Publications de Davide Frey | EPFL Graph Search

Differentiated consistency for worldwide gossips

Eventual consistency is a consistency model that favors liveness over safety. It is often used in large-scale distributed systems where models ensuring a stronger safety incur performance that are too low to be deemed practical. Eventual consistency tends ...

2022

Collaborative Filtering Under a Sybil Attack: Similarity Metrics do Matter!

Rachid Guerraoui, Anne-Marie Kermarrec, Antoine Rault, Davide Frey, Florestan Laurentin Marie De Moor

Recommendation systems help users identify interesting content, but they also open new privacy threats. In this paper, we deeply analyze the effect of a Sybil attack that tries to infer information on users from a user-based collaborative-filtering recomme ...

IEEE2018

Privacy-preserving distributed collaborative filtering

Rachid Guerraoui, Anne-Marie Kermarrec, Davide Frey

We propose a new mechanism to preserve privacy while leveraging user profiles in distributed recommender systems. Our mechanism relies on two contributions: (i) an original obfuscation scheme, and (ii) a randomized dissemination protocol. We show that our ...

Springer Wien2016

Privacy-Preserving Distributed Collaborative Filtering

Rachid Guerraoui, Anne-Marie Kermarrec, Davide Frey

We propose a new mechanism to preserve privacy while leveraging user profiles in distributed recommender systems. Our mechanism relies on (i) an original obfuscation scheme to hide the exact profiles of users without significantly decreasing their utility, ...

Springer International Publishing2014

Trust-aware peer sampling: Performance and privacy tradeoffs

Anne-Marie Kermarrec, Davide Frey, Julien Michel Stainer

The ability to identify people that share one's own interests is one of the most interesting promises of the Web 2.0 driving user-centric applications such as recommendation systems or collaborative marketplaces. To be truly useful, however, information ab ...

Elsevier Science Bv2013

WHATSUP: A Decentralized Instant News Recommender

Rachid Guerraoui, Anne-Marie Kermarrec, Davide Frey

We present WhatsUp, a collaborative filtering system for disseminating news items in a large-scale dynamic setting with no central authority. WhatsUp constructs an implicit social network based on user profiles that express the opinions of users about the ...

2013

Boosting Gossip for Live Streaming

Rachid Guerraoui, Anne-Marie Kermarrec, Maxime Monod, Davide Frey

Gossip protocols are considered very effective to disseminate information in a large scale dynamic distributed system. Their inherent simplicity makes them easy to implement and deploy. However, whereas their probabilistic guarantees are often enough to di ...

2010

Heterogeneous Gossip

Rachid Guerraoui, Anne-Marie Kermarrec, Maxime Monod, Davide Frey

Gossip-based information dissemination protocols are considered easy to deploy, scalable and resilient to network dynamics. Load-balancing is inherent in these protocols as the dissemination work is evenly spread among all nodes. Yet, large-scale distribut ...

Springer2009

Stretching Gossip with Live Streaming

Rachid Guerraoui, Anne-Marie Kermarrec, Maxime Monod, Davide Frey

Gossip-based information dissemination protocols are considered easy to deploy, scalable and resilient to network dynamics. They are also considered highly ﬂexible, namely tunable at will to increase their robustness and adapt to churn. So far however, the ...

2009