Prsentation PowerPoint

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Designing Collaborative Application in Peer2Peer
Environment
Replication is an essential feature of a
distributed system, but updates cause the issue
of consistency between replicas. Strong
consistency is easy to understand but impossible
in peer2peer environment weaker models are
complex. Our Actions-Constraints Framework (ACF)
provides a formal model for modelling, comparing,
and reasoning about consistency. Developers of
distributed collaborative applications in
Peer2Peet environment need decentralized P2P
replication middleware and consistency
protocols. Telex is a Peer2Peer semantic-oriented
middleware based on Actions-Constraints
Framework. However, it is not intuitive for
collaborative-application developers to express
application semantics using the ACF. In fact,
the application design is ad-hoc and hard to
validate. I aim to facilitate Peer2Peer
collaborative application design. For that
purpose, I propose a generic methodology for more
principle designing, an extension of the ACF to
facilitate expressing the application semantics,
and a use of automatic prover to validate the
application design.
Shared Calendar Application
Non Commuting
Share Calendars
Conflict
Calendar
Calendar
Calendar
Telex Middelware Actions-Constraints Framework
(ACF)
Action
Telex Advantages

• P2P middleware
• Replication
• Consistency
• Asynchronous
• Disconnected work

Future Challenges

• ACF Extension
• Hybridizing ACF and State-Based replication
• Correlate constraints with a state.
• Dynamic constraints

Challenges
Constraint

• Ad-hoc design
• Non intuitive
• Describe application semantics
• Static Constraints
• Hard to validate

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Future Challenges

• Design Tools
• Automatic Prover
• Actions
• Constraints
• Invariants
• Validation / Count examples

• Methodology
• Any information
• Implicit/Explicit
• Shared
• Consistency
• Explicit Telex Object

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Lamia BENMOUFFOK _ Marc SHAPIRO Lip6/INRIA
REGAL Team _ Paris 6 University
Lamia.Benmouffok_at_lip6.fr