1 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall James A. Senn’s Information Technology, 3 rd Edition Chapter 12 Creating Web-Enabled Applications

2 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Objectives Describe the three principal forces behind the interest in creating Web-enabled applications in enterprises. Distinguish between the purposes of HTML and XML in Web-enabled applications. Explain how XML aids in creating interenterprise IT applications.

3 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Objectives (Continued) Identify the six advantages of XML. Explain the potential benefit of Web services to enterprises IT applications. Identify and describe the three tools that facilitate the user of Web services.

4 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Forces Behind Web-Enabled Systems Definition Web-enablement:The tendency of systems developers to incorporate features of the Internet in enterprise systems.

5 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Forces Behind Web-Enabled Systems Widespread Use of Browsers New computers shipped with Web browsers Large installed base of browser users Browsers appearing on other IT devices Intuitive features

6 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Forces Behind Web-Enabled Systems Widespread Use of Browsers (Continued)

7 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Forces Behind Web-Enabled Systems Widespread Use of Browsers (Continued) Flexibility –Plug-ins: Software programs that extend the capabilities of your Internet browser, giving it added features. Universal front-end application

8 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Forces Behind Web-Enabled Systems Legacy System Legacy System: Refers to the many mainframe, midrange, client/server or PC applications that are used to manage business functions.

9 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Forces Behind Web-Enabled Systems Interconnected Enterprises Interoperability: The perfect exchange of data and information in all forms (data, text, sound, and image, including animation) between the individual components of an application (hardware, software, network). Heterogeneous Applications: May be written in different programming languages, run on different types of computers, and use varying communications networks and transmission methods.

10 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Extensible Markup Language Definition Extensible Markup Language (XML): Developers can design their own customized markup languages for describing data.

11 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Extensible Markup Language Structure of XML

12 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Extensible Markup Language XML Advantages

13 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Extensible Markup Language Document Type Definition Document Type Definition (DTD): Defines the vocabulary (or standard) to make the data easily understandable and useable.

14 (c) 2004 Pearson Prentice Hall Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Extensible Markup Language Document Type Definition (DTD) (Continued)

15 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Extensible Markup Language Presentation Using XML Style Sheets Presentation Using XML Style Sheets –XML Stylesheet Language (XSL): Created by developers or publishers of XML data to manage the display and presentation of information in a document.

16 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Extensible Markup Language Processing XML

17 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Extensible Markup Language Processing XML (Continued)

18 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Web Services Definition Web Services: Modular Internet applications that perform a very specific function or task.

19 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Web Services Web Services Principle

20 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Web Services Simplified Object Access Protocol Simplified Object Access Protocol (SOAP): The protocol used by an application to invoke a Web service located on another computer.

21 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Web Services Simplified Object Access Protocol

22 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Web Services Web Services Description Language Web Services Description Language (WSDL): Describes the capabilities offered by a specific Web service as well as the protocols and formats the service uses.

23 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Web Services Web Services Description Language

24 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Web Services Universal Description, Discovery, and Integration Universal Description, Discovery, and Integration (UDDI): A worldwide directory for registering, finding, and using Web services. –Yellow Pages: Describe the services offered by UDDI. –Green Pages: Describe how an application can use the Web Services.

25 Senn, Information Technology, 3 rd Edition © 2004 Pearson Prentice Hall Web Services Universal Description, Discovery, and Integration (Continued)