1 Jerome.Euzenat@inrialpes.fr Jérôme Euzenat 655 avenue de lEurope, 38330 Montbonnot Saint-Martin, France Interoperability in an open semantic web (was:

1

Jerome.Euzenat@inrialpes.fr

Jérôme Euzenat

655 avenue de l’Europe, 38330 Montbonnot Saint-Martin, France

Interoperability in an

open semantic web(was: semantically grounded transformation)

2

Outline

• Why the semantic web must be open…

• Why the semantic web must be safe…

• …research needed.

3

Semantic web

4

Semantic webs

5

Heterogeneity

• Language suitability (expressiveness…)

• Preferences

• Legacy knowledge

• Techno-diversity is good!

• Are the languages really mature?

6

Dealing with heterogeneity

• Addressing;

• Transforming;

• Trusting;

• Acknowledging;

…as infrastructure services of the semantic web.

7

Semantic failure

Current web Semantic web

!?core dumped

404

8

Semantic failure (2)

Current web Semantic web

!?

9

Semantic failure (3)

Current web Semantic web

!?

10

Safety threats

Interoperability problems can come from:

• language heterogeneity;

• model incompatibility (in modelling).

We must provide tools for dealing with these…as far as possible.

11

L

Property satisfaction

T()L’

T

, T() L’ T() => L

, L => T() L’ T()

12

Predicate expanding transformations

[Masolo]: can replace predicate symbols by arbitrary formulas.

Equivalent to articulation axioms/interpretations.

()

FOL

FOL

, FOL => () FOL()

13

Generally applicable scheme

• Even when just some data is exported from one database;

• Even when the languages are not the same;

• Even when the ontologies are not the same.

Not applicable when nothing has to be transformed.

14

Transforming

One can be built from scratch…

Printersupport

Techsupport

Printers

No transformation being available,

15

Composing transformations

daml2dlml

oil2dlml

domain2invall

oneof2cexcl

cexcl2not

Printersupport

Techsupport

Printers

16

Gathering transformations

daml2dlml

oil2dlml

domain2invall

oneof2cexcl

cexcl2not

domain2invall

Printersupport

Techsupport

Printers

17

Transforming with properties

TL’:

Printersupport

L:Tech

support

Printers

, L => T() L’ T()

Preserving consequences

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Gathering propertiesp

about

daml2dlml

oil2dlml

domain2invall

oneof2cexcl

cexcl2not

domain2invall

p < p

<

<

<

Printersupport

Techsupport

Printers

19

Proof-carrying transformationsp

<

about

daml2dlml

oil2dlml

domain2invall

oneof2cexcl

cexcl2not

domain2invall

p < p

<

<

<

Printersupport

Techsupport

Printers

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Exporting transformation and property

T

<

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Safe transformation development cycle

• Fetching transformations;

• Fetching assertions and proofs;

• Checking the proofs (or trusting the assertions);

• Composing transformations;

• Proving that the composition satisfies the required properties;

• Publishing transformation and properties.

22

Technologiesp

<

p < p

<

<

<

RDF

OMDoc

XSLT/Transmorpher

23

Research needed: theory

• Proving properties of transformations;

• Logic: interpretation of theories, higher-order;

• Language manipulation and adapting;

• Proof, properties and semantics expression languages;

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Research needed: practice

• Development of proof checkers;

• Integration in the semantic web;

• Infrastructure for trust and proof;

• Trade-off: how good is good enough?

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Summary

The semantic web needs research for:

• an infrastructure supporting heterogeneity declined along: addressing, transforming, trusting, acknowledging…

• a mechanical way to support property-enforcement when gathering knowledge: consistency, meaning-preservation, order-preservation…

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And…

I would like to see this implemented within the basic infrastructure.

We have got PGP for years and no one is using it and the INRIA is resisting to have wireless networks because it is not safe!

=> a cause of failure, not unavoidable.