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Introduction
This page
is mirrored on the www.damlsmm.ri.cmu.edu
website.
The World
Wide Web is changing. While once conceived of and implemented
as a collection of static pages for browsing, it now promises
to become a web of services--a dynamic aggregate of interactive,
automated, and intelligent services that interoperate via
the Internet. Multiple web services will interoperate to perform
tasks, provide information, transact business, and generally
take action for users, dynamically and on demand. Such prospects
are especially important for the e-business community, providing
opportunities for conducting business faster, more efficiently,
and with greater ease than ever before. For instance, the
opportunity to manage supply chains dynamically, to achieve
market advantage, is expected to increase productivity and
add value to products. On the other hand, automatic management
of supply chains presents new challenges.
One of
the problems posed by the web of services model is the need
for a service to match service requestors with service providers,
especially when--as in real web-life conditions--services
are undiscovered, new, and/or coming and going on a rapid
basis.
In these
pages, we present our Semantic Matchmaker, an entity
that will allow web services to locate other services, provide
a solution to the problem of matching, and allow for full
implementation of interoperative service providers on the
web. Here we introduce DAML-S, a DAML-based language for describoing
service capabilities. We show how semantic matching between
advertisements and requests is performed.
Semantic
Matchmaking for Web Services Discovery
First,
we focus on the problem of locating web services on the basis
of the capabilities that they provide. The solution to this
problem requires a language to express the capabilities of
services, and the specification of a matching algorithm between
service advertisements and service requests, one that recognizes
when a request matches an advertisement. We adopt DAML-S as
a service description language, because it provides a semantically-based
view of of web services, including the abstract description
of the capabilities of the service, the specification of the
service interaction protocol, and the actual messages that
it exchanges with other web services.
The ability
of DAML-S to describe the semantics of web services can be
contrasted with emerging XML-based standards as connected
to web services. Standards such as SOAP and WSDL are designed
to provide descriptions of message transport mechanisms, and
for describing the interface used by each service. However,
neither SOAP nor WSDL are of any use for providing the automatic
location of web services on the basis of their capabilities.
Another emerging XML based standard is UDDI. It provides a
registry of businesses and web services. UDDI describes businesses
by their physical attributes such as name, address and the
services that they provide. In addition, UDDI descriptions
are augmented by a set of attributes, called TModels, which
describe additional features such as the classification of
services within taxonomies such as NAICS. But because UDDI
does not represent service capabilities, it is of no use for
locating services on the basis of what they provide.
Through
the tight connection with DAML+OIL, DAML-S supports our need
for semantic representation of services. DAML+OIL allows for
subsumption reasoning on concept taxonomies. Furthermore,
DAML+OIL allows for the definition of relations between concepts.
The main limitation of DAML+OIL is its lack of a definition
of rules and an associated reasoner. Therefore, we coupled
DAML-S with RuleML. RuleML can describe constraints related
to input and output, and also preconditions and effects for
planning.
The
Matchmaker is also a web service that helps make connections
between service requesters and service providers. The
Matchmaker serves as a "yellow pages" of service capabilities.
The Matchmaker allows users and/or software agents to find
each other by providing a mechanism for registering service
capabilities. Registration information is stored as advertisements.
When the Matchmaker agent receives a query from a user or
another software agent, it searches its dynamic database of
advertisements for agents that can fulfill the incoming request(s).
Thus, the Matchmaker also serves as a liaison between a service
requester and a service provider.
Our DAML-S
Matchmaker employs techniques from information retrieval,
AI, and software engineering to compute the syntactical and
semantic similarity among service capability descriptions.
The matching engine of the matchmaking system contains five
different filters for namespace comparison, word frequency
comparison, ontology similarity matching, ontology subsumption
matching, and constraint matching. The user configures these
filters to achieve the desired tradeoff between performance
and matching quality.
In this
site, we show actual DAML-S profiles in some detail. Then,
we will present a matching algorithm between advertisements
and requests described in DAML-S that recognizes various degrees
of matching. We will show how DAML-S and an implemented version
of the matching algorithm are used to provide capability matching
to the UDDI registry. Click
here for instructions for using the Semantic Matchmaker.
See the
Agent Transaction Language
for Advertising Services (ATLAS) website for our work
in describing, advertising and matching service descriptions
using DAML. The result of this (in conjunction with the DAML-S
coalition) is "DAML-S".
A Partial
List of Publications on Middle Agents, Matchmakers, and the
Semantic Web follows. See Publications
page for complete listing.
-
Massimo
Paolucci, Takahiro Kawamura, Terry R. Payne, Katia Sycara;
"Semantic Matching of
Web Services Capabilities." Forthcoming in Proceedings
of the 1st International Semantic Web Conference (ISWC),
2002.
- Massimo
Paolucci, Takahiro Kawamura, Terry R. Payne, and Katia Sycara.
"Importing the Semantic Web in UDDI." To Appear
In Web Services, E-Business and Semantic Web Workshop,
2002.
- Katia
Sycara, Seth Widoff, Matthias Klusch and Jianguo Lu,
"LARKS: Dynamic Matchmaking Among Heterogeneous Software
Agents in Cyberspace." Autonomous Agents and
Multi-Agent Systems, Vol. 5, 173–203, 2002.
- Sycara,
K., Klusch, M., Widoff, S. and Lu, J. "Dynamic
Service Matchmaking Among Agents in Open Information Environments".
In Journal ACM SIGMOD Record (Special Issue on Semantic
Interoperability in Global Information Systems), A.
Ouksel, A. Sheth (Eds.), Vol. 28, No. 1, March 1999, pp.
47-53.
- K.
Sycara, J. Lu, M. Klusch, and S. Widoff. "Matchmaking
Among Heterogeneous Agents on the Internet." Proceedings
AAAI Spring Symposium on Intelligent Agents in Cyberspace,
Stanford, USA, 1999.
- Sycara,
K. Lu J. and Klusch M., "Interoperability
Among Heterogeneous Software Agents on the Internet."
Technical Report CMU-RI-TR-98-22, CMU
Pittsburgh, USA, October 1998.
- Anupriya
Ankolekar, Frank Huch, Katia Sycara. "Concurrent
Execution Semantics for DAML-S with Subtypes."
To Appear In The First International Semantic Web Conference
(ISWC), 2002.
- Anupriya
Ankolekar,
Frank Huch, Katia Sycara. "Concurrent Semantics for
the Web Services Specification Language DAML-S." Proceedings
of the Coordination 2002 conference, (The Fifth International
conference on Coordination Models and Languages), York,
UK, April 8-11, 2002.
-
Terry
R. Payne, Rahul Singh, and Katia Sycara. "Calendar
Agents on the Semantic Web." IEEE Intelligent
Systems, Vol. 17(3), pp. 84-86, May/June 2002. Copyright
2002, IEEE Computer Society. Also appears in IEEE
Distributed Systems Online,
Vol. 3(5), 2002.
-
Terry
R. Payne, Rahul Singh, and Katia Sycara. "RCal: A
Case Study on Semantic Web Agents." To Appear In
The First International Joint Conference on Autonomous
Agents and Multi-Agent Systems, 2002.
-
Terry
R. Payne, Massimo Paolucci, Rahul Singh, and Katia Sycara.
"Facilitating Message Exchange though Middle Agents."
To Appear In The First International Joint Conference
on Autonomous Agents and Multi-Agent Systems, 2002.
-
-
Terry
R. Payne, Massimo Paolucci, Rahul Singh, and Katia Sycara.
"Communicating
Agents in Open Multi Agent Systems." In First
GSFC/JPL Workshop on Radical Agent Concepts (WRAC)
, 2002.
-
The
DAML Services Coalition: Anupriya Ankolekar, Mark Burstein,
Jerry R. Hobbs, Ora Lassila, David L. Martin, Drew McDermott,
Sheila A. McIlraith, Srini Narayanan, Massimo Paolucci,
Terry R. Payne and Katia Sycara. "DAML-S:
Web Service Description for the Semantic Web."
To Appear In The First International Semantic Web Conference
(ISWC), 2002
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