1. protocollo e casi studio
Bitcoin:
protocollo e casi studio
Francesco Santini
Qui posso scrivere delle note
Dipartimento di Matematica e Informatica
Università di Perugia 1

2. What is and what is not
Bitcoin was invented in 2008 with the publication of a paper titled “Bitcoin: A Peer- to-Peer Electronic Cash System”, by a programmer under the pseudonym of Satoshi Nakamoto.
Bitcoin is not “simply” a digital currency, but a network of trust that could also provide the basis for so much more than just currencies.
Digital rights management, e-voting, smart contracts, national DLT (permissioned), block-chain oriented public services

3. More gold than coins
Today, 1 bitcoin = euro

4. The P2P Network

5. Chart
last bitcoin mined in year 2140

6. Nodes Bitcoin is an open source project
The first impementation is Bitcoin Core

7. Creation of keys/addresses

8. Transactions
Bitcoin addresses are pseudonyms of real individuals (one can have several pseudonyms)

9. Chain of Transactions

10. Script
A locking script is a spending condition placed on an output: it specifies the conditions that must be met to spend the output in the future
An unlocking script is a script that “solves,” or satisfies, the conditions placed on an output by a locking script and allows the output to be spent.

11. Locking and unlocking script

12. Locking and unlocking script

13. Locking and unlocking script

14. Miners and proof-of-work
After validating transactions, a bitcoin node will add them to the memory pool, or transaction pool, where transactions await until they can be included (mined) into a block
A miner aims at finding a random nonce (32 bit) that becomes part of a block and makes it have a hash that starts with a given amount of zeroes
The hash needs to be less in value than the current target. The target is a 256-bit number (extremely large) that all Bitcoin nodes share.

15. Hashing power

16. Block-chain

17. Thanks for your attention
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