Originally posted by amit taneja:
well Soa include major portion of Webservices, actually its framwork where different technologies/produc intract and integrated with each other through common BUS, and most of the communication to each other could be xml.
like in my project www.airtelworld.com , we use every damn s/w of IBM like
IBM WSAD, WAS, Process Server, IBM Adaptors, IBM Portal Server, IBM Message broker, IBM MQ Series, where different products act as plugins ...
and most product end points could be deployed as webservice
so if our differetn application can use same stuff without replication of code...
There are logical links between Web services and SOA that suggest that they
Web services provide an open-standard and machine-readable model for
creating explicit, implementation-independent descriptions of service
Web services provide communication mechanisms that are
location-transparent and interoperable.
Web services are evolving, through Business Process Execution Language
for Web Services (BPEL4WS), document-style SOAP, Web services
Definition Language (WSDL), and emerging technologies (such as
WS-ResourceFramework), to support the technical implementation of
well-designed services that encapsulate and model reusable function in a
flexible manner. Working together,Web services and SOA have the potential to address many of the technical issues that are faced when trying to build an on demand environment.
A multitude of technologies and platforms are used to support business
systems, all which need to be integrated into an SOA.
Web services are a set of open-standard technologies that are supported by
most of the IT industry and by the Web Services Interoperability (WS-I)
organization. Their basis is in simple, text-based, and open-standard
technologies such as XML and HTTP, and the fact that they can leverage
more sophisticated interoperable technologies, such as asynchronous
messaging, means that they can be supported in the vast majority of IT
environments. Increasing ubiquity and maturity of product support means that
implementing and integrating Web services will become increasingly efficient.
Business process models are a mixture of people practices, application code,
and interactions among people and systems or systems and systems.
Although SOA is an approach to architecture that must be applied to systems
and integrations, it specifies a set of principles and techniques that encourage
the encapsulation and modeling of reusable business functions and
processes. Recent and emerging trends in Web services, such as BPEL4WS
and WS-ResourceFramework, will increasingly support the modeling
concepts of SOA. In this way, process management can be centralized rather
than being part of multiple applications.
Changes to one system tend to imply ripples of change at many levels to
many other systems.
SOA specifies several principles and techniques for achieving the
encapsulation of service function and the loose coupling of service
interactions. These techniques minimize the cases where change to one part
of a system implies changes to other parts.
In a true SOA the integration solution should be able to invoke services
offered outside the enterprise by partners and should be extendable to
support future partners.
The Web services technologies have proven effective in many
business-to-business integrations, where their open standards basis and use
of simple, existing infrastructure and protocols makes them particularly
effective. Recent and emerging standards, such as WS-Security, add to the
sophistication of interaction that is possible when using Web services in this model.
There is no single data, business, or process model across, or beyond, the enterprise.
Although they are not a magic solution to this issue, the SOA principles define an approach that enables organizations to progressively expose functions across their business as services and to combine those services into processes. SOA encourages processes to be centrally managed and
explicitly defined and modelled. Over time, businesses that take this
approach will improve the consistency of their business and process models
and will leverage the use of business process modeling and automation
technology to more explicitly control and monitor their execution of processes.
Not all integration technologies work as well across a wide area network or
the Internet as they do across a local area network.
The Web services technologies support multiple protocols, so they can use
the simplest protocols available, such as HTTP when that offers an
advantage, or leverage other infrastructures such as WebSphere MQ when
that is more appropriate.
For these reasons, SOA and Web services are often seen together as the future direction for system integration.
When to use SOA:
When you feel your business process can be useful for others and you want to make some money out of it or for whatever reason, you publish it as a service and anyone who wishes to use your business process (now service) can consume it� it increases reusability. One very common example is, credit card verification service, many sites consume this service and validate users� credit cards.
Apart from this, in an organization, many platform exists and thousands business operations run on them. Now if there is any need to integrate one business operation with other, SOA is the way to go. You publish one business operation and consume it in other business operation.
There are many ways to implement SOA. One very popular way is through WebServices.