More and more we see stories appearing, like this one in HBR by MIT Media Lab’s Joi Ito and crew. It praises the power of blockchain as a disruptive technology, on par with how “the internet” changed everything.

I am always surprised to see that these far-reaching predictions are made, without diving into the technology itself. This weekend I would like to read about some of the technologies that predate blockchain, as they are its fundamental building blocks.

Blockchain technology first came on the scene in 2008, as a core component of the bitcoin cryptocurrency. Blockchain provides transactional, distributed ledger functionality that can operate without a centralized, trusted authority. Updates recorded in the ledger are immutable, with cryptographic time-stamping to achieve serializability. Blockchain’s robust, decentralized functionality is very attractive for global financial systems, but can easily be applied to contracts, or operations such as global supply chain tracking.

When we look at the foundation of blockchain, there are three papers from the nineties that describe different components whose principles found its way into blockchain. The 91 paper by Haber and Stornetta describes how to use crypto signatures to time-stamp documents. The 98 paper by Schneier and Kelsey describes how to use crypto to protect sensitive information in log files on untrusted machines. Finally, the 96 paper by Ross Anderson describes a decentralized storage system, from which recorded updates cannot be deleted.

I hope these will enlighten your fundamental understanding of blockchain technology.

“How to Time-Stamp a Digital Document”, Stuart Haber, and W. Scott Stornetta, In Advances in Cryptology – Crypto ’90, pp. 437–455. Lecture Notes in Computer Science v. 537, Springer-Verlag, Berlin 1991.

“Cryptographic Support for Secure Logs on Untrusted Machines”, Bruce Schneier, and John Kelsey, in The Seventh USENIX Security Symposium Proceedings, pp. 53–62. USENIX Press, Januar 1998.

“The Eternity Service”, Ross J. Anderson. Pragocrypt 1996.