I just watched the video and came back to your post for refreshers on the process used by Bitcoin.

Thanks again 

Thank you again for taking the time to answer, this is very useful to me and truly appreciated.

Thanks
CaptainFlam.

Thank you very much for spending the time to provide this thorough answer, I really appreciate it. Moreover it is spot on, and it sheds much needed light on the way the system works.

I see three elements here that I'd like to highlight:

1- It seems to me that, referring back to my initial question and from your explanation, the transaction is verified/validated (from previous transactions) by full nodes before being added top the pool of transactions to be used to mine the next block, correct?

2- Thus, mining is not about verifying transactions per say, but about "building" a valid block that, once done and validated by other nodes, "confirms" the transaction through immutable recording, would that be a fair statement?

3- In my original high-level overview, what triggered your attention as something clearly "wrong"?

Again, your feedback is very much appreciated.


 

Thank you for your answer,

If my understanding is not correct, would you mind correcting it?

If transactions are approved at the mining level, how does finding the proper hash combination verify that Person A indeed has 50 bitcoin on his account?

Hi everyone,

I have looked everywhere on the internet and beyond, I still cannot find a proper answer regarding consensus so I am turning to you experts. When does consensus happen between the moment a transaction is requested to the moment the block is confirmed and added to the chain?

Let me explain in more details.

As far as I understand it, from a high-level point of view, here's the chain of event:

1- Transaction request between A and B created

2- Transaction broadcast to full nodes for verification

3- If transaction confirmed, it is added to the pool of pending transactions to be added to the next block

4- Miners work on finding a suitable hash for the block candidate

5- First miner to find proper combination broadcasts it to other miners for verification and approval

6- Miner who found the block's hash is awarded, block gets added.

If this scenario is correct, when is the 51% consensus required? during point 2, by 51% of full nodes (regardless of whether they are miners)? during point 5, by miners especially? Both? Or am I missing something?

I have found every answer and its opposite on many different white papers from major consulting firms, so I am turning to you for insights. Please note that I am specifically talking about Bitcoin (I'm aware that papers about "Blockchain" could be referring to many different blockchains with different rules).