Homework on Consensus - Questions

Blockchain and Bitcoin 101
#4420

1. What does it mean when we say that in blockchain, consensus determines the truth?
Consensus in blockchain determines the truth because the information agreed upon by the majority of the network. This works because the network is composed of several independent computer nodes that are all running their own copy of the blockchain and in communication about rules of the protocol. This creates a trustless ecosystem and makes the blockchain immutable and very hard to tamper with. This works because the miners are incentivized to keep in alignment with the rules so that they can add to the network and earn their portion of the block reward.

2. How is this different from how truth is determined in a central database?
This is different because it requires all the computer nodes in the whole network to agree upon the data and follow the same strict mathematical rules that make the network work. One computer in the blockchain cannot change the truth of the network because the rest of the nodes will reject the information and it will not be added to the blockchain. In a centralized database, the information can be changed and the truth will be altered.

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#4421

1.) In a blockchain when there is a transaction, all ledgers had to be in consensus that this is right, after that the transaction is added on the blockchain.

2.) A database is not decentralized, the person who owns it or had the control can say it is the truth or not. It is also possible that the person can cheat in this decision. So you had to trust this person.

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#4422

A1: It means that all individuals/nodes have to agree/ approve for something to be considered the truth. It is collaborative work of the network, a.k.a the whole network has to reach consensus for a motion (transaction) to go through.

A2: In a centralized database there is an authority in charge, with the possibility to override/alter information which in turn compromises the transparency and ‘the truth’ itself.

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#4423
  1. What does it mean when we say that in blockchain, consensus determines the truth?

It means that all decisions are made together by creating consensus and double checked. Several parties are involved, everyone is talking to everyone and it is difficult to cheat

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

It is different because consensus is achieved by financial incentive ei. Mining. Everyone needs to play by the same rules because only then will get the incentive.

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#4424

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

    • A network of participants work together and are rewarded for truthful and accurate data confirmations. Whereas there is no incentive or even punishment for falsification.

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

    • Lack of reward in governing supervision within conventional models naturally incentivize cheating. There is no network supervising data being added to a record and the only way to create an advantage is to find an exploit in the system.
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#4425
  1. What does it mean when we say that in blockchain, consensus determines the truth?

Multiple computers/nodes on the network validate the transaction and if it is a valid transaction multiple nodes in the network will validate the transaction. For example if party A sends 1BTC to party B then party B balance will be 1BTC and multiple nodes on the network will have confirmed this and if party B wants to send it to party C multiple nodes on the network will confirm that party B can send funds to party C.

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

A central database can be modified by the admin or delegated user so the balance could be changed and no other party can verify that it was not tampered with.

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#4426
  1. What does it mean when we say that in blockchain, consensus determines the truth?
    Networks working together with the same incentives to verify transactions are valid. This eliminates opaqueness and working off of an “honor system” by simply being able to verify, accept or deny transactions.
  2. How is this different from how truth is determined in a central database?
    Centralized databases are not real time, truth can be altered, there is little accountability, the truth can be layered and hidden, difficult to verify.
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#4427
  1. What does it mean when we say that in blockchain, consensus determines the truth?

In Blockchain, consensus is an agreement made by all the participants on the network based on the verification of a transaction. The transaction can only be added on the blockchain when all the paricipants prove it is ture.

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

A central database is centralized, it is mantained and updated by a central authority, the central authority can add, delete and manipulate the data, so the truth is detemined by the central authority. Blockchain works without any single authority and it involves thousand of participants. The truth is determind by consensus from all those participants.

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#4428
  1. What does it mean when we say that in blockchain, consensus determines the truth?
  • That all parties of a network(blockchain) have to approve/accept any new transaction going into the network.
  1. How is this different from how truth is determined in a central database?
  • A “central” database is a centralized database owned/maintained by ONE entity. This means that ONE entity alone has access to modify data in the database and you will have to “trust” this data is not modified or compromised.
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#4429
  1. What does it mean when we say that in blockchain, consensus determine the truth?

A: Takes out the trust for verification, allowing multiple parties to come together in agreement by accepting the transaction to the blockchain.

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

A: In a central database one party approves the transaction alone relying on trust vs in a decentralized database multiple parties come together and verify the transaction eliminating trust.

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#4430
  1. In blockchain that refers to the fact that multiple computers in the network are all making conclusions together, ensuring each transaction on the blockchain actually exists. With only 1 computer there can only be a conclusion, not a consensus.
  2. In a central database there is one person or entity/government controlling what the truth is.
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#4431
  1. What does it mean when we say that in blockchain, consensus determinate the truth?

In a blockchain to register one transaction the nodes have to accept it, in order to accept it, they have to reach a consensus to allow that transaction to enter into the blockchain and to reach that consensus the information has to be verified. If we have in mind that all transactions accepted in the blockchain can’t be removed or changed and anyone can access that information, all the participants in the industry or supply chain can work with each other to make the entire business more transparent.

  1. How is this different from how the truth is determinated in a central database.

In a central database the information is approved for one person or company, it doesn’t have any other person that can verify what he can register into the database. Therefore that information can be manipulated for different purposes. This procedure obligates every company to trust in what other participants say that they do, but with this procedure companies can cheat in the registration of the information.

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#4432

  1. Blockchain concensus is only achieved when validation occurs on the transaction or input of data and only then will it be added to the blockchain.

  2. Databases which are central are not created with public consensus.

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#4433

  1. Consensus in the blockchain requires a group to agree on any changes or alterations. If a fraudulent change is attempted, others with the public ledger “Blockchain” can spot the irregularity and will not allow the change in the Ledger. This group verification is what determines truth.

  2. On a central database one person or group controls the information. The ledger does not have to be public, and alterations can only be made by chosen individuals. If the individuals in charge of the ledger make a mistake or have bad intentions then now the ledger is no longer acting in a truthful fashion.

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#4434

1.) It means that all parties (nodes) on the blockchain have to agree in order to confirm a post to the ledger.

2.) In a central database there is a centralized authority who can make changes to the database. There is also no incentive for a central database to be truthful.

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#4435

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

The truth is a collective decision and can be verified by all the components that participate in that network.

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

In a central database, the truth is based on the trust of those who have control and the power to change it.

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#4436

  1. Consensus truth is determined through multiple nodes agreeing that the data input into the system is verified information. Once deemed creditable by the network the data is then accepted into the chain.

  2. Truth in a central database is subject to the authority of who ever governs said database. There does not need to be network approval. therefor the data in a centralized database can be tampered with and changed at the will of its curator.

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#4437

  1. When we say consensus determines the truth, it means that all participants are incentivized to play by the rules and so when they form a consensus, we can trust that it’s true.

  2. In a central database, anyone with the right access can add, modify, or remove data, so there’s no way to verify its accuracy.

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#4438

The accuracy of a transaction is determined by the information stored in ALL of the computers that hold the Blockchain. That consensus determines the acceptability of the transaction (information) and if it should be permanently added to the ledger. At that point it will forever be considered TRUE.

It is different in centralized systems because the company, government or the banking system etc. has the access to making changes to records that hold transactions or can conveniently “lose” data. Especially as it pertains to governments all around the world and taxation etc. That along with the many cases of human error, its no wonder the system is the way it is today.

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#4439
  1. What does it mean when we say that in blockchain, consensus determines the truth?

Consensus is the way transactions are verified on the blockchain and it is done by incentivizing the miners to always tell the truth and only write correct transactions into the Blockchain.

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

The truth of a central database is determined only by a few who govern it and can (at times) be easily tampered with and modified.

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