Work Flow and Collaboration


Web Services are atomic and stateless. This means that each interaction has to stand on its own. You make a Web Service request; you receive a reply, either synchronously or asynchronously; and you're done. That is, you're done as far as the Web Service is concerned.

But that's not how it is in business. Almost everything we do is part of a longer-duration transaction. As we discussed in Chapter 8, we have longduration business transactions that last from hours to years. For example, a purchase order is a transaction that may take hours to days, or even weeks, just to research and obtain quotes and approval, and it may be weeks or months until the order is completely satisfied (i.e., received and paid for).

Another set of standards has grown up along with Web Services to deal with this. As with some of the other standards, there was a period when many standards were created and proposed, but the industry has settled on one (at least for now). The standards considered, but subsequently dropped, included business process specification schema (BPSS) from ebXML, XLANG from Microsoft, WSFL from IBM, and BMPL from the Business Process Management Initiative.

The standards currently used are business process execution language for Web Services (BPEL4WS) and Web Service choreography interface (WSCI). BPEL4WS is a joint proposal from IBM, Microsoft, and BEA. BPEL4WS creates a shared stateful context for a number of partners to cooperate on completing a long-duration business transaction. WSCI is from Sun, SAP, BEA, and Intalio.

Work Flow

Historically, work flow was the documentation of the sequence of steps that manual forms went through as they were routed from person to person within an organization. Many work flow initiatives still follow this basic paradigm. Work flow associated with document imaging followed this basic paradigm, but by scanning the paper forms and letters, the organization was able to route the paper more rapidly, including to remote locations, and documents were never lost. Over time organizations gradually phased out the serial approval processes that were a holdover from paper-based days, and they performed more work in parallel.

At the core of all work flow systems are templates that describe users, work queues, and the routing that a particular type of transaction is meant to take. More sophisticated, and high volume, work flow systems allow work to be routed to abstract queues and then assigned to individuals based on their current workload and other considerations.

Orchestration and Choreography

Orchestration and choreography, which are used almost interchangeably, are terms for the level at which the templates for the work flow are created. The difference between orchestration or choreography and work flow is that the former is meant to be more proactive. That is, an orchestrated environment is meant to anticipate exceptions and unusual routing of work flow and have resources ready to address them.

In the Web Services world, BizTalk is Microsoft's orchestration environment; a WSCI equivalent is SunOne's WSCI editor.

Collaboration

Collaboration comes in two flavors: serial collaboration and simultaneous collaboration. For the most part, serial collaboration is just the participation in the work flow coordination of tasks that was laid out in the orchestration of a multicompany process.

Simultaneous collaboration involves having multiple people interact on the same work products at the same time. In the trivial case it is electronic whiteboarding. (I suppose the truly trivial, and often most effective, case is old-fashioned whiteboarding.) More sophisticated environments exist, however, such as those in which many engineers can modify the design of a three-dimensional part at the same time, referencing the same model.

So far none of the Web Services has addressed simultaneous collaboration.




Semantics in Business Systems(c) The Savvy Manager's Guide
Semantics in Business Systems: The Savvy Managers Guide (The Savvy Managers Guides)
ISBN: 1558609172
EAN: 2147483647
Year: 2005
Pages: 184
Authors: Dave McComb

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