Lecturer: Prof. Dr. Gustaf Neumann

Description

This course covers advanced concepts that todays Web engineers need to be aware of. Those concepts include advanced data formats based on XML, techniques to query and process data in those formats, and techniques to use the data formats in Web applications. We discuss the importance of meta-data and present approaches to define Web services. The data formats introduced in the first part of the course provide the basis for higher level website engineering, leading to advanced topics like the "Semantic Web" and "plug-and-play electronic markets" that are subject to ongoing research today.

After the introduction to Web data formats this course focusses on the architecture of Web based information systems, addressing primarily server issues. We discuss caching mechanisms used in the Web and how a Web engineer can influence those. Then we describe the basic approaches to server programming in general (iterative and concurrent servers), and the impact of those server-related issues on application development. In the next units Web server extension mechanisms are introduced which allow us to provide application semantics. Since HTTP is a stateless protocol by design, handling of sessions has to be carefully planned and implemented by the Web engineer.

Today's Web applications have to take scalability into account. The next unit of this course introduces scalable systems that are used at some of the most busy sites in the Web. We describe how these systems are designed and how they can provide efficiency even under high load.

Successful Web sites are much more than simply a collection of Web pages and a few programs. Today's Web portals provide a high degree of personalization, they support collaboration to a large extent, and they contain content management facilities to ease maintenance and to improve flexibility. The last unit of this course provides a short introduction to the topic of portal development and discusses two prominent open source systems in this area.

Outline

1. Internet data formats
   1.1 Short introduction into XML basics
   1.2 Definition of structure and content: XML schema
   1.3 Querying XML data structures: X-Pointer
   1.4 Transformation of XML documents: XSLT
   1.5 Modification of XML documents: Document Object Model
   1.6 Event based parsing of XML documents: SAX
2. XML applications
   2.1 Providing precise information about data (meta data) in the Web: RDF
   2.2 Direct program-to-program communication in the Web: SOAP
   2.3 Languages for Web services: WSDL and UDDI
3. Web-based information systems
   3.1 Caching in the Web
   3.2 Server architectures
   3.3 Programming approaches (CGI, servlets, active server pages, application server)
   3.4 Session and state handling
   3.5 Hidden form fields, url encodings, cookies
   3.6 High performance Web server with database access (AOL server)
   3.7 Web content management systems (Zope and OpenACS)

Learning Objectives

The goal of this course is to provide students with a deeper understanding of Web engineering. Students will learn the most important concepts and fundamental technologies which are the basis both for real-world Web applications and for research in this field.

Method of teaching

This course is a hypermedia course (type 2). The lessons are available as hypertext with links connecting text, graphics and external information sources. Each lesson contains three parts: (1) Systematic and stepwise presentation of the concepts in the form of guided learning (instructional learning), (2) exercises based on additional on-line materials in the form of exploratory learning, and (3) an assignment in the form of "homework" that the student will solve and submit by e-mail. Solutions are graded.

Requirements

Prerequisite for this course is passing the MBI courses "Website Engineering Fundamentals", "Introduction to Computer Science", and "Introduction to Programming" (or equivalent programming knowledge). Students should have Windows 2000 and/or Linux installed on their computers because practical programming examples are provided, wherever appropriate, based on software which is freely available for those systems.

Credits

5.0 credit points