As you all know, the SSL/TLS protocol requires both client and server to exchange (in clear text) a random number or nonce. This is presumably used to prevent replay attacks.
It is not clear to me what the server-side nonce requirement is. Must it simply be unique? Or must it also be unpredictable? What would be the implications if an attacker could predict the nonces generated on the server side, if any?
I welcome any source of serious work around replay attacks that could help better understand the server side nonce requirements.