Homework on Consensus - Questions

[Devin.Crypto]

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

Let’s look at the term consensus as multiple accountants working together to verify if a company’s spending checks out. When the accountants are monitoring the network to see if the company’s bills are adding up. The accounts find something that’s false so they discard it. When they all find that it adds up then the accounts have completed their job and reached consensus.

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

We can look at a central database as a single accountant. His job is to manage truth in his companies tax returns. If the accountant puts the wrong number in and submits it then he failed and made it not true.

[InfinitySpark]

Consensus determines the truth because it is through a verifiable network of immutable nodes.

A central data base is easily changed, manipulated, altered, hacked, corrupted. Hasn’t worked out too well.

[Antangus]

Benefits of Using Blockchain

Q1. What does it mean when we say that in blockchain, consensus determines the truth?

Answer 1. Consensus does not rely on truth, Verification of all parties is the fact.

Q2. How is this different from how truth is determined in a central database?

Answer 2. Can not be manipulated and information must be verified.

[nitahoward]

1. What does it mean when we say that in blockchain, consensus determines the truth?
   Collectively by numerous computers and in a trust-less manner, the validation of a transaction/value is agreed upon.

2. How is this different from how truth is determined in a central database?
   A central database uses a central organization or an entity as opposed to a decision being made collectively by different parties on a network.

[Aleksander]

1. Consensus is a full agreement between all parties in network. So all computers are confirming the truth in each event.

2. Central databases belong to 1 party under 1 authority so it is under lobbing influence.

[crwnchakra]

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

Consensus allows several parties involved to anonymously decide on a transaction. Everyone in consensus comes to an agreement if said transaction is valid or not.

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

In a central database it is heavily relied on trust or what is determined to be true by authoritative figures. With Consensus it is difficult to cheat or claim something has happened if it is not congruent with data in the blockchain.

[TheMandalorian]

1. Consensus ensures that new transactions are legitimate and comply with the rules of a network.

2. In a central database the truth is defined soleley by the its owner/provider. All data can be edited or deleted anytime.

[Simenv]

1. The truth is the version of events that the most nodes agree upon.

2. The truth in a central database is whatever the owner/admin of the database says it is.

[leppflops]

1. Consensus is fundamental to the blockchain as the nodes which contribute to validating information/transactions have to reach a consensus on its truthfulness. They are incentivized for being honest (and punished for being dishonest) so they are motivated to point out transactions which are not authentic.

2. In a central database, the central authority that is the database has to be trusted that the data is genuine. There is no consensus and full trust in the database entity is assumed. If the data has been tampered with, that then becomes the (corrupted) truth.

[yoeby]

1. Since all nodes have a say on what and what isn’t true, and are incentivized to say the truth, we can verify the integrity of a transaction by listening to the majority of the nodes in the network
2. A central source dictates whether it is true or not, completely independent of anyone outside the central group

[kmony]

1. What does it mean when we say that in blockchain, consensus determine the truth?
   Multiple nodes are there to validate and determine the same truth/result. These nodes are incentivized financially to be honest.

2. How is this different from how truth is determined in a central database?
   Third party is there to verify the truth so you must trust that they will have integrity in verifying.

[IanC]

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

By using many nodes to add a transaction to a blockchain, the majority of the nodes that show the same details of a transaction will be taken.
This means that if a node has a different value for a particular transaction, it will not add added, and that node will lose the incentive for that piece of work.
So by incentivizing the adding of a transaction to the blockchain, it is in every ones best interests to add the correct transaction and not cheat.
This works as long as the distribution of the nodes is such that one group does not control more than 51% of them.

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

There is only one instance of each transaction in a single database, so the admin of the database decides the truth.

[mtylor1024]

Consensus determines the truth in blockchain because all nodes verify and agree on the input, and reject false input. Everyone is incentivized to be honest, so if there is a bad actor they will almost certainly be rejected.

In a central database truth can be determined, and changed, by whoever has control over it.

[patricia2157]

1. Becos in consensus, all decisions at all times are being made together and all united to play by the rules. So the necessity for trust is removed.
2. In central database, there may be too many variables and participants or suppliers with different agendas or imperfect work environments so errors or misinformations might arise. This system needs trust. The consensus system is built on top of financial incentives where everyone is united to one end purpose.

[Jozef]

1. Consensus determines the truth means that if decision is made on blockchain you know that several parties were involved, every PC have the copy of public ledger and and if new transaction come in blockchain they decide if it makes sense or not = not one authority decide about the truth, but all decisions in blockchain were double checked, confirmed = consensus.
2. Truth in central datrabase is determined by one regulator, authority, person, institution where we can just trust they confirm the truth and could be cheated. Instead of blockchain where everybody is confident not because of trust but because the fact, they can verify everything. Consensus is removing trust and minimalize cheating. People gain money by being honest.

[Sarmeee]

1. Consensus is centered around team work which is incentivized financially. The financial incentives of playing by the rules leads to truth.

2. The truth is determined mathematically, out of trustlesness but in central databases, the central authority intervenes to determine truth.

[Amid]

1. All parties in the network of blockchain acting as nodes confirm and validate truthful information and get incentivized for it. This motivation allows them to pick transaction which is not valid. This integrity and consensus in making a decision lead to the determination of truth.

2.In a central database, a central regulator, trustee, or guarantor acts as a third party to verify the genuine transactions. This is always subject to manipulation.

[perdi07]

1. The network is verifying the truth of the transaction / record detmining if the information sent / requested is factual.
2. As nothing can be taken away from the blockchain the information verified by the network must be accurate or available(funds). its verified by the consensus not only an individual.

[RobyRomero]

1. Consensus means that all computers in a system must agree on a transaction. If the transaction is not approved by all computers in the system the transaction will be ignored. If all computers agree with the transaction it will go through. All computers have incentive to tell the truth.

2. This differs from a centralized database because their is no trust needed to verify a transaction with blockchain. Every transaction is tracked and traced and cannot be erased or manipulated. With a Centralized database, the central authority can change or manipulate transaction that they have access to, also you have to rely that they are telling the truth about every transaction in a centralized database. With blockchain every transaction is public and you can verify every transaction in real time. There is no need for trust with blockchain.

[Alex2]

1. What does it mean when we say that in blockchain, consensus determine the truth?
   The supply chain needs to be verified by several sources so it is impossible to cheat, hnece consensus verifies the truth
2. How is this different from how truth is determined in a central database?
   in a central database either one firm or person says what is the truth or not and it cannot be verified.