Trust in Computer Systems and the Cloud

CHAPTER 6Blockchain and Trust

Another strong movement within computing is the use of blockchains. Originally associated solely with cryptocurrencies—of which Bitcoin is the oldest and best-known—blockchains are now being employed for uses from tracking chickens through the supermarket supply chain¹ to allowing individuals to control who gains access to their personal data.²

Bitcoin and Other Blockchains

Bitcoin, like all other blockchain-based systems, is based on work by Satoshi Nakamoto (believed to be a pseudonym) and first published in the whitepaper “Bitcoin: A Peer-to-Peer Electronic Cash System”.³ A full explanation of blockchains, the mathematics behind them, and their applicability is beyond the scope of this book. The original whitepaper, which provides a remarkably simple explanation, is recommended as an introduction to the subject. One of the basic concepts, however, is the linking of blocks of data to earlier blocks, to which they have a relationship, in a chain using cryptographic hash functions. The cryptographic hashes are embedded in the new blocks, and the provenance of the chain of blocks can be traced backward through these hash values.

Cryptocurrencies provide an ingenious alternative to relying on central banks to anchor monetary value and purchasing power, and many of the applications of blockchain are focussed on removing a central authority from a system: what we would refer to, in the context of trust, as an endorsing authority. The replacement ...