Pseudorandom ensemble

In cryptography, a pseudorandom ensemble is a family of variables meeting the following criteria:

Let $U=\{U_n{\}}_{n\in \mathbb{N}}$ be a uniform ensemble and $X=\{X_n{\}}_{n\in \mathbb{N}}$ be an ensemble. The ensemble $X$ is called pseudorandom if $X$ and $U$ are indistinguishable in polynomial time.

References

• Goldreich, Oded (2001). Foundations of Cryptography: Volume 1, Basic Tools. Cambridge University Press. . Fragments available at the author's web site.