WFXML

This document represents a workflow protocol that aims for interoperable, reliable, and practical interactions between services using HTTP protocol. This protocol is based on Wf-XML and extended for the sake of enterprise EDI applications.

Wf-XML defines more precise interfaces and data model than WfMC interface4, using URI to identify a resource that enables easy inquiries to a resource. Wf-XML provides the interfaces to search for process instances of each process definition in addition to the interface to create and terminate a process instance. We developed a practical enterprise EDI system using Wf-XML (to be exact, we used SWAP, origin of Wf-XML). As a result, Wf-XML is proved to be useful for developing EDI systems. However, we need to add some tags and interfaces to Wf-XML because Wf-XML falls short of some essential functions for EDI systems, that is, asynchronous messaging and multiple messaging. Enterprise interoperability will not be promoted if each system needs to add or modify a protocol respectively.

This document represents a specification for a language based on the eXtensible Markup Language (XML) [1], designed to model the data transfer requirements set forth in the Workflow Management Coalition (WfMC)’s Interoperability Abstract specification [1]. This language will be used as the basis for concrete implementations of the functionality described in the Interoperability Abstract supporting the WfMC’s Interface 4, as defined by the Workflow Reference Model [2].

ASAP offers a way to start an instance of an asynchronous web service (AWS), monitor it, control it, and be notified when it is complete. This service instance can perform just about anything for any purpose. The key aspect is that the service instance is something that one would like to start remotely, and it may take a long time to run to completion. Shortlived services could be invoked synchronously with SOAP and one would simply wait for completion, but because these process instances could last anywhere from a few minutes to a few months, they must be invoked asynchronously.

Wf-XML defines more precise interfaces and data model than WfMC interface4, using URI to identify a resource that enables easy inquiries to a resource. Wf-XML provides the interfaces to search for process instances of each process definition in addition to the interface to create and terminate a process instance. We developed a practical enterprise EDI system using Wf-XML (to be exact, we used SWAP, origin of Wf-XML). As a result, Wf-XML is proved to be useful for developing EDI systems. However, we need to add some tags and interfaces to Wf-XML because Wf-XML falls short of some essential functions for EDI systems, that is, asynchronous messaging and multiple messaging. Enterprise interoperability will not be promoted if each system needs to add or modify a protocol respectively.