Web services allow applications to share data and capabilities across various operating systems, platforms, and devices using standard web technologies like HTTP, XML, and SOAP. A web service is a programmable application accessible via standard web protocols that is self-contained, self-describing, and loosely coupled. The web services architecture includes communication channels, XML for data representation and exchange, WSDL for describing services, and UDDI for service discovery. Web services offer advantages like platform independence, use of open standards, and easy incorporation into existing XML messaging solutions.

1. WEB SERVICES EXPLAINED Sreerag Gopinath P.C, Roll No. 24, Semester VII, Computer Science & Engg., SJCET, Palai MICROSOFT’S .NET TECHNOLOGY – OBJECTIVES & ARCHITECTURE

2. How giants define Web Service XML Web services let applications share data , and -- more powerfully -- invoke capabilities from other applications without regard to how those applications were built , what operating system or platform they run on, and what devices are used to access them. An application that accepts requests from other systems across the Internet or an intranet, mediated by lightweight, vendor-neutral communications technologies.

3. Before Web Services

4. The Web service emerged as the solution for providing a standard way to retrieve data without proprietary software and hardware . A Web service cornerstone is its ability to transfer data from the provider to the consumer, or requester, using the ubiquitous HTTP protocol; the data format is XML . Formatting the data in XML greatly facilitates raw data's conversion into a renderable format. Extensible Stylesheet Language Transformations (XSLT) perform the transformation rather easily, without complex parsing programs. What is a Web Service ?

5. What is a Web Service? …contd

6. The Web Service Approach

7. Web Services Architecture Fundamental blocks of WSA model: Communication channel – SOAP Data Representation & Exchange Mechanism – XML Meta Language for Describing Services – WSDL (Web Services Definition Language) Directory Service – UDDI (Universal Description, Discovery, and Integration)

8. Characteristics of Web Services Self-contained Self-describing Modular Loosely coupled Dynamic discovery Published, located, and invoked across the web

9. Find-Bind-Execute Paradigm

10. Advantages of Web Services Web Service is a programmable application , accessible via standard Web protocols. Uses open, standard Web protocols like HTTP, XML and SOAP, and works through existing proxies and firewalls. Can take advantage of HTTP authentication . Encryption for free with SSL . Easy incorporation with existing XML messaging solutions. Takes advantage of XML messaging schemas and easy transition from XML RPC solutions. No conflict between proprietary component based solutions like CORBA and COM. Combines the best aspects of component-based development and the Web. Available to a variety of clients ( platform independent ).

11. References http://www.microsoft.com/webservice http://www.javaworld.com Developer IQ , June 2005 Professional .NET Framework , Kevin Hoffman, Jeff Gabriel et al., “ Apress” .

12. WEB SERVICES EXPLAINED MICROSOFT’S .NET TECHNOLOGY – OBJECTIVES & ARCHITECTURE - Sreerag Gopinath P.C