement) that the new transaction is validate the blockchain ledger is updated and published to all decentralized nodes connected to the blockchain network.

Each new blockchain transaction is independently double checked and verified by ALL nodes within the decentralized network leading to a global consensus the new transaction was valid and accurate eliminating the need to trust the individual instigating the new transaction.

2. How is this different from how truth is determined in a central database?
Global consensus by ALL nodes removes the need to trust a centralized database to validate the accuracy of the new transaction.

Rather than relying on a centralized database to make a decision all blockchain nodes (parties) must reach a consensus leading to a trust less system because the transaction was independently verified by ALL, and not verified by a single or centralized database which could be tricked into considering the new blockchain transaction was valid.

  1. When network of decentralized nodes (more than 51%) come to an agreement that transaction in blockchain occurred, the consensus is reached, and this transaction becomes immutable part of the block.

  2. In central database ”the truth” is often determined by those who have power to modify it.

  1. Consensus is the process in which the participants of a blockchain reach agreement about the truth.
  2. In a central database truth is determined by a single entity.
  1. Consensus is a agreed upon truth about everything that’s put into a transaction is factual

  2. Because you have to rely on whoever is inputting information on a central database is telling the truth or just fabricating something that sounds good

  1. In the blockchain, the network makes a verification of the data with each copy. This can lead to a consensus building a chain of truth.
    One mistake can breaks the process and so the network without consensus proves it is no the truth
  2. In a central database, we can replace it or an authority can change everything or data can be deleted. So truth in these database relies on the confidence in the authority
  1. What does it mean when we say that in blockchain, consensus determine the truth?
    When consensus is achieve, every node in the network update their copy of the blockchain with the new data. If one of the nodes decides to update the data differently than the others, this node is kicked out of the network.

  2. How is this different from how truth is determined in a central database?
    The consensus in a centralized data base is determined by only one participant. On a blockchain the consensus is determined by nodes in different countries, having different interests, langages, religions, etc. But all nodes have the incentive to be honest to their peers, otherwise they will be kicked out.

  1. What does it mean when we say that in blockchain, consensus determine the truth?
    All computers that keep a copy of the blockchain are in communication in order to verify validity or truth of an event/action.

  2. How is this different from how truth is determined in a central database?
    In this case, information is compared to what is stored in the database. It is centralized and therefore managed by a limited number of entities.

  1. It means the network confirmed the data.
  2. In a central database you just have to take their word for it.
  1. Individual ledgers verifies the transaction/data so it’s valid.
  2. Widely trusted institute usually offers the database therefore you are required to trust this entity.

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I am using a pristine commercial internet connection and they still stop every so often to load.

  1. When there is consensus in a network of nodes, it basically means what the majority of the nodes agree on is the truth. This means that when more than 50 % of the nodes say that X is true, then the network has achieved consensus on X being true, meaning that X being true will be stored in the next block in the blockchain, e.g.

  2. In a centralized network / database, there is no need for consensus, since the authority maintaining the database determines what’s true and what’s false. In a decentralized network / database, no single authority can determine what’s true and what’s false, since (when that single authority is trying to say that X is true) the rest of the nodes / network will say that the authority is wrong.

All nodes have to agree that a transaction is valid - this consensus determines what is true.
A central database has a record updated by a single party (perhaps subject to veriification) - there is no requirement for multiple parties to agree on the entry.

1 O consenso determina a verdade pois é um processo que não evolve confiança e sim um mecanismo isento de parcialidade que funciona através de incentivo financeiro (mineração), garantindo a confiabilidade

2 Em uma base de dados centralizada não existe confiabilidade, pois os incentivos para deturpar os dados são em muitas vezes maiores do que os incentivos para manter a integridade das informações e dados.

  1. It means the majority decision of a group of participants is the truth. The participants are incented to tell the truth and those who do not tell the truth will pay a financial penalty.

  2. In a central database, the owner of the database decides what the truth is. There is no consensus since there is only one decision maker. A central database required trust.