Rachid Guerraoui receives ERC Proof of Concept Grant

IC Professor Rachid Guerraoui is a global expert in the field of reliable distributed algorithms. © 2018 EPFL / Alain Herzog

IC Professor Rachid Guerraoui is a global expert in the field of reliable distributed algorithms. © 2018 EPFL / Alain Herzog

Rachid Guerraoui, head of the Distributed Computing Laboratory (DCL) in the EPFL School of Computer and Communication Sciences, has been awarded a prestigious European Research Council (ERC) Proof of Concept (PoC) Grant.

PoC grants, which are part of the European Union research and innovation program Horizon 2020, are awarded annually to researchers who are already principal investigators of an ERC-funded project. The grants provide €150,000 over 18 months for these researchers to further investigate the commercial or societal potential of their projects.

Guerraoui, a global expert in the field of reliable distributed algorithms, received one of 54 PoC grants for 2019 for his project, “Asynchronous Trustworthy Transfers” (AT2). The funds will allow him to further explore the real-world viability of concepts developed as part of his €2.14 million ERC Advanced Grant project, Adversary-Oriented Computing (AOC).

A simpler solution to digital trust

As part of the five-year AOC project, Guerraoui worked on classifying distributed computing problems including consensus, which refers to how agreement is established on transactions in distributed systems like blockchains.

The consensus problem is one of the most-studied problems in distributed computing, and solutions usually involve tradeoffs between digital trust and system efficiency. But Guerraoui discovered that in order to build a tokenized payment system like Bitcoin, it is enough to solve a problem called “secure causal broadcast” to implement trust. This is significantly simpler than consensus and is not subject to classic impossibility results and lower bounds. 

After this discovery, Guerraoui and his team devised a generic protocol to solve the secure causal broadcast problem: a class of “consensusless” algorithms, which they dubbed Asynchronous Trustworthy Transfers, or AT2. This protocol can support any tokenized application without sacrificing efficiency or trust.

With the PoC funding, Guerraoui now aims to validate this protocol in concrete and realistic settings.