Keynote Talk: Living on the edge, safely or: Life without consensus

Marc Shapiro Marc Shapiro
INRIA Paris (France)

ABSTRACT. The centre-of-gravity of cloud is moving towards the edge. At edge scale, the opposition between the requirements of availability and ensuring correctness precludes any single simple answer. Choosing the right trade-off is a most vexing issue for application developers. To address this, we propose an application-driven approach, Just-Right Consistency (JRC). JRC derives a consistency model that is adapted to the specific application, being sufficient to maintain its invariants, otherwise remaining as available as possible.

In order to maintain its invariants, even sequential code follows some standard patterns. We leverage mechanisms that uphold several of these patterns while maintaining availability:

  • Conflict-Free Replicated Data Types (CRDTs) ensure that concurrent updates can be merged;
  • Causal Consistency preserves relative ordering;
  • Available Transactions preserve grouping.

Together, these mechanisms form the TCC+ model. Furthermore, our CISE logic and analysis tools distinguish cases, in the remaining pattern, where the application’s semantics requires synchronisation or not. This talk presents the challenges of edge-scale computing and the basics of the JRC approach by following the concrete example of a healthcare network. This research is supported in part by European projects SyncFree and LightKone, and by ANR project RainbowFS.

BIOGRAPHY. Marc Shapiro is a Distinguished Research Scholar (DRCE) in the Regal group of Sorbonne-Université-LIP6 and Inria (Emeritus starting September 2019). His research topics concern distributed computer systems, data replication and consistency algorithms, and multicore algorithms. He led the SyncFree European project for highly-available cloud computing and storage, developing the Antidote planet-scale hybrid-consistency database, and now leads the RainbowFS ANR project. He is the co-inventor of Conflict-free Replicated Data Types (CRDTs) designed to encapsulate the complexities of data replication while ensuring availability. He invented the proxy concept, which is now universal on the Internet. Dr Shapiro’s career started with a PhD in Toulouse (U. Paul Sabatier and LAAS), followed by a post-doc at MIT, research positions at CMIRH and Inria, and a sabbatical at Cornell. He led the Cambridge Distributed Systems group at Microsoft Research Cambridge (UK) for six years. He authored 86 international publications, some in the most prestigious venues, 18 recognised software systems, and five patents.

Dr. Shapiro, a Senior Member of the ACM, is known for his dedication to organising the Informatics community and making its voice heard in Europe. He was instrumental in creating the EuroSys society and conference, and the ACM Europe Council. He is VP for Research of Société Informatique de France, the French learned society in Informatics.


All deadlines are at 23:59 AoE

March 5th, 2021, March 19th, 2021

Abstract submission deadline

March 12th, 2021 March 26th, 2021

Paper submission deadline

April 26th, 2021 April 30th, 2021

Acceptance notification

May 10th, 2021

Camera ready

May 10th, 2021

Pre-recorded talk


Revised selected papers will be published as a post-proceedings in Springer's LNCS "Lecture Notes in Computer Science"

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