Industry heavyweights Microsoft Corp, IBM Corp. BEA Systems Inc. in August unleashed a trio of proposed Web services standards that address several unmet needs of the nascent services-oriented application model.
With these standards, the companies are looking to solidify workflow and business process execution as well as transaction integrity and coordination. The proposed specifications are intended to instruct developers on how to define, create, and connect multiple business processes in a Web services environment both across their enterprise and with their partners and customers.
Primary among the new proposals is the awkwardly named BPEL4WS (business process execution language for Web services), which represents the marriage of two rival standards, Web services flow language (WSFL) from IBM and XLang from Microsoft. An executable language, BPEL4WS is designed to ensure that differing business processes can understand each other in a Web services environment.
“Web Services standards today allow you to have application-to-application interoperability, but how do you coordinate a set of Web services in order to work towards a common end? You need to do it through a business process language that is executable, and that’s what we have here,” said John Gardner, director of Web services marketing for BEA Systems.
Many industry observers had expected WSFL to subsume XLang as a standard. Officials from all three companies believe they have successfully integrated features and capabilities of both specifications without losing key capabilities, and have added a few new ones particularly in the area of workflow.
“One of the main problems to solve here is B2B workflow, which is still too hard given all these heterogeneous environments. We think that Web services is a great way to connect them all together,” said Steve Van Roekel, Redmond, Wash.-based Microsoft’s director of Web services technical marketing.
The other proposed standards include one for Web services transactions, dubbed WS-Transaction, and one for Web services coordination, called WS-Coordination.
The former deals with what experts refer to as non-repudiation and will help to ensure the integrity of Web services transactions, making sure that a transaction happens only once and if a mistake occurs it is compensated for automatically. This becomes particularly important for transactions involving finances, such as purchase orders. Clearly, there is a need to make sure that a purchase order, and a corresponding payment, goes through once and only once.
Through WS-Transaction companies can monitor the success or failure of each specific, coordinated activity in a given business process. It is designed to provide them with a flexible transaction protocol to ensure more consistent and reliable operations across distributed organizations in a Web services environment.
WS-Coordination drills down further into the transaction, providing a standard way for making sure that many simultaneous transactions execute correctly from one system to another, regardless of platform. It is intended to give developers a way to manage their operations as they relate to a specific business activity. A process may involve a number of Web services working together to provide a common solution.
WS-Coordination supplies the structure under which coordination can take place. It can also assist developers control operations that span interoperable Web services, officials from the companies explained.
The three proposals join an alphabet soup of other Web services standards, including the now mainstream SOAP, XML, UDDI, and WSDL. None of these new specs address security, however, which users still consider to be the largest stumbling block when it comes to Web services.
To that end, Microsoft and IBM also developed the WS-Security specification, which in late June was turned over to Organization for the Advancement of Structure Information Standards (OASIS), which promptly formed a technical committee focusing on WS-Security, and intended to give vendors a crack at the immature specification.
OASIS also absorbed the UDDI.org group that was building UDDI technology for dynamically discovering and consuming published Web services.
UDDI, in conjunction with XML, SOAP, and WSDL, form the core set of base protocols for Web services that vendors such as Sun, Oracle, Microsoft, IBM, and BEA have all agreed to support.
The three companies intend to spend the next “two to four months” talking to users about the proposed standards to get their feedback on what they think of them and how they might be refined.
They will also spend that time trying to garner support from developers for them. Presently, only Siebel Systems has thrown its full weight behind it, although officials from IBM, Microsoft, and BEA said they expect at least a handful more over the next week.
Once that is done, they will then formally propose them to the key standards bodies including OASIS, W3C, and WS-I.
