Homework on Consensus - Questions

Blockchain and Bitcoin 101
#4600

  1. Consensus determines the truth by multiply nodes verifying a transaction on the blockchain, this makes sure that the transaction makes sense before it is added to the blockchain. And is not determined by a single entity therefore making it decentralized.

  2. Truth is determined on a central database purely by trust of a single entity. The creator and editor of the database.

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#4601

  1. Consensus in blockchain is trustless, agreed through a large community validators verifying the transaction, hence reaching a consensus.

  2. Decentralised, not governed by entities and/or authorities. Groups/single person can alter/falsify the data in the central database for personal gain/profit, but in blockchain, everyone are incentivised to validate the truth and no reason not to.

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#4602

  1. If a majority of computers agree or validate a transaction, then there is consensus that the transaction is truthful.

  2. In a central database, truth is determined by the owner of the database. Just how truthful the owner is, is based on trust.

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#4603

1. What does it mean when we say that in blockchain, consensus determines the truth?
That means that it is the operation has been validated by the whole network. So nobody can lie otherwise the lier will be rejected by the network.
2. How is this different from how truth is determined in a central database?
In a centralised database, the truth is also centralised by only one person. This person can lie and is not incentivised to say the truth. There is no concensus mechanism that incentivises and forces to say the truth.

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#4604

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

A blockchain based system is decentralized, verification of several computers/Nodes/network agree to add the correct transaction to the ledger/blockchain.

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

A central database is placing trust for accurate transaction information being kept on a singular database system. Consensus is not available in a central database.

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#4605
  1. Consensus is the independent verification that happens across the network and agrees whether a transaction is true and valid within the blockchain.
  2. Within a central database truth is determined by a central/single entity. Data without multiple verification points can become compromised or manipulated.
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#4606

  1. What does it mean when we say that in blockchain, consensus determine the truth?
    In blockchain each actor will read their own copy of the block chain and confirm or deny a transaction. If all actors are validating the transaction, the truth has been determined by consensus.

  2. How is this different from how truth is determined in a central database?
    In a centralized database, one single entity determines the truth. For example, if I am checking the score of a basketball game on ESPN, then the ESPN database and that database only determines the “truth” of the game score and time elapsed. There is no consensus, like if ESPN had a glitch which provided the incorrect score, it would not verify the data with NBA, BleacherReport, etc.

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#4607
  1. Consensus determines truth because data needs to be verified through consensus. Something is true if everyone on the blockchain agrees that it is true.
  2. Blockchain / consensus is different from a central database because the information is not verified by other parties. In a central database, someone might lie in order to make a profit.
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#4608

  1. What does it mean when we say that in blockchain, consensus determines the truth?
    when >50% of decentralized global network of nodes agree on the data, that data is considered true

  2. How is this different from how truth is determined in a central database?
    truth is whatever the database owner/admin says it is, there is no consensus agreement among multiple parties necessary

2 Likes
#4609

  1. What does it mean when we say that in blockchain, consensus determines the truth?
    -The nodes of the network are financially incentivized to determine what transactions are true and which are not.

  2. How is this different from how truth is determined in a central database?
    -In a central database one party gets to determine what is “true” whereas a decentralized network involves multiple parties.

1 Like
#4610

  1. What does it mean when we say that in blockchain, consensus determines the truth?
    Multiple ledgers are verifying the transaction is indeed legitimate. Because of this consensus we can say that the information is true.

  2. How is this different from how truth is determined in a central database?
    Like its name suggests, a central database has a central ledger. It does not use multiple ledgers to confirm truths. It is therefore easy for the information in this centralized database to be untruthful as there is no consensus.

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#4611

1)Consensus means that all paths have been checked by multiple systems and all have agreed that it is correct.
2)In a centralized system there is one database and whatever is on that database is “correct”

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#4612
  1. What does it mean when we say that in blockchain, consensus determine the truth?
    This means that the different parties involved( ledger holders) have agreed that one particular information is true. And this is the only way information is verified in a blockchain.
  2. How is this different from how truth is determined in a central database?
    Main difference is that in a central database you have only one ledger holder deciding what is the truth.
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#4613

1: it means that the transaction is checked by multiple systems and verified. So no Lies

2: you only have 1 “system” to determind if the transaction is true. And then you need to trust they dont lie.

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#4614
  1. What does it mean when we say that in blockchain, consensus determines the truth?
    Because we have a whole network in which every player has to agree and validate transactions turning them into truth and at the same time avoiding errors and fraud, this is possible because everyone that plays by the rules get monetary insentives in return
  2. How is this different from how truth is determined in a central database?
    in a centralized database, only the owner has access to it and he decides what is the true and what is not (if data was changed at some point in the past even aun audit would be pointless)
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#4615
  1. What does it mean when we say that in blockchain, consensus determines the truth?
    This means that the entire process in the blockchain is verified by a lot of computers. They all have to come to a consensus and when they do, this determines whether the information is true or false.
  2. How is this different from how truth is determined in a central database?
    With a central database the persons who have acces to the database determine if information is true or not. They can have the wrong incentive and can say that false information is actually true.
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#4616

  1. In Blockchain, consensus determines the truth means that the data or claims presented to us and added in the public ledger of the blockchain have been verified by economically incentivized computers that are part of a network and are incentivized, to tell the truth. This eliminates the need of trusting a party’s words about something being true or not about their product or transactions.

  2. In a central database you have one central party or individual claiming what the truth is and if it is internally within a company then it is easier to determine if the individual says the truth. If it is externally a lot more work is required and it is not always possible to determine the whole truth.

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#4617

What does it mean when we say that in blockchain, consensus determine the truth?
For a data to be added onto the block chain, it has to be agreed by the other parties verifying the data. Hence when the majority agree to the data, then it is accepted as the truth.

How is this different from how truth is determined in a central database?
In a central database, the controller of the central database determine what is accepted as truth. The controller may or may not be incentivized to accept the truth.

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#4618

  1. When we say that consensus determines the truth in blockchain, it means that the majority of computers (i.e. nodes) on a blockchain network must be in agreement as to the validity of a certain transaction or piece of information. Each computer verifies its own copy of the blockchain in order to make sure that the transaction in question can actually be made. If a majority of the computers on the network confirm that the transaction is accurate (i.e. follows on from previous transactions on the blockchain), then positive consensus has been reached and the transaction will be confirmed. However, if the majority of computers find that the transaction in question is not plausible (e.g. because the user sending a certain amount of bitcoin has never actually received that amount of bitcoin), then negative consensus has been reached and the transaction is therefore invalidated (i.e. not processed or entered into the database).

  2. This is different from how truth is determined in a central database because the users of a central database must trust those who are in control of the database. Furthermore, given that a centralised database is controlled by a centralised institution, company (or perhaps even a single individual), users of the database cannot maintain separate copies of the said database so as to verify transactions. And, even they could, the centralised database would supersede their own copy.

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#4619
  1. What does it mean when we say that in blockchain, consensus determine the truth?

It means that a network needs to agree on what is true or not true, all decisions are made together before it is added on to the blockchain

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

A central database is controlled by one party deciding on what is put in to it, making it easy to modify information to whatever they determine is the truth without anyone elses veification

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