In Bitcoin, in order for a transaction to be added to the pool of valid transactions that will be added to the chain block by the miners, at least 51% of the nodes/peers need to review that transaction and see that the public key issuing it A) has the funds to issue it, and B) has not spent them in another transaction.
- Does anyone know how the peers network actually keeps track of that validation evolution?
- Does each peer individually review the transaction and then send the result (valid or not) somewhere, and in this somewhere the count is made until reaching 51%?
- Or does each validating peer somehow know about the validation result of other peers?
- How does the system know when the 51% is reached? Isn't for that required to know the total number of nodes in the network? How can this be if each node is just connected to few peers?
I cannot somehow come up with an answer that does not imply a server knowing ALL the peers in the network...
Thank you very much for your help