Homework on Consensus - Questions

Blockchain and Bitcoin 101
#5848
  1. What does it mean when we say that in blockchain, consensus determine the truth?
  • All players in the network are incentivized to “tell the truth” by validating if a transaction is correct.
  1. How is this different from how truth is determined in a central database?

  • In a central database, the entity that owns and controls the database make the call. Just like how the Facebook company decided which user to ban, or what kind of image is allowed to be posted on the platform.

  • If the entity decides to present the truth in a certain way, they can just do it.

  • But if using blockchain, such cannot be done, as you will have to get consensus from all players in the network, rather than you alone.

1 Like
#5849
  1. What does it mean when we say that in blockchain, consensus determine the truth?
  • all decisions are made by consensus of network
  • network of computers doing the math/algorithms that reach agreement (provinence verify/validate)
  • the network, incentivized, to tell the truth
  1. How is this different from how truth is determined in a central database?
  • no way to determine if there is truth in a centralized governed database
  • no transparency, no provenance
  • the truth can be manipulated
1 Like
#5850
  1. What does it mean when we say that in blockchain, consensus determine the truth?
    Ans The nodes in the network have to all agree that the transaction is true and any dishonest behaviour is punished.
  2. How is it different from how truth is determined in central databases?
    The difference is that the in a central database there is one central administrator who can corrupt the data and therefore difficult to independently audit for errors.
1 Like
#5851
  1. What does it mean when we say that in blockchain, consensus determine the truth?

The network (network of nodes) collectively decides if a transaction is valid or not. If so it gets added to the public ledger and if not it gets discarded.

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

In a central database central authority, (which can be a single person or a group of people) solitarily has controll over the network and can manipulate/ alter the truth however they please.

1 Like
#5852

  1. In blockchain concensus determines the truth by having nodes and validators agree that the current transaction/block is valid throughout a huge majority of the network. this is based off previous transaction chains which all nodes and validators have, as well as current transactions each node is processing. which makes suspicious transactions stand out compared to what the network actually has.

  2. A centralized Database has data stored in one area which requires the people interacting with the database to trust that the data point they are accesing is true. this is a weaknes as it can be manipulated and there are no other points to validate if it is factual. Where as on a Concensus mechanism this database is equally distributed among the network requiring no trust that one specific access point is accurate, but rather since ALL the data points say the same thing, provides factual proof that the data is legitimate. which can easily disprove is one specific node has data different than the large majority.

2 Likes
#5853

  1. What does it mean when we say that in blockchain, consensus determine the truth?
    Consensus uses a network of computers to determine what is true and what is untrue. The objective of Consensus is to remove central trust and by doing so it creates a trustless decentralized network - this is executed with incentives.

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

Truth in a central database defines/determines truth from a central authority as opposed to a trustless network, take how web 2.0 is structured right now where the centralized databases are controlling and censoring and in some cases removing truths. This is the complete opposite of the Blockchain where nothing can be removed.

1 Like
#5854

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

Consensus is general or unanimous agreement. In a blockchain system, the computers on the network provide consensus about the validity of a transaction. If there is consensus about the transaction, it is accepted as a part of the blockchain database, and is confirmed as valid. If there is a lack of consensus, the transaction is rejected, and not included in the database. With blockchain, more than one person / device decides about a transaction. Decentralization, combined with consensus, eliminates the need to trust a single person / device. Instead, a network of computers check, and confirm or reject, new data which someone is attempting to add to the database. They prevent incorrect transactions (for example an attempt to spend from a wallet which does not have enough crypto available to pay for the transaction).

The people who own blockchain nodes receive financial benefits, in exchange for providing well functioning computers which provide accurate consensus for transactions. This is a financial incentive, which prevents them from allowing or attempting false transactions in the database.

In addition, with public ledger blockchains, such as bitcoin, anyone can look at the blockchain’s ledger, if they have a computer and an internet connection, and personally get information about transactions on the blockchain. Such openness further eliminates the need to trust a centralized authority.

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

A person using a traditional, centralized database (which can be changed without decentralized consensus), can change the information in that database. This change of the stored data can be done without another person or device checking on the validity of the change. In such a system, belief in the correctness of data is based more on trusting the person who manages the database, though that person might lie or make mistakes. Therefore the data in such a system may be less reliable.

1 Like
#5855

  1. Consensus determine the truth In blockchain because is decentralize, everyone is incentive to tell the truth, by economics rewards.

  2. In a centralise database, you don’t have incentive (usually) and you can cheat the system, and give “yourself” a fake reward.

1 Like
#5856

  1. What does it mean when we say that in blockchain, consensus determine the truth?
    The network of computers have incentive to tell the truth and stop dodgy transactions without a biased opinion, there is no middle man.

  2. How is this different from how truth is determined in a central database?
    If the company is corrupt it can shadow the truth.

1 Like
#5857

  1. The nodes, or different computers that have access to a given ledger reflect what the collective determines as the truth. Therefore, no single node or transaction can be made without validation from all other networks that the transaction or process is genuine.

  2. In a central database, truth is pretty much determined by whichever entity controls the data. Achieving consensus is bypassed, and decision making, fact checking, and transparency can all be decided on by one source. Thus, there becomes a very real reliance on trust over the verification of truth.

1 Like
#5858
  1. Consensus uses a network of computers to determine what is true and what is not true. The objective of Consensus is to remove central trust and by doing so it creates a trustless decentralized network - this is executed with incentives.
  2. The difference is that you can not verify through consensus the content in it. A centralized database is owned by someone or a group of people and they can change what’s in it. It can also be hacked. The information has to be trusted, you can not verify it as truth
1 Like
#5859

  1. In blockchain, a network of computers collectively make decisions which allows for a trustless system. Each individual in the network is incentivised to be honest which is achieved through financial rewards.

  2. In a central database an individual is able to make changes to the system solely by themselves and can make changes to records if they choose to which will alter the truth.

1 Like
#5860

  • What does it mean when we say that in blockchain, consensus determine the truth?
    It needs a network of computers to all validate that the information received is similar to all others. The information received is checked transversely in equal manner. . As any single computer by itself is considered trust less, the validation by the entire network validates the infos in a consensus (from the Latin root:agreement)

  • How is this different from how truth is determined in a central database?
    A normal database doesn’t require a similar agreement to validate informations. Therefore informations/databases can be manipulated, erased, transformed.

1 Like
#5861

its means that people in the network agree whether a transaction is good to be added to a ledger, if the network things its fake it discards it
2. a central database can define there own truths which can corrupt because central authorities decied the truth

1 Like
#5862

  1. When a consensus is reached in the blockchain, it is through verification by all parties to determine the truth, thus removing the trust in the process because we understand that everyone can verify and agree that the proposer is legitimate and being honest through the mechanism of the blockchain or ledger so to speak.

  2. In a central database, the proposer is also the party to verify and agree, which creates biases in the first place. The only way to determine the truth is through another party, which works in a similar fashion where the others have to ‘trust’ but not necessarily verify. Thus this presents a loophole where too much trust has to be built-in into a centralised system as the processes become more complex.

1 Like
#5863

  1. What does it mean when we say that in blockchain, consensus determines the truth?
    A majority of network participants agree to accept new ledger entries from other participants

  2. How is this different from how truth is determined in a central database?
    A single (non-majority) entity can determine was to reject/accept

1 Like
#5864

  1. When a decision is made, several parties are involved, removing trust.

  2. A decision can be made by a single party and requires trust.

1 Like
#5865
  • What does it mean when we say that in blockchain, consensus determine the truth?

Various nodes in the network determine the authenticity of a transaction coming in. Only upon the acceptance they are confirmed and written in to the ledger. No single authority determines the authenticity of a transaction.

  • How is this different from how truth is determined in a central database?
    Central database unlike the blockchain is not trustless. Any person maininting it with malicious intent can misuse the authority and manipulate the data.
1 Like
#5866

  1. Because there are incentives to tell the truth, you lose money if you lie.

  2. In a central database, there’s only one authority, which means there’s no consenus

1 Like
#5867

  1. If enough validators agree that a certain transaction should be added to the blockchain, it’s now regarded as truth. Participants are also incentivized monetarily to “tell the truth”.

  2. One single person can determine the “truth” of a central database. Therefore, it’s trust based.

1 Like