Web Services - Guide to Cloud Computing for Business and Technology Managers - page 171

8
Web Servic es
Web Services are new standards for creating and delivering cooperative
applications over the Internet. They allow applications to communicate irre-
spective of the platform or the operating system. By using Web Services,
developers can eliminate major porting and quality testing efforts, poten-
tially saving millions of dollars. They will radically change the way that
applications are built and deployed in future.
A developer can create an application out of reusable components. But
what good is it to have a large library of reusable components if nobody
knows that they exist, where they are located, and how to link to and com-
municate with such programmatic components? Web Services are stan-
dards for finding and integrating object components over the Internet. They
enable a development environment where it is no longer necessary to build
complete and monolithic applications for every project. Instead, the core
components can be combined from other standard components available on
the Web to build the complete applications that run as services to the core
applications.
Some of the past approaches for enabling program-to-program commu-
nications included combinations of program-to-program protocols such
as Remote Procedure Call (RPC) and Application Programming Interfaces
(APIs) coupled with architectures such as Common Object Model (COM),
the Distributed Common Object Model (DCOM), and the Common Object
Request Broker Architecture (CORBA). But, without a common underly-
ing network, common protocols for program-to-program communication,
and a common architecture to help applications to declare their availability
and services, it has proven difficult to implement cross platform program-
to-program communication between application modules. These previous
attempts to set up standards for accomplishing these objectives were not
very successful because
• They were not functionally rich enough and are difficult to maintain
as best of breed
• They were vendor specific as opposed to using open and cross
vendor standards
• They were too complex to deploy and use
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