A group signature scheme allows a group member to sign messages anonymously on behalf of the group, while in case of a dispute, a designated entity can reveal the identity of a si...
Non-interactive zero-knowledge proofs play an essential role in many cryptographic protocols. We suggest several NIZK proof systems based on prime order groups with a bilinear map...
Standard security notions for encryption schemes do not guarantee any security if the encrypted messages depend on the secret key. Yet it is exactly the stronger notion of security...
We present a technique for delegating a short lattice basis that has the advantage of keeping the lattice dimension unchanged upon delegation. Building on this result, we construct...
An encrypted email is sent from Bob to Alice. A gateway wants to check whether a certain keyword exists in an email or not for some reason (e.g. routing). Nevertheless Alice does n...