Crypto-Agility
How can I keep encryption secure in the long term?
The idea of encrypting or signing messages is ancient. The goal is to prevent unauthorized individuals from reading or altering messages. Almost as old as cryptography itself is the attempt to break it. Between these two fields, there is a race between increasingly secure cryptographic methods and increasingly sophisticated ways to break them.
What’s new is the approach of taking this never-ending race between attacks and defense into account from the very beginning. This approach is called crypto-agility. It means that wherever cryptography is used, it must be possible to quickly and easily replace or update the cryptographic methods. Crypto-agile systems are therefore those that can adapt at any time. On this page, we show where cryptography is actually used and how organizations can become crypto-agile.
Why do we use cryptography?
Cryptographic methods allow us to communicate securely online:
- We can exchange confidential data without it being intercepted.
- We can uniquely identify our digital counterpart without being deceived
- We can trust the content of messages without worrying that they have been altered.
The Four Major Threats to Cryptography
1. Increase in computing power
Moore’s Law states that the number of computational operations performed on a chip per unit of time doubles every one to two years. This can also be roughly applied to overall computing power. As a result, data can be signed or encrypted faster today than a few years ago—but attacks on these cryptographic methods have also been accelerated.
Solution: The (encryption) keys are made longer, so that even with increased computing power, it would take too long to break them.
2. Protocol and Implementation Errors
Security-related flaws are repeatedly found in software already in use.
Solution: Install patches and updates. Keep all software up to date and use the latest standards.
3. Advances in mathematics
Current cryptography is based on mathematical problems that are difficult to solve—difficult, but not impossible. Perhaps no one has yet found a simple solution. The longer the search for simple solutions remains unsuccessful, the greater the confidence in the difficulty of the mathematical problem and thus in the security of the cryptographic method. However, if a simple solution is found, the cryptographic method is insecure.
Solution: If such a new attack becomes known, one should immediately switch to a cryptographic method based on different mathematical problems.
4. Quantum Computers
While the development of better cryptographic methods and better attacks has so far resembled a race, the development of a practically usable quantum computer represents—in the truest sense of the word—a quantum leap. In one fell swoop, nearly all of the cryptography we use today would become insecure, and with it, its applications, such as secure email, online banking, secure chat applications, and much more.
Solution: Solutions are currently being developed under the umbrella term “post-quantum cryptography.” This refers to various new cryptographic methods capable of withstanding attacks by a quantum computer. The standardization of quantum-resistant cryptography—or post-quantum cryptography—is expected in the coming years, specifically by 2023/24.
