Some contributions to the management of data in grids

Lionel Brunie

National Institute of Applied Science (INSA)LIRIS Laboratory/DRIM Team – UMR CNRS 5205

Lyon, France

http://liris.cnrs.fr/lionel.brunie

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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

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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 for 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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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.