First Workshop on Blockchain Technologies and Trusted Execution Environments

COVID-19: BlockTEE’22 is planned as a physical, in-person event, with certain support for remote presence, both for speakers and for other participants who are unable or unwilling to come. Depending on the pandemic situation, we may have to make a decision whether to cancel the physical component of the event or not.


Blockchains and Trusted Execution Environments (TEE) are popular emerging technologies, enabling new or existing use cases to be deployed under stronger security and trust models. Blockchains and TEEs have been combined in the past to enhance the performance, security and applicability for blockchains. In this workshop, we invite novel combinations of these two technologies. Some of the topics of interest include, but are not limited to:


The first page must contain (1) title, (2) author names and affiliations, (3) contact author’s email, (4) abstract, and (5) indication of whether the paper is a full paper or a position paper as detailed below:

Contributions should be submitted electronically as PDF, using the Springer LNCS style to the conference submission website ( Each paper will undergo a thorough process of peer reviews by the Program Committee. Reviewing is single-blind: author name(s) should appear.

We will have an hybrid publication model. In the spirit of a workshop, the aim of this hybrid model is to facilitate the exchange of ideas and experiences via presentations of preliminary research results and ongoing work, as well as presentations of research work to a focussed audience. Therefore, authors will be able to choose, after paper acceptance, if:

The author’s decision of publication mode is done after notification and hence has no bearing on the decision of whether to accept or reject a submission. Submission implies that at least one author will register and attend the conference if the paper is accepted. The registration fees for accepted papers is due regardless of the selected publication model.

Important dates

Program chairs

Program committee

Keynote Speakers

Title: Byzantine Leaderless State-Machine Replication Abstract: Recent advances in state-machine replication (SMR) protocols focus on leaderless approaches. In these protocols, each replica is on par with its peers and can be used to coordinate the execution of a state-machine command. This removes the bottleneck of leader-based techniques, improves fairness wrt. remote clients as well as availability. To date, few works exist that address arbitrary (byzantine) failures in leaderless SMR. In this talk, we try to bridge this gap. We propose the first general framework to construct correct-by-design byzantine leaderless protocols. Our framework is composed of well-identified services, such as byzantine quorums, best-effort broadcast and consensus. For a given service, many implementations exist. Some may focus on scalability, while others improve latency or security using trusted execution environments (TEE). Two use cases are given to illustrate the framework: a byzantine fault-tolerant variations of Egalitarian Paxos, and a highly scalable byzantine leaderless protocol called Wintermute. We also discuss the interest of byzantine leaderless SMR in the context of permissioned blockchains.

Bio: Pierre Sutra is Associate Professor at Télécom SudParis and a committer of the Apache Software Foundation. His work investigates the theory and practice of distributed systems, with applications to big data stores, transactional systems and storage systems. Pierre has co-authored more than 40 research publications. Over the past two years, he has published at the following top journals and conferences: ACM TOSEM, Information Processing Letters, SOSP, EuroSys, DISC and Middleware.

Title: Using SGX to Tackle Security Issues in Ethereum Meta-Transactions

Abstract: Ethereum currently backs the largest amount of existing decentralized applications (DApps) built on public blockchain platforms. Interaction with Ethereum DApps implies transactions that charge a fee. These fees complicate onboarding new users who lack the necessary cryptocurrency. Meta-transaction patterns emerged for decoupling users from paying the transaction fees. In essence, the existing meta-transaction services include a relayer mechanism forwarding the transactions and paying for these on behalf of the users. While solving the user onboarding problem, introducing an extra party in the transaction path generates multiple security issues. In this talk we examine these issues and discuss the first steps taken toward a new meta-transaction architecture that uses Intel Software Guard Extensions (SGX). We argue that integrating a trusted execution environment such as SGX at the relayer site provides the necessary security guarantees in a meta-transaction setting.

Bio: Emanuel Onica is an Associate Professor at the Faculty of Computer Science, Alexandru Ioan Cuza University of Iaşi, Romania. He received his PhD from University of Neuchâtel, Switzerland, where he worked as a scientific collaborator between 2010 and 2014. He was involved in several European projects, notably coordinating the H2020 EBSIS project between 2016 and 2018. His research interests lie in the area of parallel and distributed systems, where he is the recipient of four awards in international conferences, among which winning the DEBS Grand Challenge in 2017 and 2018. A consistent part of his work in this field has a focus on privacy and security.



When What Title and Speaker
09.00 - 09.10 welcome welcome
09.15 - 10.00 Keynote Byzantine Leaderless State-Machine Replication. Pierre Sutra
10.00 - 10.30 Invited paper SplitBFT: Improving Byzantine Fault Tolerance Safety Using Trusted Compartments. Ines Messadi, Markus Horst Becker, Kai Bleeke, Leander Jehl, Sonia Ben Mokhtar, Rüdiger Kapitza
10.30 - 11.00 Regular paper ChainBox: Using TEEs and WebAssembly to run Smart Contracts on the Edge. Kai Bleeke, Mohammad Mahhouk, Lennart Almstedt, Leander Jehl, Rüdiger Kapitza
11.00 - 11.30 coffee break coffee break
11.30 - 12.15 Keynote Using SGX to Tackle Security Issues in Ethereum Meta-Transactions. Emanuel Onica
12.15 - 12.45 Regular paper Securing Cross-Chain Asset Transfers on Permissioned Blockchains. Catarina Pedreira, Rafael Belchior, Miguel Matos, André Vasconcelos
12.45 - 13.00 closing closing
13.00 - 14.30 lunch break lunch break