Introduction: The Urban Cryptographer

Abstract

The Urban CryptographerIn this book I want to bring cryptography into mainstream thinking about cities. Cryptography supports data security and privacy online and serves as a remedy against cybercrime and information leakage.Cryptography also supports cryptocurrencies, the blockchain, non-fungible tokens (NFTs), smart contracts, and other digital innovations that permeate the so-called "smart city."Cryptographic methods and technologies at times appear exotic and external to the concerns of those of us interested in the history, design, and shaping of cities, but in what follows I will demonstrate that cities are already invested in cryptographic ideas and practices.At the very least, cities and cryptography have concepts and procedures in common.Without cryptography, communications among people and digital devices would be exposed for anyone to see, hack, and misdirect.Facilities for securing transactions are critical elements in city infrastructures.Cryptography applies procedures and algorithms to transform texts, pictures, audio, files, and information flows so they can be read only by a targeted recipient, a designated receiver.Cryptography is not new to the city.As long as cities have existed, communications would circulate, often in full sight, but with their messages hidden.I wish to claim cryptography as a major component in the perennial life of any city.Formal and informal secret signals, sometimes described simply as "codes," flourish in urban contexts.Think of a knock at the door, the subtle inflection of which is known only to the conspirators, partygoers, or lovers on either side.I think also of how people exchange cryptic text messages, or the coded calls to children and pets that dinner is ready.The urban lifeworld is infused with abstruse acoustic signals that strengthen invisible connections and define spaces.