2.In a central database truth can be determined by one central actor. and if that actor is bad acting on behalf of wrong doing than that is bad for the rest of the database.
In a blockchain, every nodes needs to agree that the transaction is true, then the consensus becomes true.
In a blockchain, the truth is determined by all nodes while in a central database, the managing party determines the truth. We need to trust the managing party of the database while in blockchain, there is no trust needed, only verification.
In blockchain consensus determines the truth means that enough people or nodes, or enough transactional value determines the truth and is enough because it is mathematically provable to be true.
Truth is different in blockchain than a central database because all every part of the database is incentivized to provide truthful information. For example, through mining to reward computers or people to verify transactions.
That means that all the computers (nodes) in the network are incentivised to tell the truth. Because they get awarded for truth. And because there is such a high number of nodes, it is impossible that majority would confirm the same lie. Consensus that is made (confirmed from all) is the truth.
In central database truth is determined with trust. Trust that central authority would be honest and fair and would not corrupt any data. Data is accepted without consensus of many parties.
The single participants in the information network are incentivized to be honest and to check the trustworthyness of data and reveale false data by not confirming them. Only by getting the consensus of the network a new set of data will be added to the ledger.
In a central database an authority decides the truth and can alter datasets or accept them as true arbitrarily.
Homework on Consensus - Questions
1. What does it mean when we say that in blockchain, consensus determine the truth?
The people works collaboratively to reaffirm a transaction because of economic incentives
2. How is this different from how truth is determined in a central database?
In a central database there is an authority. Might not be truthful and can alter the database.
Anyone can verify a transaction.
There are multiple verifications with block chain.
What does it mean when we say that in blockchain, consensus determine the truth?
An agreement between multiple entities determines truth.
How is this different from how truth is determined in a central database?
One party is solely responsible for the truth.
Hey Ivan,
1.-if we had a closed network with the same transaction history and ledger, everything must look like an absolut truth to them, lets say like a small amazon community, not just the leader knows but everyone does.
2.-Just because the teacher says 2+2=5 that should be truth if and when every student has the same book to verify thats not ok and to correct the teacher
1. What does it mean when we say that in blockchain, consensus determine the truth?
Multiple computers on the network verify transactions, thus determining the truth.
2. How is this different from how truth is determined in a central database?
In s central database, the truth is whatever whoever is in charge of the database says.
1.If for example a new transaction wants to join the bc, many different computers check the whole bc, if the transaction is possible. When all the computers agree, they are in consensus ans the transaction will be added to the bc
2.In a normal database only one entety approves the truth of the data, so it is way easier to cheat
1.Consensus determines the truth by using a network of participants who are incentivised to tell the truth, telling the truth.
2. With a central database we take the word of and have to trust a single entity who can be a bad actor in a given scenario. So again trust is needed.
- What does it mean when we say that in blockchain, consensus determine the truth?
Nodes are economically incentivized (securing the network) to determine whether the transactions are true or not in a decentralized way.- How is this different from how truth is determined in a central database?
Its a collective agreement with no central authority.
Consensus is the agreement of a collective rather than an individual which removes the need for trust. Nodes are incentivised to be honest.
Central databases can be controlled by individuals. Therefore anomalies can occur.
The consensus mechanism of a blockchain gives every participant an incentive to be honest. They will make money by playing by the rules, because a dishonest transaction will be disproven by all other participants. If they try to be dishonest, they will not make money or even lose it (i.e. the cost of electricity).
We rely on the honesty of the central authority of the database.
In a blockchain, consensus determines the truth because it removes trust, as all transactions need to be agreed upon before they are included in the blockchain. In the bitcoin blockchain, consensus is reached by incentives. If you play by the rules there is an incentive, you will earn money, if you don’t you will loose money.
A central database is centralized, there is no need for agreement or consensus therefore you will need to trust that it is not going to be manipulated.
Because every computer has a copy of all information stored inside the blockchain, a single individual can´t lie and try to inject a wrong information into the blockchain, as every other computer will prove the information wrong.
In a central database the central identity chooses what is true and what is wrong.
*Question: what if someone somehow got access to lets say half of the network can this person inject wrong information in a blockchain?