The Ethereum Blockchain: Implementation and Security Aspects

Firstly introduced in 2013, Ethereum revolutionized the concept of blockchain. Compared to the previous generation of blockchains with the main representative the Bitcoin, the Ethereum blockchain extends the applications of this technology to domains such as its transfer of information and inclusion of off-chain data inside the blockchain. Furthermore, with the introduction of smart contracts, Ethereum allows for the automatic execution of operations inside the blockchain. These represent the key steps Ethereum firstly posed to enhance the blockchain technology and lead it to its widespread application. In this chapter we present an overview of the fundamental aspects that characterize the Ethereum blockchain. We discuss both its implementation from a blockchain point of view and the fundamental algorithmic aspects that characterize its functioning. Furthermore, we discuss the known vulnerabilities and security issues related to all the presented building blocks of Ethereum. Our aim is to provide a clear state-of-the-art overview of both the implementation aspects and security of the Ethereum blockchain.