Talk by Jérémie Decouchant

Abstract:  
This talk will introduce his ongoing work on fair transaction ordering for DAG-based consensus algorithms.  
The outcomes of transactions in decentralized finance (DeFi) systems are order-dependent as they depend on the status of previously executed transactions. This has been leading to a rise in transaction reordering attacks where malicious actors try to extract value by manipulating the order of other parties’ transactions or by inserting their own at specific locations (MEV attacks). A promising defense against MEV attacks involves defining and computing a fair ordering of transactions based on the order in which they are received by the parties that order them. However, these mechanisms have been mostly designed for linear blockchains, which rely on a leader, while the most recent blockchain consensus algorithms are leaderless and DAG-based. In this work we propose Tilikum, a DAG-based protocol that implements Ordering linearizability and maintains higher performance than linear blockchains.