Ilyas Toumlilt

I am currently stuck in the PhD graduation ceremony at Sorbonne University, where the tradition is that each of the 2xx PhDs of the class goes on stage to get his diploma, his sash and take a picture with the directors... So I take advantage of this long moment of waiting to make a last article to summarize my contributions of these 4 years of thesis.

Build mobile, edge, and collaborative applications that just work, anywhere across the edge-cloud spectrum, seamlessly whether connected or not. Choose your deployment, in the cloud or on-premise; Concordant maintains app consistency and keeps it up and running. Develop applications quickly, with a single code base for multiple devices. Reduce time to market, and focus on your customers' needs.

My thesis defense, completed within the LIP6 Delys INRIA team and titled "Colony: A Hybrid Consistency System for Highly-Available Collaborative Edge Computing".
Defended on Tuesday 21 December 2021 at 13:00 (Paris Time).
This article contains an archive of the video presentation, the thesis manuscript and related blog posts.

Edge applications, such as gaming, cooperative engineering, or in-the-field information sharing, enjoy immediate response, autonomy and availability by distributing and replicating data at the edge. However, application developers and users demand the highest possible consistency guarantees, and specific support for group collaboration. To address this challenge, Colony guarantees Transactional Causal Plus Consistency (TCC+) globally, strengthened to Snapshot Isolation within edge groups. To help with scalability, fault tolerance and security, its logical communication topology is forest-like, with replicated roots in the core cloud, but with the flexibility to migrate a node or a group. Despite this hybrid approach, applications enjoy the same semantics everywhere in the topology. Our experiments show that local caching and peer groups improve throughput and response time significantly, performance is not affected in offline mode, and that migration is seamless.

Keywords : Causal Consistency, Collaborative Computing, Edge Computing, CRDTs, Peer-to-Peer Systems.

AntidoteDB is a highly available geo-replicated key-value database. AntidoteDB provides features that help programmers to write correct applications while having the same performance and horizontal scalability as AP/NoSQL databases. Furthermore, AntidoteDB operations are based on the principle of synchronization-free execution by using Conflict-free replicated datatypes (CRDTs).

This project is an Open Source collaboration from my thesis at Sorbonne University, on the LightKone and the SyncFree European projects.