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Service Oriented
Application Integration
(SOAI)
IT 490
NJIT
SOAI Basics
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SOAI allows sharing of application services
as well as information
The major benefit of SOAI is reusability.
Since services are shared across the
enterprise, then need for redundancy in
individual servers is reduced
What constitutes an application service, and
how does it differ from BPOIAI?
SOAI Basics
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Any method/procedure performed by a system that
is part of the enterprise may be a candidate for use
as an application service.
Examples include (but are not limited to):
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Tax rate computation
Risk analysis
Inventory control
The big difference between SOAI and BPIOAI is that
SOAI usually requires an application rewrite and
could be SIGNIFICANTLY more expensive
SOAI Basics
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Additionally, user access to the services
provided by integration is usually through a
composite application (figure 4.1)
Web services are a leveraging technology
that enables SOAI
Application frameworks such as .NET as well
as object oriented middleware frameworks
like CORBA are necessary for successful
SOAI, but no single standard is required
When to Use SOAI?
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Two or more companies share common
programming logic (calculation of shipping
costs, etc)
Two or more companies wish to develop
together and split the costs associated with
the project
Small projects that share a common domain
and collaborate on a common application that
all the participants share
SOAI Techniques
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Rebuilding existing applications is a
requirement of SOAI. Two approaches are
possible:
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Move the business logic from the individual
systems over to a shared server
Rebuild all the applications using a distributed
service framework like CORBA.
Either method will require a large amount of
time/effort/resources
Web Services
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Web Services Description Language (WSDL)
provides a standard to allow developers to
advertise available web services using XML
grammar
The WSDL definition of a service serves as
an instruction list for automating how services
may communicate across platforms
In WSDL, services are simply collections of
network endpoints at the system end and the
definition of the endpoint at the network end
Web Services
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Applications that wish to share these services
simply connect to this abstract endpoint.
Discovery of web services is managed
through Universal Description, Discovery and
Integration (UDDI) which is an XML based
registry that allows users to discover and
invoke web services
Requests for services are made using the
Simple Object Access Protocol (SOAP)
Web Services
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Some typical signs that implementing web
services might be useful in the problem
domain include:
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Redundant application servers
New applications needs that leverage the abilities
of multiple systems
Information value decreases significantly when
decoupled from services that support that data
Web Services
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Web service based integrations fall into
varying models:
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Event – driven
Composite
Autonomous – distributed
Examples
Service Frameworks
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Service frameworks allow a common
approach to creation and deployment of
cross utilized objects
While the two most common are CORBA and
COM, other development frameworks exist,
such as:
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Powerbuilder
Delphi
Smalltalk