Information Theoretically Secure Key Agreement and Related Topics

Information-theoretically Secure Key Agreement over Partially Corrupted Channels

Key agreement is a fundamental cryptographic primitive. It has been proved that key agreement protocols with security against computationally unbounded adversaries cannot exist in a setting where Alice and Bob do not have dependent variables and communication between them is fully public, or fully controlled by the adversary. In this paper we consider this problem when the adversary can “partia...

Information-theoretically Secure Secret-key Agreement by Not Authenticated Public Discussion 1

All information-theoretically secure key agreement protocols (e.g. based on quantum cryptography or on noisy channels) described in the literature are secure only against passive adversaries in the sense that they assume the existence of an authenticated public channel. The goal of this paper is to investigate information-theoretic security even against active adversaries with complete control ...

Information Theoretically Secure Databases

We introduce the notion of a database system that is information theoretically secure in between accesses—a database system with the properties that 1) users can efficiently access their data, and 2) while a user is not accessing their data, the user’s information is information theoretically secure to malicious agents, provided that certain requirements on the maintenance of the database are r...

Information-Theoretically Secure Key-Insulated Multireceiver Authentication Codes

Information-Theoretically Secure Byzantine Paxos

We present Information Theoretically secure Byzantine Paxos (IT ByzPaxos), the first deterministic asynchronous Byzantine consensus protocol that is provably secure despite a computationally unbounded adversary. Previous deterministic asynchronous algorithms for Byzantine consensus rely on unproven number theoretic assumptions (i.e., digital signatures) to maintain agreement. IT ByzPaxos instea...