Technology > More about BPEL
More about BPEL
Enterprise Application Integration
Most organizations have a highly disparate application infrastructure
comprising a variety of applications from multiple vendors, running on
different platforms, and created with completely different technologies.
Traditional enterprise application integration (EAI) products have emerged in
the last decade to tackle these integration challenges.
Over the last few years, many organizations have made significant investments
in these EAI solutions. As a result, business integrations in the EAI space
tend to be locked into a single vendor and the integration components are
tightly coupled. The cost of maintaining these proprietary integration links is
a significant burden. Specialized skills are required, exacerbating the cost
and stability concerns. Furthermore, ripping-and-replacing existing EAI
solutions is not a plausible alternative for an organization protecting massive
investments in EAI.
BPEL, which stands for Business Process Execution Language, addresses
all these problems by delivering a standards-based, platform-neutral solution.
BPEL is an industry-standard, XML-based workflow definition language that
allows businesses to describe business processes that are connected via web
BPEL provides an XML-based grammar for describing the logic to control and
coordinate Web services participating in a process flow. This grammar can be
interpreted and executed by a BPEL orchestration engine. The engine coordinates
all of the activities in the process, and controls the system's corrective
activities when exceptions occur. BPEL builds on and extends XML and Web
Services specifications.The loosely coupled BPEL process eliminates vendor
lock-in, reduces integration costs, and provides interoperability; it also adds
a sophisticated layer of security, exception management, and logging. Most
important, companies can leverage their existing infrastructure, service-enable
it, and orchestrate it using BPEL.
The BPEL standard does not address human involvement in business processes. As
a result, BPEL compliant products, such as Oracle BPEL Server, IBM Websphere
and Microsoft BizTalk, are primarily focussed on composing business processes
that integrate web services and legacy applications. It is true that all of
these products have some form of human workflow extensions, but these are
limited in functionality and cover only a small set of scenarios.
In August 2005, IBM and SAP released a whitepaper that addresses
the fact that human interactions are not covered by BPEL and proposes a
BPEL extension called BPEL4PEOPLE. The paper describes business scenarios where
users are involved in business processes and defines appropriate extensions to
BPEL to address these.
However, no formal specification has been released so far and it remains to be
seen if this initiative will be supported. It is also not part of the
latest draft of BPEL 2.0.