WS-I Rearchitects Basic Profile
Officials at the Wakefield, Mass., organization, which is focused on ensuring interoperability in Web services messaging, said Final Material status means the interoperability profiles have been formally approved by WS-I membership, which consists of more than 170 companies.
Chris Ferris, chair of the WS-I Basic Profile Working Group and a senior technical staff member at IBM, said the WS-I took its Basic Profile 1.0 and rearchitected it to place all binding-specific envelope serialization requirements into a separate profile, the Simple SOAP (Simple Object Access Protocol) Binding Profile 1.0.
"We found it necessary to rearchitect the Basic Profile because we wanted to separate out binding constraints into their own profile," Ferris said.
The Basic Profile 1.1 is an upgrade over Basic Profile 1.0 and represents a series of specifications that describe how to deliver interoperable Web services. Version 1.1 of the profile includes enhancements and refinements over the 1.0 release of the profile.
The new WS-I profiles show that "Web services are finally growing up," said Ronald Schmelzer, an analyst with ZapThink LLC, of Waltham, Mass. "We have seen that companies have seemed to be hesitant to implement Web services and SOAs [service-oriented architectures] on a widespread basis until some of the major roadblocks, such as standards definition, have been cleared out of the way. Also, they are looking for signs of adoption by their customers, partners and software vendors. Now that the WS-I has taken the final step with their Basic Profile, they have eliminated one of the potential stumbling blocks, namely that of standards convergence."
Meanwhile, Ferris said Web services that use attachments can be tested for WS-I conformance with a combination of Basic Profile 1.1 and Attachments Profile 1.0, while Web services that do not use attachments can be tested for conformance with a combination of Basic Profile 1.1 and Simple SOAP Binding Profile 1.0.
The Simple SOAP Binding Profile governs the use of the SOAP 1.1 messaging envelope, which is the XML structure for transmitting messages. Meanwhile, SOAP Messages with Attachments defines a Multipurpose Internet Mail Extensions (MIME) mechanism for packaging attachments with SOAP messages, Ferris said.
"In the process of finalizing the Basic Profile, it became apparent to a lot of the SOAP community that the Basic Profile did not cover attachments," Ferris said. "But there were things that allowed for the support of attachments, and there were some interoperability concerns with the way some vendors had gone about supporting SOAP with attachments."
Ferris said the attachments profile describes a structure for sending SOAP messages along with attachments that can vary in size. One reason for doing the additional content as an attachment could be the size of the attachment, he said. For instance a medical imaging attachment sent with a Web services message could be a large file. The attachments profile enables large binary files to be processed separately from the Web services transaction.
"On the attachments part of the story, companies realize that in order to gain the benefits of interoperability, proprietary binary protocols and formats simply wont cut it," Schmelzer said. "Thats the whole point of XML and Web servicesstandardizing the interfaces between systems and companies. However, the big downside here is that XML-based Web services are very inefficient. As such, thats why were seeing the emergence of companies like DataPower [Inc.] that are focusing on the performance angle of Web services and SOA, in effect reducing the risk of implementing Web services. Without this reduction of risk, adoption of Web services can be slowed."
Going forward, the WS-I will be working to deliver sample applications and testing tools for Basic Profile 1.1, Attachments Profile 1.0 and Simple SOAP Binding Profile 1.0, Ferris said.
Meanwhile, the WS-I recently started a new working group, the XML Schema Work Plan Working Group, which will look at interoperability issues relating to the use of XML Schema.