Bitcoin

Bitcoin was proposed by Nakamoto (2008) as the first electronic payment system, which fully relies on cryptographic primitives in order to work over a purely peer-to-peer system, where everyone can participate in spending funds to other users without the need for a trusted third party. This chapter first introduces the basic ideas of Satoshi Nakamoto, who defined an electronic coin as a chain of digital signatures. It explains how the addresses in Bitcoin are derived, and how the elliptic curve cryptography (ECC) key pair is used in order to transact funds from one user to another. For this, it shows how the transactions are constructed in Bitcoin, based on the most common transaction, which is the Pay-to-Public-Key-Hash transaction. The last section then shows how the transactions are permanently stored in the public ledger, the blockchain, and how the miners solve the Proof-of-Work in order to safeguard the records.