Un peu de recherche…
Jan 12, 2016
Un peu de recherche…
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LIRIS/DCS/DRIM
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Nostalgia: an overview of the past10 years
• Some contributions to the management of data in grids
• Some contributions to Pervasive/Ubiquitous Systems… and other distributed systems (incl. security and privacy)
Some contributions to the management of data in grids
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Computing/Data Grid (1)
“coordinated resource sharing and problem solving in dynamic, multi-institutional virtual organisations” (I. Foster)
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Computing/Data Grids (2)
• Large scale
• Unpredictability, dynamicity
• Security, privacy
• Resource heterogeneity and usage diversity
• Decentralized administration
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Monitoring de grilles
• Where to place instances (replicas) of a service?• What resource (set of resources) (what service) use?• Condition: monitor the grid state: CPU load, network load…• Design and implementation of a grid service that processes high-
level information requests that represent the user’s specific needs in terms of resources
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Hôte C
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NDS : Network Distance Service
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Grid access control: Sygn
Mechanisms for delegation of rightsFile group operations
• Permission = Authorization Certificate (AC) :– Issuer – Owner – Capability (access
control object + authorized action)
– Validity– Signature
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Encrypted Storage for Data Grids: Crypstore
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Management of a Cooperative Cache in Grids
cachecache
cache
cache
organization
organization
GRID
data
organization
data
Collective Coordinator
Monitoring operations• data description• processed requests • transfers • replacements• used storage resource• Etc.
Management operations• Set replacement method• Set default time to live• Set cache group• Set cache coordinator• Set collective work mode• Etc.
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Data Integration
Basede
correspondances
DS
Base de
correspondances
DS
DS DS
DS
Registre de services
de données
Registre deservices
de données
Médiateurnégociateur
Médiateurnégociateur
DS : Data Service(service de données)
Correspondancenégociée
Zones de négociationimbriquées
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Some Contributions to Pervasive/Ubiquitous Systems… and
Other Distributed Systems (incl. Security and Privacy)
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Pervasive, Ubiquitous, Mobile, Ambient, Ad Hoc ?
• Introduction to pervasive systems
• Hansel and Gretel are lost in the forest of PC definitions…
• Basics (1)– Mobility (wireless) / autonomy– User (or device)-centric– Context-awareness (user prefs, environment)
• Basics (2)– Lightweight appliances and devices– Proactivity
Make the digital world/information omnipresent but invisible
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PerSE
Adaptation
context
Models
•Context-Awareness•Proactivity•Service Composition
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Architecture of a PerSE Base
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PerSE Layers
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Context Modeling and Context-Aware Pervasive Applications
• Context = ?
• User/Application centric context
• Context-aware application platform
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Access Control of Mobile Users
• Chains of trust certificates: if A trusts B and B trusts C then A trusts C… to some level
• Multi-layered adaptive certificates
• Trust computing and reputation
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Privacy-Preserving Reputation Systems
• Reputation: aggregation of feedbacks
• Query agent, target agent, source agents
• Goal: computing the reputation while not revealing the individual feedbacks
• Approach: use trust relations in the reputation protocol for enforce the privacy + “cut” feedbacks into pieces (“shares”) + use cryptographic tools
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Authentication and Trust in Pervasive Systems
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Mobile Requests
• Information exchange between mobile peers (MANETs, VANETs)
• Trajectory aware geocast request routing
• Construction for each query of an ad hoc overlay of the peers that may participate to the delivery of the requested data
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Data Replication in Small Worlds
ServerOriginal content
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Replication in Ad Hoc Networks
• Issues: instability, dynamicity, faults/disconnections
• Basic idea: adapt the replication heuristics to the actual usage of the data, e.g.:– Data highly accessed => replicate– Rare data and planned disconnection => replicate– Overloaded peer => replicate most accessed data– Etc.
• Pre-requisite: access logging + exchange of access data
• Assumption: no central coordination – local decisions
• Question : can local decisions lead to an acceptable (good ?) situation ?
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Interface Adaptation and Context-Aware Browsing
of a Patient Medical Record
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Multimedia Content Adaptation
+ Adaptation of the interface wrt the end-user deviceOngoing : Content Adaptation in MANETs
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Semantic Protection of Multimedia Data
• Multimedia => access control is not a binary decision
• Access control <=> content adaptation
• Coherence/Consistence of an adaptation
• Legality of an adaptation
=> Access control = semantic adaptation decision
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Semantic Clustering of Multimedia Queries: From Query Logging to Database Content and User Profile Discovery
• Large number of data stores disseminated• Lack of indexes
• Issues :– What are the pertinent/interesting data ?– What are the users interest ?– How to process a query ?
• Logging of the users’ queries + clustering + communication of clustering info => identification of the community of users’ interests
• Logging of a the queries issued by a specific user + matching to the community clustering => identification of the user’s profile
• Usage: query optimization, data store management, recommendation, social computing, etc.
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BAR-Tolerant Publish-subscribe P2P Systems
Collaboration Modeling and Enhancing: a Game Theoretical Approach
• Byzantine-Altruistic-Rational
• Publish an information; disseminate the information to subscribers
• Systems benchmarking tool
• GT modeling of collaborative systems
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Ambient Social Networks andMessage Routing in DTN
• Ambient social networks
• Delay Tolerant Networks (DTN) and Opportunistic Networks
• Mobility traces/model
• Message routing
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Ongoing work:User-centric Ubiquitous Multi-Scale
Digital Ecosystems
• Information retrieval in P2P systems• Privacy-preserving personal data mining (EEXCESS project)• Privacy-preserving recommendation systems (EEXCESS project)• Privacy-preserving multimedia data routing• Open data and user-as-sensor based ambient social services• Game-theory-based cooperation modeling and enhancing in distributed systems• Trust and reputation in B2B networks (AttestationLegale)• Information protection in clouds• Social-aware event driven architectures• Mobile Crowd Sourcing, Sensing, and Computing: Intelligence, Aggregation, Resilience• (if opportunity) Adaptive and information value-based protection of business processes• (if opportunity) Security of the social web of things• ???
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Faites de la recherche
(au moins un peu)
!