Is Guillou-Quisquater existentially unforgeable against adaptive message attack under a random oracle model?
First of all, the Guillou-Quisquater digital signature scheme is: Note everything is $\bmod n$. Message is denoted by $m$. Private key: $s$ Public key: Hash function $H$, $e$, ...
Is this true that whenever you design a protocol using a hash function, you must prove its security under the random oracle? I mean, is it possible to devise a protocol $P$ using a function $H$, and ...
What is the "Random Oracle Model"? Is it an "assumption" akin to the hardness of factoring and discrete log? Or something else? And why do some researchers have a strong distrust of this model?