This set of topics provide information about the service integration
technologies.
Why and when to perform this task
Service integration is implemented as a group of messaging engines
running in application servers (usually one engine to one server) in a cell.
Service
integration is a complete JMS v1.1 provider implementation (not just an API
but a working messaging system. The JMS provider is a pure Java implementation
that runs within the application server's JVM process. For persistent messaging,
WebSphere Application Server also requires a JDBC compliant database such
as DB2.
As a result, JMS messaging is built into WebSphere Application
Server and is easily available to any J2EE application deployed in WebSphere
Application Server.
Why use a service integration bus?
- To connect any kind of application to any other kind of application. This
is the traditional WebSphere MQ scenario, where different applications written
in different languages are running on different operating systems and you
want them all to be able to communicate with each other.
- TOo connect J2EE apps running in WAS servers. What's changed in the last
few years is that many of our customers are converting everything to J2EE
applications deployed in WebSphere Application Server so they do not have
to support every platform, only WebSphere Application Server. WebSphere Application
Server Version 5 enabled this with its Embedded Messaging feature, however this is
now better addressed with a service integration bus. For the situation where
many WebSphere Application Server applications are communicating, and you
also need to communicate with other non-WebSphere Application Server applications,
you must still use WebSphere MQ as the messaging system.
Architectures you can use for interoperating WebSphere Application Server
and WebSphere MQ are WebSphere MQ as an external JMS messaging provider, WebSphere
MQ links, and WebSphere MQ servers.
What are the benefits of service
integration bus?
- Secure externalizing of existing applications: You can use the bus to
expose existing applications as Web services, for use by any Web service-enabled
tool, regardless of the implementation details. This enables applications
or Web services deployed on a server deep inside an enterprise to be made
available as Web services on the Internet to customers, suppliers, and business
partners. Security options mean that this access can be tightly controlled.
- Return on investment: Business partners can reuse an existing process
that you make available as a Web service using the bus. This gives great scope
for the reuse of existing assets.
- Protocol transformation: The bus provides support for exposing an existing
service implemented in one protocol (for example, SOAP/JMS), as something
entirely different from clients (for example, SOAP/HTTP). This function is
invaluable for ensuring smooth interoperability between businesses that may
implement varying Web services protocols in their business applications.
- Messaging benefits: The fact that the bus is built on top of the Java
Messaging Service (JMS) delivered in WebSphere Application Server means that
it is able to expose messaging artifacts, such as queues and topics, as Web
services. It also provides advanced options for asynchronous communication,
prioritized message delivery, and quality of service (message persistence).
For more information about what is provided by service integration
within WebSphere Application Server, see the following topics: