preferences in semantics-based web services interactions justus obwoge [email protected]
TRANSCRIPT
Automated Web Services interactions require addressing heterogeneity/integration, dynamic change, scalability, & performance challenges
Translations to enable interoperability between disparate services
Consumers need to efficiently and flexibly locate (discovery) and connect to supplier systems
Other automation efforts: Composition, binding & execution,
Integration of user-preferences with those of semantics techniques for enabling automated services interactions
Align matching user-side heuristics and non-client mechanisms (.
Transparency in the use of notions of user-metrics
Introduction
Interresting Motivation
SOA Maturity model for Services (adopted IFEAD, 2008)
Increasing complexity
Semantics in Web ServicesSupport:
machine processability
Reasoning and Formalisation
Shared & Explicit semantics
Web Service focus Area:
Discovery, composition, execution, monitoring
Issues:
Services representation,
conceptual modelling,
increasing maturity
Semantic
s
Web Services Discovery and Location
task
Request
Web service 2
Web service n
Web service 1
Service Consumer Service Providers
f(R, A1)
f(R, A2)
f(R, An)
Match function
Matchmaking: Degree of Match
hasInput : hotel & City
hasOutput: price
hasInput: LuxuryHotel & City
hasOutput: price
inR: a request inputinA: an advertisement input degreeOfMatch(inA, inR) Paolucci et.al. ISWC02
if inR=inA then Exactif inA immediateSubclassOf inR then Exactif inA subclassOf inR then Plug-inif inR subclassOf inA then Subsumeotherwise Fail
|Exact| > |Plug-in| > |Subsume| > |Fail|
ServiceMatchmaker
Request Advertisement
Exact
RASubsume
Travel Ontology
Accommodation
HotelB&B
LuxuryHotel
Issues in semantics Matchmaking
AdvertisementAdvertisementRequestRequest
Hotel
…
…
LuxuryHotel
…
Acknowledement: Jorge Cardoso
f(R(Input), A(Input)1)
ServiceMatchmaker
Architectural construct of matchmaking: i.e. registries & broker based algorithms (Pair-wise-computations) w.r.t underlying ontology
Adequacy of the used indices in the matching: i.e. Syntactic, Semantic. & importance of accuracy in discovery e.g. weighting & distance.
Representation of “user-wish” of task for the actual matching.
A need for the Capture of user criteria & Heuristics in Services discovery
Definition of preferences – i.e. preference algebra
Base preferences {i.e. I prefer x to y in a retrieval}
Complex preference constructors i.e. (Kiessling, 2002)
User criteria and Preferences
AdvertisementAdvertisementRequestRequest
Hotel
…
…
LuxuryHotel
…
f(R(Input), A(Input)1)
ServiceMatchmaker
?
Prefs
SM candidate services
User Preference Semantics
{x=[p1, p2,…,pn]}*
Degree of Match
(for params) {y =[=, , , , ]}
Preferences enhanced Semantic matches
Integration of Semantic formalisms with Preferences
Architecture of a Preference-based approach
Semantics Logic Matchmaker
Semantic logicComponent
PreferenceComponent
Request(Elements)
Request(Attributes,
prefs)
Semantic Match (SM)
prefs SM
Advert.(Elements)
Advert.(Elements)
Semantics based Preferences & Semantics-based
Attributes
Preferences enhanced Semantic matches
ServiceRequestLoader
Semantic matching
Component
PreferencesComponent
Ranked Services Comparer
QueryWith
PreferencesElements{a1, a2…an}Preferences(x1,x2..xn}
S
ServicesS
SP
Services {s1>s2>s3…}
SP
Analysis and evaluation
Conclusions Logics-based Semantics techniques w.r.t. an Underlying
ontology improve services retrieval accuracy i.e. recall and precision space.
User-Preference over semantics enhance specifications by which resources are matched and discovered based on capabilities, and requesting contexts
Comprehensive approaches to the use of semantics in SOA are needed:
Data, function/operation, execution, QoS, Management Addressing the Complete Web Service “Metaphor” from:
Annotation, Publication, Discovery, Composition, Binding, Execution
References Kiessling, W. Hafenrichter, B. (2002) Optimizing preference queries
for Personalized Web services. Universität Augsburg Technical Report, Institute of Computer Science, University of Augsburg, July 2002
Paolucci, M. Kawamura, T. Payne, T.R. Sycara, K. (2002a) Semantic matching of web services capabilities. James Hendler (Eds), Proceedings in: The semantic web-ISWC 2002, First International semantic web conference, Sardinia, Italy, June 9-12, 2002
Thank You!!