Schiavoni, Valerio

2017-4-4, Schiavoni, Valerio

2012-1, Charles, Lucas, Felber, Pascal, Halalai, Raluca, Rivière, Etienne, Schiavoni, Valerio, Valerio, José

2009-9, Seinturier, Lionel, Merle, Philippe, Fournier, Damien, Dolet, Nicolas, Schiavoni, Valerio, Stefani, Jean-Bernard

2016-6-5, Krasikova, Sveta, Carvajal Gómez, Raziel, Borba Ribeiro, Heverson, Rivière, Etienne, Schiavoni, Valerio

Self-organizing construction principles are a natural fit for large-scale distributed system in unpredictable deployment environments. These principles allow a system to systematically converge to a global state by means of simple, uncoordinated actions by individual peers. Indexing services based on the distributed hash table (DHT) abstraction have been established as a solid foundation for large-scale distributed applications. For most DHTs, the creation and maintenance of the overlay structure relies on the exploration and update of an already stabilized structure. We evaluate in this paper the practical interest of self-organizing principles, and in particular gossip-based overlay construction protocols, to bootstrap and maintain various DHT implementations. Based on the seminal work on T-Chord, a self-organizing version of Chord using the T-Man overlay construction service, we contribute three additional self-organizing DHTs: T-Pastry, T-Kademlia and T-Kelips. We conduct an experimental evaluation of the cost and performance of each of these designs using a prototype implementation. Our conclusion is that, while providing equivalent performance in a stabilized system, self-organizing DHTs are able to sustain and recover from higher level of churn than their explicitly-created counterparts, and should therefore be considered as a method of choice for deploying robust indexing layers in adverse environments.

2011-6-13, Schiavoni, Valerio, Rivière, Etienne

2009-6-22, Kermarrec, Anne-Marie, Pace, Alessio, Quema, Vivien, Schiavoni, Valerio

2014-9-8, Matos, Miguel, Schiavoni, Valerio, Rivière, Etienne, Felber, Pascal, Oliveira, Rui

Gossip-based live streaming is a popular topic, as attested by the vast literature on the subject. Despite the particular merits of each proposal, all need to implement and deal with common challenges such as membership management, topology construction and video packets dissemination. Well-principled gossip-based protocols have been proposed in the literature for each of these aspects. Our goal is to assess the feasibility of building a live streaming system, LAYSTREAM, as a composition of these existing protocols, to deploy the resulting system on real testbeds, and report on lessons learned in the process. Unlike previous evaluations conducted by simulations and considering each protocol independently, we use real deployments. We evaluate protocols both independently and as a layered composition, and unearth specific problems and challenges associated with deployment and composition. We discuss and present solutions for these, such as a novel topology construction mechanism able to cope with the specificities of a large-scale and delay-sensitive environment, but also with requirements from the upper layer. Our implementation and data are openly available to support experimental reproducibility.

2011-6-7, Seinturier, Lionel, Merle, Philippe, Rouvoy, Romain, Romero, Daniel, Schiavoni, Valerio, Stefani, Jean-Bernard

2006-6-24, Schiavoni, Valerio, Quema, Vivien