The exchange infrastructure is SAPs new open-integration platform,
designed to handle the integration challenges that companies face as they
try to manage the heterogeneity of their systems not to mention
those of their partners and customers. With this new technology, SAP promotes
a flexible, message-based infrastructure, based on open standards such
as XML, to integrate a variety of components. As a result, it becomes
easier than ever to develop and implement large-scale business processes
that cut across various systems and technologies (often referred to as
an outside-in approach).
Of course, not all of your business processes
will require this kind of scope or complexity. Sometimes processes are
better suited to an inside-out approach that many SAP customers
have used for some time now where processes within a single
application drive processes in other components, and are integrated
with other systems via RFCs, XML messages, or SOAP, for example.
Take the scenarios in Figure 1.
For something like purchase requisition approvals, nearly all the processing
takes place via a single EBP system. The technology that drives this inside-out
process is the WebFlow engine, SAPs long-standing technology for
integrating workflow with the Web. In contrast, the materials master process
is more appropriate to an outside-in approach: data entry takes place
across many sites and end users, and requires multiple and often
different views maintained in a variety of components. The exchange
infrastructure includes a message-based Business Process Engine to help
drive these types of processes. With this approach, it is also easier
to keep the process running when one component is upgraded or even when
it is replaced by a component from a different vendor.
||Application-Based (Inside-Out) versus Message-Based
Although application-based and message-based
processes are quite different, many of the very same features are needed
for each. The exchange infrastructure will give you the flexibility to
choose the approach either the message-based (outside-in) or application-based
(inside out) that best matches your particular business scenario.1
If you are evaluating the exchange infrastructure
or want to extend the boundaries of the processes running in your mySAP
components right now, then this article is for you. Youll learn
about the collaboration capabilities currently available with WebFlow,
and preview some of the functionality that will be available in the Business
Process Engine when it is released later this year.
This article does not cover the
major new features that are under development for the Business Process
Engine, such as:
- Completely new mechanisms necessary for supporting a message-based
- The fresh new appearance of user interfaces for the different tools,
such as the process modeler and process monitor
So lets go through the WebFlow features
that are currently available for enabling inside-out process control,
listed in Figure 2.
||4.6C and up
||Interface using an open standard to trigger and
pass data between processes using XML messaging.
||An extension of 1.0, allowing more powerful synchronization capabilities.
||Commonly accepted protocol for invoking methods.
||Interface using an open standard to transfer process designs between
||4.0 and up
||Use HTTP to call dialog and background services and collect the
results. WSDL standard descriptions can be imported to configure the
||Current and Future WebFlow Features for Inside-Out Processes
Business Processes Are Already In Your System Whether
Youre Driving Them or Not!
If you are asking yourself, But do I even have business processes
in my system right now? the answer is certainly Yes.
For example, lets take an engineering
change request, where experts from both the business and technical
sides of a project team up with component suppliers to process requests
as quickly and reliably as possible. In a smooth-running company,
these processes will be automated and under control.
Whats the difference between
something like a basic exchange of messages and a business
process? Typically, business processes can be represented
by flow diagrams and involve deadline handling and audit trails.
Most important, a business process has a state. In order
to work out what to do next, a business process keeps track of where
it is i.e., what it has accomplished so far. Contrast this
with a simple message exchange where incoming messages spawn new
messages based on their content, irrespective of their history.
The bottom line is that if your business
processes do not work, your business does not work either. Getting
your processes to run faster, more reliably, and more inexpensively
while keeping them flexible is what it takes to have the competitive
edge. Driving the processes with an engine like WebFlow is far more
likely to enable you to reach this goal than simply relying on written
procedures or word of mouth.
The exchange infrastructure will
soon be able to handle outside-in scenarios, but for the time being
it is sufficient to handle processes using the inside-out approach.
Wf-XML Snaps Processes Together, Irrespective of the System or Software
that the Process Runs In
Wf-XML is an open interface from the Workflow Management Coalition (WfMC),
which any vendor is free to implement. Wf-XML Release 1.0 supports the
triggering and canceling of processes as well as the transfer of data
The newly released 1.1 Wf-XML standard
supports better synchronization between processes. Typically, several
business processes will run in parallel, independently of each other (which
saves time), but they have to synchronize at different checkpoints to
exchange data, or wait until another process has set up the prerequisites
that enable the first process to continue.
Enhancements made to SAP R/3 4.6C and up
include the ability to define rules for formatting the context data, and
rules to determine a partners URL and authentication data. These
rules are based on the data in the current process, so that one process
definition can deal with all possible partners involved.
As you can see in Figure 3, all
the capabilities needed for Wf-XML handling are taken care of in a comfortable
||Transmitting a Wf-XML Message via HTTP and the Step
BPML Business Process Modeling Language
BPML is an XML standard from the Business Process Management Initiative
(BPMI.org), which allows process flow definitions to be mapped to XML.
The Workflow Builder can export or import BPML documents to display them
graphically. In keeping with SAPs strategy of open interfaces, this
is a non-proprietary interface developed by BPMI.org.
BPML describes the process flow, but not
the individual activities that are executed in the process. These activities
will need to be described by something else, such as WSDL2
(see the next section). For more on BPML, please refer to the Web Application
Server 6.20 development news at www.sap.com/technology.
WebFlow Web Services
WebFlow Web service support was described in detail in the January 2002
issue of SAP Insider using the example of mobile messaging via
a remote Web service.3 The essence of WebFlows use of Web services
is that an activity within a process calls a remote resource over the
Internet or intranet. This service can pass results back to the process,
just as if the standard business method had been executed within the local
component. Dialog services are also supported, such as querying a companys
intranet whos who database to select a colleague for
a particular task.
It does not matter what language the Web
service was developed in whether its Java, Business Server
Pages, or Active Server Pages, to name just a few examples. There are
standards to describe these services the most prominent being WSDL
and Web sites that support catalogs of external services, such
as UDDI (www.UDDI.org).
In the SAP Web Application Server Release
6.20, simple WSDL service descriptions based on HTTP binding can be imported
directly into the WebFlow service catalog without the need for manual
Where Do We Stand Now?
WebFlow incorporates the open standards that are needed to reach across
the Internet, but are also needed to link to individual system components.
The Business Process Engine will support these same standards, too.
For more information on WebFlow technology,
For more on the exchange infrastructure and the Business Process Engine,
see the SAP white paper Exchange Infrastructure: Process-Centric
Collaboration at www.sap.com/solutions/technology/brochures.asp
and the articles on the exchange infrastructure in this issue of SAP
more information on the Integration Engine
and the Exchange Infrastructure, see the
white paper Exchange Infrastructure: Process-Centric Collaboration at www.sap.com/technology,
and the articles in this issue of SAP Insider.
2 WSDL is an
open standard that has been submitted to the World Wide Web Consortium
3 See Workflow Wizard: Accessing External Web Services from SAP WebFlow in
the January-March 2002 issue of SAP Insider, or in the Article
Alan Rickayzen is the Product Manager for WebFlow. He has been with SAP
since 1992 and in data processing since 1988. In 1995, he joined the SAP
Business Workflow group, performing development work as well as consulting
for various major US customers, and as a result amassed a good technical
knowledge of the product. In 1998, he moved to the area of workflow product
management. The author may be contacted at firstname.lastname@example.org.