Topic: protocol modification question (Read 649 times)

thank you very much for your explanation, definetely answers my questions.


what makes the replicated blockchain (exact same source code) different from the original one? how technically does one go about doing that? does he just create a bitcoin client with his blockchain? i assume the size and all the statistics of a new blockchain would be different ?

Also what you said about  copying a transaction on the other blockchain is this what people  refer to as double spent? i thought this issue was solved?

It's already happening.

For example, litecoin is a different protocol.
dogecoin is a different protocol.

If there are enough people to support both protocols, then they both become a cryptocurrency with their own blockchain.

That's what happens when the creator of the new protocol decides to start their protocol with a new and completely separate blockchain.  If there are two competing protocols that are both attempting to claim that they are the "real" bitcoin protocol, and they are both attempting to use the current bitcoin blockchain, then the blockchain forks.  All bitcoins that exist prior to the fork exist on both blockchains.  If you create a transaction that only spends those "split" bitcoins on one of the forks, then anyone can copy that transaction and rebroadcast it on the other fork, forcing you to spend the same amount of bitcoins on the other fork.  If your transaction includes any bitcoins that were created after the fork, then that transaction is only valid on the fork where those bitcoins were created.  Meanwhile you have users and merchants mis-communicating.  Some merchants request payment in "Bitcoin" (meaning one of the two protocols) while some of their users accidentally attempt to make a payment with "Bitcoin" (meaning the other of the two protocols). This ability to copy some (but not all) transactions between the two forks, and this miscommunication could lead to loss of faith in the currency, and a reduction in use.  A long drawn out battle between the two sects could result with each side trying to convince the world that their "Bitcoin" is the "Real Bitcoin".  Eventually perhaps one of the protocols dies off (or perhaps they both do and some altcoin rises up in popularity to overtake Bitcoin as the new most widely used cryptocurrency).


Yes.  Litecoin miners can choose to only mine litecoin.  Dogecoin miners can choose to only mine dogecoin.  If the Bitcoin blockchain forks, then miners, merchants, and users all choose which protocol they are supporting by running software that accepts the blockchain that they choose.  Blocks solved on one fork are invalid on the other fork.


There have been a few minor protocol changes early on.  Mostly to fix bugs or deal with substantial problems.


From what I recall, it was pretty clear to most users at the time that the changes were necessary and weren't controversial (although it is possible that I'm looking at history through rose colored glasses).  Therefore, the changes were overwhelmingly accepted very quickly.  If there were a few stragglers, they realized quickly that their ability to maintain their own software and their own blockchain would be counter-productive and relatively useless.
 

Coinbase might like to call what they offer their users a "wallet", but it really isn't. With a "wallet" you maintain full control of your private keys and therefore your bitcoins.  If you don't have exclusive control of your private keys, then you don't really have any bitcoins.  What Coinbase generally offers is an "account".  Like a bank account, you no longer own or control the money (your bitcoins) when you send them to Coinbase.  Instead you turn your bitcoins over to them, they take full control of the bitcoins and in exchange they create a account balance in their own database.  Then they promise to send an equivalent amount of their bitcoins wherever you want upon your request.


Since the coins were received by them before the fork, they would control both copies of the bitcoins (from both forks).  It would be up to them how they want to handle that.  They could choose to exclusively support only one of the forks and abandon all the bitcoins from the other fork.  They could choose to support both forks and make sure that they are careful to keep the bitcoins from each fork secure and available to you.  They could be incompetent and accidentally end up with some of the bitcoins stuck on only one fork and other bitcoins stuck on only the other fork.  If you turn your bitcoins over to a third party and don't have exclusive access the the private keys, then you are making the choice to turn control of your finances over to them and accepting the fate of whatever they do whether you like it or not.

thanks for your detailed answer

Say if people can't find consensus, what would happen if there was 2 different blockchain ? what will be the consequences of that?

Also can miners chose to mine only in a particular blockchain?

A modification was done already in the blockchain correct? did everyone consent to that?


If i have a wallet at coinbase for example and they decide to follow a modification which my btc client didn't agree on and didn't update, would i be able to send those coins from coinbase to my btc clients?

Not enough information available to determine the intelligence or motives of the person in question.


You do.  And I do.  And everyone does.

Bitcoin is a consensus system.  It exists only through the consensus of the users.  You choose which protocol changes youa re willing to accept when you choose to use software that implements those protocol changes.  The source code for the reference client is publicly available.  Any body can modify the protocol however they like (or hire someone to modify it for them if they don't know how).  The tricky part is convincing ALL the other users that they want to use your new modifications.  If you can't convince people to run your software, then your changes have no effect.


Computer programmers create full nodes (such as Bitcoin Core) and light nodes (such as MultiBit).  Generally they are very careful NOT to change the protocol, because consensus is very difficult.  As long as they don't change the protocol (and instead simply add features and enhancements that make it easier, safer, and more useful to use the current protocol) they don't need to worry about gaining consensus.

If enough people feel that a protocol change is necessary, they write a node program (or modify an existing one) to implement the new protocol changes.  They try to convince as many people as possible that their change is necessary or very important.  If they are successful, then the vast majority of users choose to update their nodes and wallets to use the new protocol.  If they are unsuccessful, then the vast majority of users refuse to update their software to use the new protocol.


If it is centralized and run by the government, then there will be no need for a blockchain.  The purpose of the blockchain is to provide an official record of the order of transactions in a decentralized way.  If you are using a centralized crypto currency, then the organization in charge can simply decide what the order of transactions is.  Mining and blockchains lose their purpose. 


That can only be accomplished by convincing an overwhelming majority of users that the limit should be changed and convincing them to switch to the new protocol with the new limit.

just saw this video http://bitcoinexaminer.org/us-treasury-fears-islamic-state-using-bitcoin-fund-terrorist-activities/

at 1.14.40 guy said:

"government backing this technology could be the killer app" OMG is he an idiot or illuminati puppet?


I was wondering who decides to make changes to the bitcoin blockchain and how is it decided? what is the exact process?

and what are the probability that the blockchain becomes centralized and backed by government one day? surely they would change the 21M limit too wouldn't they?

I'm not too concern as there are a lots of alternatives just curious.