Homework on Consensus - Questions

Blockchain and Bitcoin 101
#5808

  1. the truth is determined by all the nodes coming to a consensus where there cant be another version of the truth to be be in a block

  2. a central database truth can always be changed depending on who owns it or who is given authority to change the data.

1 Like
#5809

  1. Determining the truth through consensus on the blockchain is done when all nodes come to agreement on any particular transaction/set of transactions

  2. With centralised databased, truth can be determined and manipulated by whoever has control of the database

1 Like
#5810

  1. Nodes verifying the truth. We reach consensus through incentives.

  2. In a central database, the central authority decides the truth while in a decentralized network the nodes decide what the truth is by verification.

1 Like
#5811

1.This means that network validation prevent fraud. Multiple nodes are required to make a decision. They are incentivized to discover the truth. Network redundancy prevents accidental loss.
2. This is different as in the central database the owner can corrupt the database himself. Proof of authority is all what is required. It is difficult or impossible to independently audit.

1 Like
#5812
  1. What does it mean when we say that in blockchain, consensus determine the truth?
  • True information bases on the agreement of all participants in the BC network that this information is correct. So only if all network members agree, an information becomes true.
  1. How is this different from how truth is determined in a central database?
  • A central database is controlled by few individuals/companies, so the definition of truth can me „defined“ by the agreement of the few instead by agreement of all participants in the business.
1 Like
#5813
  1. It means that the truth is verified by a network rather then separate parties. Every part has to confirm and verify a single exchange.
  2. A central database will not be available for everyone, hence the truth can only be determined through individuals or groups that have access, which again removes us from the faculty of not having to trust.
2 Likes
#5814

  1. Because everyone validates the information and anyone trying to cheat is rapidly identified. Thus, you build the truth by your own validation.

  2. In a centralized system, you have to trust the information owner. Here, you can validate it’s true.

1 Like
#5815

1 In the say that nobody can’t cheat nobody because everybody is watching

2 That in this case it’s a mathematical system which involves no trust

1 Like
#5816
  1. What does it mean when we say that in blockchain, consensus determines the truth?

Validators on the blockchain reach an agreement that the information (blocks or transactions) are valid through a consensus algorithm (for Bitcoin SHA-256).

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

Within central databases, parties involved my trust a centralized authority for the database. Blockchains are decentralized and use a trust-less way of achieving consensus by verification without the need for centralized authorities.

1 Like
#5817
  1. What does it mean when we say that in blockchain, consensus determines the truth?

When all the computers, or the majority of computers, in the network agrees that the statment beeing put into the ledger is correct, that determines what “true” version of the ledger exist and is valid. If a compter try to cheat by making a false transaction, the other computers will reject that version of the ledger and it will be considered not true,

  1. How is this different from how truth is determined in a central database?
    In a central database, one computer decides what is true. No other computer is checking if the database transaction or if the state of teh database is as it should be. You have to TRUST that computer. You can not verify
1 Like
#5818

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

It means that every participant agreed on the idea of earning money, so in this case everybody can make consensus only if transaction is true.

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

In central database truth is strict in one places. It can be hide, unaccessble and not to be the truth at all. And participants are agreed to believe in it without strong proof.

1 Like
#5819
  1. What does it mean when we say that in blockchain, consensus determines the truth?
  • In the blockchain, the various node on the network works to make it so that it requires the nod/confirmation of all the nodes to realize the truthfulness/validity of the transaction. Thus, the word “consensus determines the truth”.
  1. How is this different from how truth is determined in a central database?
  • The decision for the validity of the data is in the hands of the authority holding the ownership of the database. If the owner deems it true, even the false data can be seen as truth.
1 Like
#5820

  1. Each nodes has agreed with the terms to verify a transaction. They will keep this concensus as they are rewarded via incentives

  2. Because a central database is based on trust and can be altered.

1 Like
#5821
  1. What does it mean when we say that in blockchain, consensus determine the truth?
    Consensus does not rely on a centralized company/person to verify data, rather a group of trustless computations to verify that transactions are true according to previously verified transactions.
  2. How is this different from how truth is determined in a central database?
    Centralized databases rely on trust to confirm data, whereas blockchain offers verification through public ledgers that all verifiers can agree upon.
1 Like
#5822

  1. Consensus determines truth because each participant can validate whether or not a transaction is true. Even if one or a few participants verify a false transaction as true, if a majority of participants disagree on that transaction then the transaction is not valid.

  2. This is different from a central database because with a central database the opposite can be true. If 1 participant holds the sole authority over whether a transaction is true/false they can make false transactions true without the validation of the majority of participants. This creates an environment that allows fraud, vulnerabilities, and unreliable data.

1 Like
#5823
  1. All members of the consensus must agree on what is true or false, and when this happens, the truth is obtained.
  2. In a central database you have to trust in whoever or whatever controls it.
1 Like
#5824

  1. All transactions in the blockchain need to be approved by the nodes in the network. The nodes are getting financial incentives to “tell” the truth. This way it is very hard to be dishonest.

  2. In a central database 1 party can change or manipulate the data stored. This way it will be very easy to be dishonest, and we all need to trust the owner of the database to be truthful.

1 Like
#5825

  1. Consensus determines truth because data is basically audited between multiple parties/datasets . Therefore the data is most likely true

  2. A central database can be manipulated and any number of truths can be manufactured.

1 Like
#5826

Consensus is the agreement of many within the network, that a transaction is valid and consequently verified instead of a single or minority being able to verify a transaction against the majority.

With a central database all information is verified (and stored) by one single entity.
If this entity is faulty, corrupted or influenced by other the outcome will be accordingly and useless. Thereby also a waste of energy (esg…. :wink:

1 Like
#5827
  1. With consensous the truth is determined by the majority, when the most thouth or answer the same, means that the information it’s valid. In big networks it’s really difficult that the majority were wrong.
  2. Central databases are bases in the trust. Being a centralised system, coulb be manipulated and the user cheated since they trust in the origin of data.
1 Like