Revving Up Replication: Communication and state management for state machine replication
Facoltà di scienze informatiche - Segreterie degli studi
Data: 5 febbraio 2026 / 14:00 - 17:00
USI East Campus, Room D2.19
You are cordially invited to attend the PhD Dissertation Defence of Eliã Rafael de Lima Batista on Thursday 5 February 2026 at 14:00 in room D2.19.
Abstract:
State machine replication (SMR) ensures fault tolerance in distributed systems by having replicas execute requests consistently. Two key aspects of SMR performance are replica communication and state management. Atomic multicast is a communication primitive that ensures reliable message propagation among replicas. State management is crucial for ensuring durability and consistent state even if some replicas fail or behave arbitrarily. We propose enhancements for these two aspects. We aim to improve atomic multicast protocols by refining the use of communication overlays among process groups, integrating the benefits of overlays while ensuring unnecessary overhead for message propagation (genuineness). Our protocol can also adapt to changing workload locality through dynamic overlay reconfiguration. We also address efficient state transfer and verification in replicated systems. We propose two different self-validating clustered data structures that enable efficient, parallel, and independently verifiable state synchronization, reduce tail latencies, improve checkpointing and recovery, and remain robust under Byzantine faults. Integration into a practical SMR framework demonstrates their effectiveness across normal and adversarial scenarios in wide-area networks.
Dissertation Committee:
- Prof. Fernando Pedone, Università della Svizzera italiana, Switzerland (Research Advisor)
- Prof. Antonio Carzaniga, Università della Svizzera italiana, Switzerland (Internal Member)
- Prof. Patrick Thomas Eugster, Università della Svizzera italiana, Switzerland (Internal Member)
- Prof. Alysson Bessani, Universidade de Lisboa, Portugal (External Member)
- Prof. Luiz Gustavo Fernandes, PUC, Brazil (External Member)
- Prof. Valerio Schiavoni, University of Neuchâtel, Switzerland (External Member)