Database Reference
In-Depth Information
• Request-Response
• Solicit-Response
• Notification
The One-way and Request-Response are synchronous communications and invoc-
ation, that is, Solicit-Response and Notification (or reply) are part of asynchronous
communication.
Web services provide interoperability and an ability to conduct simple interactions by
using standard protocols. However, systems integration achieved by using web ser-
vices doesn't provide process agility; it requires a standard way to create a process
and an ability to create an integration model. BPEL defines a model and syntax for
describing the behavior of a business process and interactions between the process
and its partners.
For many years, many software vendors tried to develop and standardize web ser-
vices and non-standard proprietary-based workflow for creating and managing busi-
ness processes. Some of the existing workflow tools and runtime engines are com-
plicated and fragmented.
For example, IBM and BEA (BEA is acquired by Oracle) tried to promote
Web Ser-
vices Flow Language
(
WSFL
) and
XLANG
workflow standards (by Microsoft) that
enabled you to create business services.
Currently, most of the software vendors accept Business Process Execution Lan-
guage (BPEL) as the standard for creating and managing business processes based
on the workflow. Some of the software vendors believe Business Process Modeling
Notation (BPMN) is the future of business process modeling instead of BPEL.
BPEL provides a standard way that facilitates combining multiple existing functions
into a new application and services from a number of distributed and autonomous
software components. BPEL addresses the problem of designing, defining, imple-
menting, and deploying composite services.
BPEL helps portability of business processes operating on different software to in-
teract with each other using a set of standard services. The basic underlying stand-
ard for BPEL is web services standards such as Web service Description Language
(WSDL) and Simple Object Access Protocol (SOAP). SOAP is an XML-based pro-
tocol for allowing applications to exchange data over HTTP(S).
