Office applications Toolkit

Magical Web service tour

Tags:
B2B,
SOAP,
HTTP,
XML

Bain McKay Builder.com

Published: 13 Jun 2002 16:48 BST

WSDL-XML documents contain a Header section for namespaces, a Services schema defining element types, a Messages section for element Request and Response mapping, a PortType section that defines endpoints for services, a Binding definition for Input and Output parameters, and a Security declaration section. A picture is worth a thousand words, so refer to Figure C for the WSDL-XML document structure.

Figure C

WSDL XML document structure

Where's the SOAP?
SOAP is an XML derivative used by Web services to marshal transaction information into XML elements of the Transaction Request at the client side, bind it to the Transport protocol, and unmarshal it at the supplier side. It then reverses that process to pass results back to the client application through the Transaction Response. SOAP is protocol independent so it can bind to supported transport protocols like HTTP, HTTPS, and SMTP. For B2B, SMTP provides an appropriate asynchronous transport. Figure D gives a glimpse of a SOAP transaction's flow.

Figure D

SOAP transaction

What role does ebXML play?
Electronic Business using Extensible Markup Language (ebXML) is the counterpart to EDI in the XML world, providing extensibility, flexibility, and schema services as a common business exchange platform for trading partners. With ebXML, business contracts can include rules of engagement, process schemas, and namespace. EbXML uses SOAP headers to pass routing information.

What is transacted with Web services?
Web services can support any B2B transactions as well as a host of new transactions:

Corporations can support automated B2B transactions in supply chain and customer value chain applications.
Software can leverage Web services to automatically research and recommend best product offerings on a global scale in a productive manner heretofore unachievable on a manual or automated basis.
Just-in-time inventory management can reach commodity status for small- and medium-size business usage.
Web services providers will be in demand as third-party services brokers who facilitate inter-business flow through UDDI Directory Services.
Information and knowledge providers can provide research repositories through semantic interfaces like taxonomies and ontologies.

Web services are waiting to take you away
Web services can take business automation to the next level of productivity and affordability through open standards. New services and products coming to market will facilitate automated inter-business transactions and highly productive knowledge and information research offerings. Enterprise application developers and product providers who don't take advantage of J2EE Web services will be left behind in this architectural shift as these new, more productive technologies replace sunset application development architectures made popular over the past few years.

Have your say instantly in the Tech Update forum.

Find out what's where in the new Tech Update with our Guided Tour.

Let the editors know what you think in the Mailroom.

Go to section: