Hello guys,


I was looking for informations about private blockchains. Some say it's crap, some say it can save money compared to a database for a company in some cases.
I'm not a developer so my vision is on the business-side. Databases are convinient and easy to implement in most systems. My question is why and in which cases a private blockchain would be better and how to implement it ?
Do you have some information about how would it save money ?


Thanks in advance if someone responds

Thanks for your time guys, everything is clear now !
It's great how people help each other on this forum

Great

And would you have a clue for my question 2 ? (I edited after I published it)

Thank you for this high-level explanation @darosior, @achow101 !
I understand it good now.

I just have a last interrogation about the validity check of signature and the hash:

1) Does Alice  (or the nodes of the network ?) verifies the signature, by checking if it can unlock Bob's public key provided in the transaction ?

2) The ECDSA algorithm hash the transaction and creates a signature using Bob's private key. Alice checks the signature using bob's public key so she is sure Bob sent the transaction, and verifies if the transaction was modified by trying to hash the transaction to see if the hash is the same that Bob sent to her ? But if you say that "the hash itself is not included anywhere", how can Alice compare the 2 hashs ?

I hope my questions are clear, I did my best ^^

Thank you for answering guys

So if I get it right,

- The transaction is signed with Bob's private key + ECDSA (if you know the process or have an article about it, I would be interested)

- Alice can decode the signature with Bob's public key.


- So,  if the transaction is not hashed, how can Alice know if the transaction has been modified ?

Hello guys,

I have a question regarding Bitcoin digital signatures :

On the Bitcoin network, when

- Bob sends a transaction to Alice's public Key and signs using his private key, what is the method used to sign ? In my understanding, the transaction would be hashed in SHA 256 and then encoded with the private key.

- Alice receives the transaction and needs to verify its validity : she decrypt the signature using Bob's public key, and this is where I don't really understand anymore. Like when she decrypts the signature, she then has the hash of the transaction right ? Because the transaction was hashed by Bob, so she can't immedialty get the original transaction at this moment, or she can ? So how can she get the original transaction with the hash of this transaction, because we can't reverse it, right ? Like if a document is hashed and encoded with a private key, then if I decrypt it with a public key, will I get the original document, or will I just get the hash of this document ?

- When she finally gets access to the transaction, then she would have to hash the transaction she received to compare the result with the hash she got ? This way she is able to know if it's bob who sent the document and if the document wasn't modified, right ?

Thank you to the guys who will respond, if any
I'm not really into cryptography or programming so it can be pretty hard to understand sometimes.

Thank you for the answers guys.

It was really helpfull.

Have a nice day.

Hello guys,

I couldn't find proper explanation to this, so I would like to ask you something.

For the Bitcoin cash hard fork, I understand that BCH ABC and SV had to do a hash competition in order to mine the maximum blocks and validate them because in the Bitcoin protocol the longest chain will be considered as valid.

But I don't exactly understand it deeply/the process :

Like, there is bitcoin cash blockchain and then 2 group of miner decide to create two smaller blockchains (ABC and SV?) How does it work ?

When guys from ABC or SV mine blocks, they do it on Bitcoin Cash blockchain right ? So why do this result in 2 different blockchain (are the blocks mined simultaneously ?) and how does it work when a group wins, like who is going to change the parameters of the Bitcoin cash blockchain once a group give up ? (to apply the opcodes of ABC for example).

I hope you see where I want to go, like I understand the general idea but I would like to understand it more deeply : the hard fork process, why the 2 chains are created and how, and how they choose the winner & apply the changes to the blockchain.



Many thanks to thoose who will respond... I'm not a developper so it can be pretty hard to understand, just want to educate myself maximum about this then to be able to answer to other people

I will also read any link you send if any.

Proof of participation

Telegram : @Will55
Twitter : @zeboxcrypto

proof of authentication.
Telegram username: @Will55
Bitcointalk profile URL: https://bitcointalk.org/index.php?action=profile;u=2106343

#Proof of ownership :
- @Will55
- https://www.facebook.com/william.detoro.1
- https://twitter.com/zeboxcrypto

Joined airdrop.

Telegram : @Will55

Joined Telegram
@Will55

Telegram username :
@Will55

Twitter :
@zeboxcrypto

Proof

Telegram @Will55

Telegram
Join@Will55