Conjectured pseudorandom functions

daidar3118_at_hotmail.com
Date: 04/30/05 

Date: 29 Apr 2005 16:41:03 -0700

What are the conjectured pseudorandom functions with arbitrary input
length commonly used in practice? Is it necessary to choose the key of
a pseudorandom function uniformly from the key space in order to ensure
its randomness? Could we just feed the output of the pseudorandom
function on an input x as the key to another pseudorandom function?