Perhaps you're already sated by the current stack of Web services standards, but be prepared, more are coming and within a few years the intention is that they be piled high like a Dagwood sandwich.
At last week's SHARE conference in Boston, two of IBM's standards gurus gave an update on the current state of Web services, informing the audience that numerous quality of service specifications should soon be working their way into official standards bodies.
Most people these days are familiar with the basic set of Web services: XML for encoding, SOAP for messaging, WSDL for description and UDDI for discovery. They form the foundation of what is envisioned as the full Web services stack. The top of the stack also has its core standard in Business Process Execution Language (BPEL).
It's the space in between where the next few years of standards will be focused, according to Kelvin Lawrence, CTO of emerging Internet software standards for IBM.
"We know what it takes to perform transactions and what quality of service is expected in the traditional computing world," he said. "The same kinds of things are going to be needed in the Web services world."
The first of those quality of service standards was WS-Security, but important subsets of the security are about to become to enter standards bodies. WS-Trust, which establishes an XML syntax for managing credentials across secure domains, will soon be submitted to OASIS, Lawrence said.
Quickly on its heels, WS-Secure Conversation should become an official project of that standards body. That specification will allow people to enter into multiple message conversations without having to go back to square one on the security checklist with each new message.
In another year or so Lawrence expects WS-Federation to hit the standards main stage. That standard will provide security across multiple domains that do not share a single identity manager.
Chris Ferris, senior technical staff member with IBM's emerging technology group, noted that WS-Addressing, which enables asynchronous messaging and establishes a unique ID for each message, could emerge as an official standard from the W3C before the end of the year.
One of the keys for quality of service, WS-Reliable Messaging, is about a year off from becoming a ratified standard, according to Ferris. It will follow the IBM MQ model of guaranteed one-time delivery, establish a message's place within a given sequence and provide fault notification to the involved parties.
"This is one of the fundamental specifications the world has been waiting for," Ferris said.
WS-Transactions, which establishes the two-phase commits necessary for processing transactions in the mainframe world, should "start its standards life this year," according to Lawrence.
It will be broken down into three components: WS-Coordination, WS-AtomicTransaction and WS-BusinessActivity. WS-Coordination will define a framework for deploying protocol specifications. WS-AtomicTransaction will establish short duration transaction models while WS-BusinessActivity will tackle longer duration transaction models.
Lawrence stressed that the idea behind all of the Web services standards will be that they can be mixed and matched as needed. WS-Policy will be an overarching framework designed to encapsulate exactly what the quality of service requirements, certificates and encryption standards are for a given service.
"It extends the WSDL and sets up the parameters for automatic compliance," Lawrence said. "Theoretically you should be able to got to a service and work with it without any human interaction. We're anticipating it's going into standards body any day now."