cross pond high tech

A DANE, A Swede, a German and a Dutchman walk into a bar. It is 1979 and spooks from the four countries are conferring in Munich over dark and malty lagers. For years, they had co-operated in the business of signals intelligence, or SIGINT—intercepting messages and cracking codes—and wanted a name for their budding spy pact. “They looked at their glasses, filled with Doppelbock beer of the local brand Maximator,” writes Bart Jacobs, a Dutch computer-science professor, “and reached a decision”.

In a paper published last month, Mr Jacobs publicly revealed the existence of the Maximator alliance for the first time, to the considerable irritation of those who had kept it under wraps for decades. The group was formed in 1976, when Denmark joined forces with Germany and Sweden to intercept and decipher messages sent by satellites, a burgeoning method of communication. The Netherlands joined two years later, bringing its intercept stations in the Carribean to the table, and France in 1985. The group is alive and well today.

Maximator’s history is a fine illustration of the layers of chicanery involved in good cryptology. As well as plucking signals out of the ether, the group would swap details of weaknesses in cipher machines which encrypted diplomatic and military messages. Luckily for them, says Mr Jacobs, the companies that made those machines “were mostly controlled by Western intelligence organisations.” Crypto AG, a Swiss firm that dominated the global market, turns out to have been jointly owned by the CIA and its German counterpart, the BND. They would sell rigged machines to friends and enemies alike, including several NATO countries.

Can we outsource medical analysis without giving away our medical information? Can we do biometrical identification without revealing our characteristics? Can we make statistics on data that we do not know? Yes we can, thanks to a cryptographic mechanism called “homomorphic encryption”.

Cryptography has known many transformations over the years. Many centuries ago, it was first used to protect military and political communications. Though very simple, the mechanisms then devised are still the foundation of current cryptography. The introduction of the computer during Second World War considerably increased the computation capacity. This increase reflected on cryptography in the late 70’s, when public key cryptography was invented. Cryptography became a thriving scientific field. Numerous academic works were produced, commercial standards were set and cryptographic algorithms began to secure our daily life. Today, cryptography is everywhere: in our credit cards, in our phone communications, in our internet browsing, etc.
But new services are today under deployment, such as mobile services, cloud computing, BigData or IoT. These services generate and process a huge amount of personal and sensitive information. As users become more and more concerned about their privacy, and industries want to protect their sensitive data, a new challenge arises for cryptography. Indeed, if this data was to be simply encrypted, processing it would be impossible. This leaves users and service providers with a dilemma: choose between usability and confidentiality of these sensitive data. Here comes fully homomorphic encryption!