General concept

A cryptosystem should be secure even if everything about the system, except the key, is public knowledge.

"Il faut qu’il n’exige pas le secret, et qu’il puisse sans inconvénient tomber entre les mains de l’ennemi"

In other words, "cipher" should remain secure even if an adversary knows the specification of the cipher.

To avoid...


References

  1. https://intensecrypto.org/public/lec_01_introduction.html