Quantum cryptography exploits principles of quantum physics for the secure processing of
information. A prominent example is secure communication, ie, the task of transmitting …

Emerging smart contract systems over decentralized cryptocurrencies allow mutually
distrustful parties to transact safely without trusted third parties. In the event of contractual …

We present “Ouroboros”, the first blockchain protocol based on proof of stake with rigorous
security guarantees. We establish security properties for the protocol comparable to those …

We propose a novel paradigm for defining security of cryptographic protocols, called
universally composable security. The salient property of universally composable definitions …

Smart contracts are programs that execute autonomously on blockchains. Their key
envisioned uses (eg financial instruments) require them to consume data from outside the …

We document our experiences in teaching smart contract programming to undergraduate
students at the University of Maryland, the first pedagogical attempt of its kind. Since smart …

Consensus, or state machine replication is a foundational building block of distributed
systems and modern cryptography. Consensus in the classical, permissioned setting has …

In a data-driven society, individuals and companies encounter numerous situations where
private information is an important resource. How can parties handle confidential data if they …

We present a novel Proof-of-Stake (PoS) protocol, Ouroboros Genesis, that enables parties
to safely join (or rejoin) the protocol execution using only the genesis block information. Prior …

Decades of research in both cryptography and distributed systems has extensively studied
the problem of state machine replication, also known as Byzantine consensus. A consensus …