Center for Secure Distributed Ledgers and Contracts

Selected projects

BlockchainDB

While the main application of blockchains are crypto-currencies, blockchains are recently more and more used as general-purpose databases or key-value stores. However, a major problem is that existing implementations such as Ethereum or Hyperledger provide too low throughput and that they do not scale. In this project, we develop novel architectures for high-performance scalable blockchains that can sustain the requirements of modern data-driven applications.

Code is law

We design tools for correct and secure smart contracts and provide formal analysis of smart contract based applications. We also investigate legal aspects that are needed for guaranteed code execution.

Economy of distributed ledgers

In this project, we investigate applications of distributed ledger technology and smart contracts for finance, energy, the IoT and several other areas.

Hardware-assisted ledger technology

This project uses advanced security hardware technologies to protect the distributed ledger applications against run-time attacks.

Perun: secure and scalable channel network

Perun network is a system of payment and state channels over Ethereum. Perun's channels can be virtual, which means that the payments over longer chains of channels do not require interaction with the intermediate parties.

PQChain - post quantum secure ledgers

Most of currently deployed distributed ledger technologies are not prepared to be applied in a post-quantum world. PQChain is a distributed ledger protocol that is secure against future quantum computer attacks.

Privacy and secure computation

This project aims at developing privacy preserving blockchain technology and using smart contracts for building fair multi-party computation.

News

FastKitten accepted at USENIX Security Symposium 2019.

Feb 18, 2019. Our paper, FastKitten: Practical Smart Contracts on Bitcoin, by Poulami Das, Lisa Eckey, Tommaso Frassetto, David Gens, Kristina Hostáková, Patrick Jauernig, Sebastian Faust, and Ahmad-Reza Sadeghi, was accepted at USENIX Security Symposium 2019. In this work, we enable fast execution of interactive smart contracts on Bitcoin and symilar blockchains.

Multiparty Virtual State Channels accepted at Eurocrypt 2019.

Feb 1, 2019. Our paper, Multiparty Virtual State Channels, by Stefan Dziembowski, Lisa Eckey, Sebastian Faust, Julia Hesse and Kristina Hostáková, was accepted at 38th Annual International Conference on the Theory and Applications of Cryptographic Techniques (Eurocrypt). In this work we present the first full specification of a state channel network that supports virtual multi-party state channels, i.e. state channels that can be created and closed without blockchain interaction and that support contracts with >2 parties. Additionally, through a new mechanism, called direct dispute, the worst case time complexity of our protocol is constant for arbitrary complex channels. This is in contrast to the existing virtual state channel construction that has worst case time complexity linear in the number of involved parties. In addition to the new construction, the paper provides a comprehensive model for the modular design and security analysis.

Perun accepted at IEEE Symposium on Security and Privacy 2019.

Aug 1, 2018. Our paper, Perun: Virtual Payment Hubs over Cryptocurrencies, by Stefan Dziembowski, Lisa Eckey, Sebastian Faust, and Daniel Malinowski, was accepted at IEEE Symposium on Security and Privacy 2019. In this work, we introduce Perun, a system that combines payment channels allowed on cryptocurrencies. We present a new technique called "virtual payment channels" which avoids interaction with intermediaries for every single payment.

Two papers accepted at ACM Conference on Computer and Communications Security 2018.

Aug 1, 2018. Our paper, Foundations of State Channel Networks by Stefan Dziembowski, Sebastian Faust and Kristina Hostakova, was accepted at ACM Conference on Computer and Communications Security 2018. An extension of virtual payment networks to cryptocurrencies are so-called state-channel networks. In addition to simple virtual off-chain payments, they enable the execution of complex smart contracts in dicrect channels and channel networks. In this work, we givea first full specification for general state channel networks. Moreover, we provide formal security definitions and develop security proofs showing that our construction satisfies security against powerful adversaries.

Our other accepted paper is FairSwap: How to fairly exchange digital goods, by Stefan Dziembowski, Lisa Eckey, and Sebastian Faust. In this paper we introduce FairSwap - a new protocol for a fair exchange of digital goods over smart contracts. Our solution has two distinctive features that make it particularly interesting for large files: the cost of running the smart contract on the blockchain is minimal, and instead of expensive cryptographic tools such as zero-knowledge proofs, simple hashing techniques are sufficient.

Previous news

May 17, 2018. The German Research Foundation (DFG) approved the second funding phase for the Collaborative Research Center CROSSING which has been existing at TU Darmstadt since 2014. We are very pleased that a new project "Secure and Scalable Blockchain Technology" was successfully integrated into the CROSSING phase II.

May 2, 2018. $250K granted to Perun by the Ethereum Foundation.

April 19, 2018. New Ethereum Tech Calls on Slavic Gods for Security.

April 18-20, 2018. Associated partner Prof. Stefan Dziembowski is visiting the Distributed Ledger Center to work on Blockchain Technology.

Academic Partners

Prof. N. AsokanSecure Systems Research Group, Aalto University, FinlandTrusted Systems, Consensus Schemes

Prof. Lucas DaviUniversity of Duisburg-Essen, GermanySoftware and System Security

Prof. Alexandra DmitrienkoSecure Software Systems Research Group, University of Würzburg, GermanySecurity of Distributed Systems, Self-Healing Smart Contracts, Mobile Cryptocurrencies

Prof. Stefan DziembowskiCryptology and Data Security Group, University of Warsaw, PolandCryptographic Foundations, Smart Contracts

Prof. Farinaz KoushanfarAdaptive Computing and Embedded Systems Lab, University of California San Diego, USAAdverserial Machine Learning, Hardware Security

Prof. Paul MüllerTU Kaiserslautern, adjunct to KOM – Multimedia Communications LabBlockchain Architectures and Protocols

Prof. Philipp SandnerBlockchain School, Frankfurt School of Finance & ManagementBusiness, Economics and Research Transfer

Prof. Indra SpieckerGoethe University of Frankfurt am Main, GermanyPublic Law, Information Law, Environmental Law, Legal Theory

Prof. Ivan ViscontiUniversity of Salerno, ItalyCryptographic Foundations, Security Protocols

Prof. Moti YungAdjunct Professor, Columbia University, USA

Industry Partners and Supporters

Contacts