Secrecy is a computational arms race. Protecting your own communications and breaking your enemy’s are two sides of the same problem, and both, pushed hard enough, demand computation. The United States did both throughout the twentieth century, and in 1952 it created an agency for it that became one of the hungriest consumers of computing power on Earth.
The idea
Codemaking and codebreaking turned cryptography into an early and enormous driver of computing. The harder the codes, the more computation it took to make and break them.
Codes as a military problem
In the Second World War the United States protected its own high-level traffic with cipher machines like SIGABA, which was never broken, while codebreaking the enemy’s traffic was understood, even then, as fundamentally a problem of pattern, statistics, and computation. The Navy’s own codebreakers, OP-20-G and the On-the-Roof Gang, are part of the same story.
Breaking the unbreakable
The VENONA project showed the other side: even a provably secure cipher falls when it is used wrong, and reading the resulting traffic took years of painstaking analysis. Cryptanalysis is relentless, and it rewards whoever can bring the most computation to bear.
The NSA
The National Security Agency was formed on 4 November 1952. It is responsible for signals intelligence, the global collection and processing of communications, and for protecting United States communications and information systems. Concentrating the nation’s codemaking and codebreaking in one agency also concentrated its appetite for computing.
The compute arms race
That appetite drove hardware. The NSA commissioned machines built specifically to attack codes at scale, such as the stream-processing Harvest, an early example of building hardware shaped like the problem. The same pressure runs forward into the public era of cryptography, through the DES standard and the arrival of public-key cryptography.
Related Notes
- SIGABA, the American cipher that held
- VENONA, reading a cipher broken by misuse
- IBM Harvest, hardware built for cryptanalysis
- DES and RSA, the public era of cryptography
- Surveillance and Privacy, the modern stakes of this power
- Computing and the U.S. Military, the cluster index
Sources
- “National Security Agency,” Wikipedia. https://en.wikipedia.org/wiki/National_Security_Agency . Supports the NSA’s formation on 4 November 1952, its responsibility for signals intelligence and the global collection and processing of communications, and its task of protecting U.S. communications networks and information systems.