Immutability means the chain cannot be changed once accepted. Nothing prevents you from dropping some blocks and start mining new ones from a specific height, but the network will not accept it so you would have to fork your own chain.
Yes, the node will connect to a few seed nodes that are defied in the source code and find other peers from them. From that point on the node will start syncing the chain.
Thanks a lot for the feedback.Regarding the first question: Can a chain , if decided so , be rolled back ?If yes, would that not be changing/manipulating it? Maybe you can expand a bit please,Iâm new to this.
Regarding the second question:Could you also please expand a bit more detail about nodes or does the academy have a section about nodes and explain in depth exactly how they work?
If you want to get deeper into how it works behind the hood, You can learn in detail in our Bitcoin programming course.
Are you part of the team? Are you saying that I should first go do the course you mentioned before doing this one? Some things that I have stated in my questions donât make sense to me 100%,I could just copy what others said in their answers but I would prefer taking it serious and understand it all as I learn.Hope this makes sense to you.
Well yes, but that doesnât mean its not immutable. If you look at this from that perspective, someone can change the chain entirely if one has enough mining power to remine all the blocks and change the state of the blockchain. Its what is called probabilistic finality.
Deterministic finality requires combining additional algorithms into a more complex chain that finalizes blocks that cannot be changed after they are deemed finalized. Polkadot uses this kind of approach.
Nodes do a lot of stuff and is out of the scope of this course since its really advanced stuff and this is Bitcoin 101. If you want to start researching P2P networks I think its best to start with Bittorrent and Kademlia, a modified version of this protocol is used on Ethereum network. Bitcoin uses its own implementation. You can check the Bitcoin developer website to learn more:
Thanks a lot for the replies.So technically speaking itâs not 100% immutable or are you saying that Polkadot is ? Is probabilistic finality basically the same as double spend?
It just means that blocks canât be changed after a certain point.
No, double spend is when you spend the same UTXOs from a pending tx with a higher fee, invalidating the original tx.
But if double spend and probabilistic finality are unlikely but still technically possible which means it could be manipulated/changed or am I missing something ?
Thanks for clarifying probabilistic finality and double spend.
transparent, immutable, secure, decentralised,
It can be if you have the power to do it, which at the moment no one has. This would be extremely expensive and not much of a benefit to the one performing the attack.
Thanks for the reply and the clarity ,makes more sense now.They should make up a new word then and not call it immutable because technically it then isnât 100% immutable .Would be great to have a system that is 100% immutable/trustless/transparent.
Im really curiuos about this especially if I had all my transactions on line can they see everything (i.e. doctor visits, did I buy juice or soda at the store) some things I feel need to stay personal. how is that accomplished in De-Fi?
Defi is not private so you canât, but its not intended to buy groceries. You could use Lightning for that instead.
Decentralization and privacy.
Blockchain gives the power of wealth back to the user instead of other entities, that donât have your best interests.
Transparency is such an important aspect of blockchain technology. Ivan gave the example of Swedish politicians giving favorable housing to relatives and friends. In America our politicians award lucrative contracts to friends and family. If government business was conducted on the blockchain citizens would be able to see the overpriced contracts given. Also voting fraud would not be a question. If voting were done on the blockchain there could be no question as to funny business. Another issue the blockchain solves is peer to peer interaction. Often a purchaser will claim a good was not provided or was damaged. Paypal and credit card companies often side with the consumer leaving the seller at a disadvantage.
When I was studying the Immutability part of the course one question popped up in my mind.
There was a massive power outage in China I think. That tanked the price of bitcoin or eth for a day or more I think.
If blockchain is immutable how can we deal with power losses? Imagine power companies just disabling power for some farms or some crazy-ass government as well? I mean china just banned BTC.
I wanna know a great counterargument against this.
I donât see any connection between power outages and immutability. If part of the network goes down, others will take over the load.
according me ,blockchain is something which can solve the difficulties faced by our financial system across the worldâŚthere no need to face cumbersome procedures faced by banks as from nowonwards everything will be decentralised and no need of middleman. returns are way higher in these platforms.
The benefits of Blockchain technology is based on itsâ distributed, decentralized and trustless nature.
Benefits such as
transparency - transaction ledger for public addresses is open to viewing.
efficiency - more efficient due to decentralization and removal of third parties such as payments processors which facilitates faster transactions by allowing Peer to peer cross-border transfers with a digital currency. This is managed through smart contracts.
security - each new transaction is encrypted and linked to the previous transaction. This is formed by a mathematical algothrm and it is impossible to be altered once formed.
tracebility - With the blockchain ledger, each time an exchange of goods is recorded on a Blockchain, an audit trail is present to trace where the goods came from. This can not only help improve security and prevent fraud in exchange-related businesses, but it can also help verify the authenticity of the traded assets.