In each of those experiments, we have a function $Gen(x)$ who generates the key or a pair of keys respectively for symmetric or asymmetric algorithms. $x = 1^n$ : I read on other questions that is a $1$ string bit of length $n$, but I didnìt understood why it is used value as input to generate the key.
Asked
Active
Viewed 30 times
0
-
Welcome to Cryptography. Consider a function that takes a parameter $n$ and outputs a uniformly random $n-bit$ key. Without the $n$ what do you expect the Key-Gen outputs? Consider AES, the Key-Gen should output 128,192,256, or 5? That is the formalization and that $n$ is considered the security parameter. – kelalaka Apr 30 '21 at 07:50
-
some dupes and/or enlightening Q/A: What exactly is a “security parameter”?. What is the difference between security parameter and b-bit security? Parameterizing adversaries with security parameters. If still not clear, let us know. – kelalaka Apr 30 '21 at 07:56