Title: Agent%20Paradigm:%20a%20Promising%20Approach%20to%20Enterprise%20Application%20Integration
1Agent Paradigm a Promising Approach to
Enterprise Application Integration
- Paola Turci
- turci_at_ce.unipr.it
2Outline of the Lecture
? The Context ? Consolidated Approaches Open
Issues ? Research Directions ? An Agent-Based
SOA
?
3Todays Enterprise Application Issues
- Ability to change IT quickly to fit business
needs - To improve responsiveness and efficiency
- Demand for high-levels of interoperability
- Organizations feel the need to support
interoperability between separately designed
systems - Most enterprises are very heterogeneous
- Organizations want applications to have broader
reach
4Business Performance Management Institutes
Survey - 2006
- 11 percent of executives say they're able to keep
up with business demand to change
technology-enabled processes 40 percent of
which, according to the survey, are currently in
need of IT attention -
- 36 percent report that their company's IT
departments are having either "significant
difficulties" (27 percent) or "can't keep up at
all" (9 percent)
5What Characterizes Enterprise Applications?
- Usually
- Involve persistent data
- There is a lot of data
- Many people access data concurrently
- A lot of user interface screens
- Need to integrate with other enterprise
applications
6Enterprise Application Integration
- The task of making disparate applications work
together - EAI challenges
- Applications can run on multiple computers, which
may represent multiple platforms, and may be
geographically dispersed - Networks are slow and unreliable
- Applications may run outside of the enterprise by
business partners or customers - Applications are quite dissimilar
- Changes are inevitable
7Enterprise Application Integration (II)
- Criteria that should be considered when choosing
and designing an integration approach - Application coupling
- Intrusiveness
- Technology selection
- Data format
- Data timeliness
- Data or functionality
- Remote Communication
- Reliability
8Outline of the Lecture
? The Context ? Consolidated Approaches Open
Issues ? Research Directions ? An Agent-Based
SOA
?
9Integration Approaches
- Four main integration styles consolidated
- File Transfer (70s) applications share files
- Good physical decoupling
- Language and system independent
- No extra tools or integration packages are needed
- An important decision is what format to use (XML)
- Drawbacks
- Effort is required to produce and process files
- Need to agree on the filename, location and
format, the timing of when it will be written and
read, and who will delete the file - Possible semantic dissonance
- Systems can get out of synchronization
10Integration Approaches (II)
- Shared Database (80s) applications share the
same database schema, located in a single
physical database - Use of SQL-based relational databases
- Consistent data
- Drawbacks
- Integration of data
- Difficult to find a common representation
- Database may become a performance bottleneck
11Integration Approaches (III)
- Remote Procedure Invocation (90s) Each
application seen as a large-scale object or
component with encapsulated data - The communication is synchronous
- Goal
- Make RPC look as much like local PC as possible
- Advantages
- Data exchanged only as needed
- Integration of business functions, not just data
- Weaknesses
- Big differences in performance and reliability
between remote and local procedure calls - Latency
- Lack of control over other systems
- Applications tightly coupled as a local method
call
12Integration Approaches (IV)
- Messaging applications publish messages by
using a common messaging system - Agreement on the message format.
- The communication is asynchronous
- Pros
- Reliability
- Loose coupling
- But fewer assumptions mean that more is left to
do for the developer - Correlation of related messages (e.g. request and
response) - Maintaining state
- Determining order of events, to re-establish the
message sequence - Complex programming model figuring out what to
do next - Main drawback
- Individual systems are wired together via a
message flow
13 remarks about coupling
- Coupling is not inherently good or bad
- Coupling is a measure of dependency between
applications - Technology Dependency
- Location Dependency
- Temporal Dependency
- Data Format Dependency
- Tightly Coupled Systems
- Make many assumptions about each other
- Well suited for internal communication inside of
an application - Well suited for near communication, with
control over both sides of the interaction - Generally more efficient, easier to develop and
debug
14Forrester Research
- SOA's ability to save IT costs and, more
importantly, build business flexibility has
driven broad adoption 53 of enterprises are
using SOA now or will use it by the end of 2006,
and nearly one-half of large enterprises are
using SOA for strategic business transformation.
SOA is applicable to a broad range of business
and technical scenarios, and every organization
should investigate SOA and learn where and how it
can benefit them -
- May, 2006Topic Overview Service-Oriented
Architectureby Randy Heffner, Larry Fulton - An independent technology and market
research company that provides its clients with
advice about technology's impact on business and
consumers
15CIO Magazine
- According to a recent Forrester Research
survey, 46 percent of large-enterprise SOA users
(and about 27 percent of SOA users at midsize and
smaller enterprises) said they're using SOA to
"achieve strategic business transformation."
Surveys from other research companies report the
same enthusiasm - BUT
- SOA is far from being a proven concept (only
16 percent of companies in the Aberdeen survey
have more than 24 months of experience with SOA
technologies), and the companies that have had
the most success with it so far are those that
always have success with technology big
companies with big IT budgets whose business is
technology-based (think telecom and financial
services). They also tend to have supportive,
technologically sophisticated business leaders - The Truth About SOA
- June 15, 2006
16What is SOA?
- A form of distributed systems architecture,
typically characterized by the following
properties - Logical view The service is an abstracted,
logical view of actual programs, databases,
business processes, etc., defined in terms of
what it does - Message orientation The service is formally
defined in terms of the messages exchanged
between provider agents and requester agents, and
not the properties of the agents themselves. A
key benefit of this concerns so-called legacy
systems - Description orientation A service is described
by machine-processable meta data. only those
details that are exposed to the public and
important for the use of the service should be
included in the description. The semantics of a
service should be documented, either directly or
indirectly, by its description. - Granularity Services tend to use a small number
of operations with relatively large and complex
messages. - Platform neutral Messages are sent in a
platform-neutral, standardized format delivered
through the interfaces (XML)
17 what is the point?
- Most of the technology and market research
companies, which provides their clients with
advice about technology's impact on business and
consumers, agree on the fact that the adoption of
a SOA paradigm is strategic and should be part of
the most forward-looking software projects. - Nevertheless
- the paradigm shift is still quite challenging!!!
18Widgets Gadgets 'R Us An Example
- An online retailer that buys widgets and gadgets
from manufacturers and resells them to customers - Requirements
- Take Orders customers can place orders via Web,
phone, or fax - Process Orders processing an order involves
multiple steps verifying inventory, shipping the
goods, and invoicing the customer - Check Status customers can check the order
status - New Catalog suppliers update their catalog
periodically. WGRUS needs to update pricing and
availability based on the new catalogs - Announcements customers can subscribe to
selective announcements from WGRUS - Testing and Monitoring operations staff needs to
be able to monitor all individual components and
the message flow between them
Source G. Hohpe, B. Woolf Enterprise
Integration Patterns Addison Wesley
19Widgets Gadgets 'R Us (II)
Source G. Hohpe, B. Woolf Enterprise
Integration Patterns Addison Wesley
20Taking Orders
- A message-oriented middleware solution to
streamline the order entry process
Source G. Hohpe, B. Woolf Enterprise
Integration Patterns Addison Wesley
21Processing Orders
Source G. Hohpe, B. Woolf Enterprise
Integration Patterns Addison Wesley
- A typical implementation of a distributed
business process - Main disadvantage of such a solution
- Individual systems are wired together via a
message flow
22Process Manager
- Individual systems turned into shared business
functions can be accessed as services - Increases reuse and simplifying maintenance
- Interlinked by statically or dynamically defined
workflows - Services orchestrated via a Process Manager
Source G. Hohpe, B. Woolf Enterprise
Integration Patterns Addison Wesley
23Process Manager (II)
- To turn the WGRUS IT infrastructure into an SOA
it is necessary to add facilities to look up
("discover") a service from a central registry - In order to participate in this SOA, each service
would have to provide additional functions - e.g. to expose an interface contract that
describes the functions provided by the service - Each request-reply service also needs to support
the concept of a return address
24 the Vision
Legacy SW
Web Application
HTTP
CORBA
Business Process
ODBC
Java Application
RMI
Data Base
WS-BPEL
.NET REMOTING
JCA
ERP, CRM
.NET Application
Web Service
25XML SOAP WSDL UDDI
- Rely on static descriptions of service
interfaces, forcing consumers - to find and bind services at design time
- Do not address runtime service selection based on
a dynamic assessment of nonfunctional attributes - They guarantee syntactic interoperability, but
they fail to provide semantic operability
26Open Issues
- This innovative idea brings with it new
outstanding opportunities but also new great
issues - How to efficiently discover Web services
- How to allow and facilitate their composition
27Outline of the Lecture
? The Context ? Consolidated Approaches Open
Issues ? Research Directions ? An Agent-Based
SOA
?
28Agent Community
- Evidence from several research studies that
agents could represent a suitable technology
which can be used to meet the performance needs
for innovative business applications -
- Several papers attest the current interest in
using agents for developing e-business
applications, business process management and
enterprise application integration - Different works have shown how agent technology
can be leveraged if used together with other
technologies semantic Web, Web services, rule
engine and workflows
29(No Transcript)
30OMG SOA
- 2006, OMG launched a SOA SIG.
- Primary goals
- To support an MDA approach to SOA that links
architectural, business and technology views of
services, including Business Process Management
(BPM) and Event-Driven Architecture (EDA). - Identify and foster development of OMG modeling
standards for SOA that integrate with and
complement standards developed by other
organizations such as W3C, Open Group and OASIS. - To improve awareness and understanding of SOA by
OMG members. - To coordinate SOA related efforts within OMG.
- But little has been done!!!
31FIPA - Agents and Web Services Interoperability
Working Group
- Since 2005, FIPA is an IEEE Computer Society
standards organization - Interoperability and standardization efforts
- The primary objective of AWSI WG is to fill the
interaction gap between agents and web services.
Agents should be able to locate and interact with
web services seamlessly and vice versa - But most of the work has to be done!!!
32Research Directions for Service-Oriented
Multiagent Systems
- Four major trends will drive SOC and MAS research
in the next decade - Online ontologies shared representations are
emerging as models for real-world entities - Ubiquitous computing
- Computational behaviours provided in the form of
Web services and service architecture - Widespread availability of sensors and effectors
control of physical world - SOC represents an emerging class of approaches
with MAS-like characteristics for developing
systems in large-scale open environments
Huhns, M., Singh, M., Burstein, M., Decker, K.,
Durfee, E., Finin, T., Gasser, L., Goradia, H.,
Jennings, N. R., Lakartaju, K., Nakashima, H.,
Parunak, V., Rosenschein, J., Ruvinsky, A.,
Sukthankar, G., Swarup, S., Sycara, K., Tambe,
M., Wagner, T. and Zavala, L. (2005) Research
directions for service-oriented multiagent
systems. IEEE Internet Computing 9(6) pp. 52-58.
33W3C Workshop on Frameworks for Semantics in Web
Services June 2005
- Two concrete proposals
- Elicit some concrete challenges (pain points)
- Bring together the developers of the more
comprehensive technology efforts to define simple
specifications for the low-hanging fruit that
is common to all of their approaches - Semantic annotation in WS descriptions (such as
typing of inputs and outputs, expression of
preconditions and effects of primitive actions) - A simple incremental set of extensions to WSDL to
indicate references to these elements - two years after SAWSDL
- Hierarchical classification of services for
purposes of advertising and discovery - Expression of non-functional properties such as
QoS - Possibly simple uses of rules in expressing
policies of contractual commitments - two years after Web Services Policy
34Outline of the Lecture
? The Context ? Consolidated Approaches Open
Issues ? Research Directions ? An Agent-Based
SOA
?
35 the new Vision
Legacy SW
Web Application
HTTP
CORBA
ODBC
Java Application
RMI
Data Base
MAS
.NET REMOTING
JCA
ERP, CRM
.NET Application
36Agents Role
- The central role that agents should play in a SOA
scenario is - To efficiently support distributed computing
- To allow the dynamically discovering and
composition of Web services - To be successful, it is crucial
- to appropriately engineer and integrate agent
technology with other - strategic technologies
37Ontologies
- An explicit specification of a
conceptualisation Gruber93 - Research community contributions have been mainly
devoted to cope with four different issues - Formal definition of a standard language for
expressing semantics on the web (OWL) - OWL Group to refine and extend Web Ontology
Language - Development of tools to engineer ontologies
- Two co-existing realities
- Semantic web
- Object-oriented systems
- An ontology representation more in line with the
OO data model
38Ontologies (II)
- Development of ontological supports for MASs
- A communication support to perform the proper
semantic checks on a given content expression - e.g. the JADE ontological support
- Definition of specifications for semantic Web
services - Goal providing a semantic layer based on the WS
standards - relying on WSDL for WS invocation
- expanding UDDI for WS discovery
- Semantic Annotations for WSDL and XML Schema W3C
recommendation, August 2007 - OWL-S an OWL-based service ontology supplying a
core set of markup language constructs
39Modelling Level OWL and UML Compared
- UML structure is formally quite different from
OWL - Both OWL and UML are based on classes
- Key difference the notion of Property
- At first glance, the OWL property appears to be
the same as UML association or attribute, But - OWL
- Properties are first-class modelling elements
- UML
- An association is defined in terms of association
ends, which must be related to a classifier - An attribute is always within the context of a
single class - In OWL it is possible to state assertions on
properties that have no equivalent in UML
40Implementation LevelOWL and Java Compared
- Research community followed two major directions
to express the OWL semantics using an OO language - The definition of a meta-model that closely
reflect the OWL syntax and semantics. - e.g. the modelling APIs of Jena and OWL API
- The use of the Java Beans API to realize a
complete mapping between the two models
Kalyanpur et al. - PropertyChecker classes to support the semantics
of the property, axioms and restrictions - This approach lacks an explicit meta-model
41A Semantic Framework for MASs
- With the aim of providing a support for semantic
Web services discovery and invocation - WSs are supplied with a semantic description
- The discovery and invocation phases make use of
an abstract description of the service, based on
ontological concepts belonging to the domain
ontologies - Discovery semantic UDDIs are responsible of the
semantic search - Invocation mapping between the semantic
description of the service and its real
invocation - WSDL document, from the discovery phase, is used
in the invocation phase - Mapping exploiting XSLT stylesheets (e.g
MINDSWAP, OWL-S API project)
42Semantic UDDI
- UDDI has two crucial limitations
- Its search mechanism
- WSs functionality can be described using
classification schemes like NAICS, UNSPSC etc. - The usage of XML to describe its data model
- Lack of explicit semantics
- But UDDI has enough support for the
registration of semantically annotated resources - Mapping of ontology concepts to UDDI data model
using tModel structure - New API to support semantic discovery of
registered resources - Semantic discovery algorithms
43Semantic Search in UDDI
- Based on an externally created and operated
matchmaker - Semantic data are stored outside of UDDI
- A mapping of an OWL-S profile to the UDDI data
model - Changes to UDDI APIs for support of semantic
search
M. Paolucci, T. Kawamura, T.R. Payne, K. Sycara,
Importing the Semantic Web in UDDI,
Proceedings of E-Services Semantic Web Workshop
(ESSW 2002), 2002
N. Srinivasan, M. Paolucci, K. Sycara, An
Efficient Algorithm for OWL-S Based Semantic
Search in UDDI Semantic Web Services and Web
Process Composition, First International
Workshop, SWSWPC 2004 96-110
M. Klusch,, B. Fries, K. Sycara, An Efficient
Algorithm for OWL-S Based Semantic Search in
UDDI AAMAS 2006
44Business Process Management
- WSBPEL is the new standard for orchestrating
business process using web services - Joint IBM/Microsoft proposal, being standardized
through OASIS - There are some competing languages, e.g. BPML
- Supported by more platform vendors than its
predecessors that tried to achieve similar goals,
such as ebXML - BPEL is supported by Microsoft, IBM, BEA, SAP,
Hewlett- Packard, Oracle, Siebel, and others. - Choice of process engines
- Useful in defining both concrete and abstract
processes - Each activity is represented as a service with a
WSDL interface
45Goal-Oriented Autonomic Business Process
Management
- Interesting talk on Tuesday afternoon
- Giovanni Rimassa, Birgit Burmeister
- Achieving Business Process Agility
- in Engineering Change Management
- with Agent Technology
46Limitations of Description Logics
- Description Logics provides a snapshot of the
World - Describe objects in a given time frame
- They are intrinsically very static
- Difficult to represent processes (sequences of
situations) - There is no explicit notion of variables and
rules - It is impossible to say that
- X father Y and Y father Z ? X grandfather Z
- Lots of research has happened to extend RDF/OWL
(SPARQL, SWRL,, ) - Integration of Rule-Based and Agent-Based
Programming (e.g D4J)
47 48May Agents Enhance SOA?
- Integration between local and global management
- Single agent cope with local problems
- Different agents can cooperate to cope with
global problems - Communication overhead
- Agent distribution
- Agent mobility
- System dynamic upgrading
- Agent evolution
- Code mobility
- Robustness and fault tolerance
- Agent replication
49How Should an Innovative Agent-Based SOA Be?
- Enhancing interoperability through ontologies
- Enhancing security through OASIS-W3C standards
- Enable the use of workflow / rule engines
- Ontology management software are not efficient
- Security solutions for distributed systems are
limited
50Agents Workflow Integration
- High level means for service composition
- High level means for system programming when
supported by visual tool - Well known standards (i.e., xpdl ,WSBPEL, )
- Large set of software tools available
- Workflow can be used to program agent systems at
a high abstraction level - Workflow execution can be optimized by
partitioning it among agents - Agents can act as workflow engines
- System evolution can be realized updating the
workflow to be executed
51Agents Rule Engines Integration
- Logic separated from application code
- Logic can be dynamically updated adding/removing
rules - Well optimized engines
- Rules can provide agent intelligence
- Rules can be exchanged by agents for realizing
system evolution - Agents can provide the infrastructure for a
distributed rule system
52(No Transcript)
53Team
- Agostino Poggi
- Federico Bergenti
- Lorenzo Lazzari
- Marco Mari
- Alessandro Negri
- Michele Tomaiuolo
- Paola Turci
54Thanks and Acknowledgements
- I would like to thank
- Francesco Cirillo CEO XPLabs
- for the fruitful discussions
55Thank you!Hope you enjoyed it!Questions?
- Paola Turci
- turci_at_ce.unipr.it
56Selected References
- AgentLink III. Agent Technology Roadmap.
Available from http//www.agentlink.org/roadmap/in
dex.html - Akkermans, H. Intelligent E-Business - From
Technology to Value. IEEE Intelligent Systems,
16(4)8-10, 2001. - Bechhofer, R. Volz, and P. Lord. Cooking the
semantic web with the OWL API. In Proc. Int
Semantic Web Conference, pp. 659-675, Sanibel
Island, FL, 2003. - Beneventi, A., Poggi, A., Tomaiuolo, M., Turci,
P. Integrating Rule and Agent-Based Programming
to Realize Complex Systems. WSEAS Trans. on
Information Science and Applications,
1(1)422-427, 2004. - Bergenti, F., Poggi, A., Tomaiuolo, M., Turci, P.
An Ontology Support for Semantic Aware Agents. In
Proc. Seventh International Bi-Conference
Workshop on Agent-Oriented Information Systems
(AOIS-2005 _at_ AAMAS), Utrecht, The Netherlands,
2005. - Berners-Lee, T., Hendler, J., Lassila O. The
Semantic Web - A new form of Web content that is
meaningful to computers will unleash a revolution
of new possibilities. 284(5)34-43, 2001.
57Selected References (II)
- Buhler P.A., Vidal, J.M. Towards Adaptive
Workflow Enactment Using Multiagent Systems.
Information Technology and Management,
6(1)61-87, 2005. - de Bruijn, J., Polleres, A., Lara, R., Fensel, D.
OWL DL vs. OWL Flight Conceptual Modeling and
Reasoning for the Semantic Web. In Proc. of the
14th Int. World Wide Web Conference (WWW2005),
pp. 623-632, Chiba, Japan, 2005. - Fensel, D., Bussler, C. The Web Service Modeling
Framework WSMF. Electronic Commerce Research and
Applications 1(2) 113-137, 2002. - Greenwood, D., Callisti, M. Engineering Web
Service-Agent Integration. In IEEE Conference of
Systems, Man and Cybernetics, 2004. Available
from http//www.whitestein.com/resources/papers/ie
eesmc04.pdf. - Gibbins, N., Harris, S., Shadbolt, N. Agent-based
semantic web services. In Proc of the 12th
International World Wide Web Conference
(WWW2003), Budapest, Hungary, 2003. - Gutknecht, O., Ferber, J., Michel, F. Integrating
tools and infrastructures for generic multi-agent
systems. In Proc. of the 5th International
Conference on Autonomous Agents. Montreal,
Canada, 2001. - Horrocks, I. and Patel-Schneider, P. F. A
proposal for an OWL rules language. In Proc. of
the Thirteenth International World Wide Web
Conference (WWW 2004), pp. 723-731, 2004.
58Selected References (III)
- Hindriks, K.V., de Boer, F.S., van der Hoek,
W., Meyer, J.C. Control Structures of Rule-Based
Agent Languages. In Lecture Notes In Computer
Science, Proceedings of the 5th International
Workshop on Intelligent Agents V, Agent Theories,
Architectures, and Languages, Vol 1555, pp.
381-396, 1998, London, UK Springer-Verlag. - R. Kishore, H. Zhang R. Ramesh, Enterprise
integration using the agent paradigm
foundations of multi-agent-based integrative
business information systems, Decision Support
Systems, 42 (2006) (1), pp. 4878.. - Labrou, Y. Agents and ontologies for e-business.
Knowledge Engineering Review, 17(1)81-85, 2002. - Negri, A., Poggi, A., Tomaiuolo, M., Turci, P,.
Dynamic Grid Tasks Composition and Distribution
through Agents,. Concurrency and Computation
Practice and Experience, 2005. - Negri A., A. Poggi, M. Tomaiuolo, P. Turci,
Agents for e-Business Applications, In Proc.
AAMAS 2006, Hakodate, Japan 2006 - Papazoglou, M.P.. Agent-oriented technology in
support of e-business. Communication of ACM,
44(4)71-77, 2001. - Papazoglou, M.P. The World of e-Business
Web-Services, Workflows, and Business
Transactions In Lecture Notes In Computer
Science, CAiSE '02/ WES '02 Revised Papers from
the International Workshop on Web Services,
E-Business, and the Semantic Web, Vol 2512, pp.
153-173, 2002. London, UK. Springer-Verlag
59Selected References (IV)
- Silva, N., Rocha, J., Cardoso, J. E-Business
Interoperability Through Ontology Semantic
Mapping. In Proc. of the Processes and
Foundations for Virtual Organizations, pp.
315-322, 2003. Lugano, Switzerland. - Weikum G. Special Issue on Infrastructure for
Advanced E-services, IEEE Data Engineering,
24(1), 2001.