buttom up is first create class, generate methods and create a wsdl from this, top down is first create wsdl and than generate codes depend on this wsdl
A good way to write an introduction to WSDL tutorials is begin by explaining what WSDL stands for. Giving a brief explanation of what will be included in the tutorial is also a good way to introduce the subject matter.
Top down approach requires you to write your own WSDL and XSDs and then create service which follows that WSDL and XSDs. In bottom up approach you first write service code and then WSDL and XSDs. In MS world bottom up is very easy because WSDL and XSDs are generated for you by tools. The first approach is much harder because it has lesser support in tools and because developers are usually not skilled enough to write WSDL (especially with WS-Policies).
WSDL
XML (eXtensible Markup Language) is a set of rules for encoding documents. The rules could describe anything from the rules of HTML to various file formats. WSDL (Web Services Description Language) provides a model for describing web services. WSDL uses the XML to specify its rules.
1.Soap 2.wsdl 3.uddi
WSDL
W3c
In the US, computer code is broadly characterized as a literary work, and as such can be protected by copyright.
Jean-Marie Chauvet has written: 'Services Web avec SOAP, WSDL, UDDI, ebXML..'
The term Web services describes a standardized way of integrating web based applications using the XML, SOAP, WSDL and UDDI open standards over an internet protocol backbone.
A Web Service is a software system designed to support interoperable machine-to-machine interaction over a network. It has an interface described in a machine-processable format (specifically WSDL)