1. Web-Based Systems: Initial Questions
What is a Web-Based System?
How is it build?
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2. What Is a Web-Based System?
“A software system based on technologies and standards of
the World Wide Web Consortium (W3C) that provides Web
specific resources such as content and services through a user
interface, the Web browser” (Kappel et al.)
Therefore, this definition excludes:
Web sites without software components (e.g. static HTML
pages)
Web services
Web-Based System = Web Application
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3. Categories of Web-Based Systems
Ubiquitous
Semantic-Web
COMPLEXITY
Social-Web
Collaborative
Workflow-
Based
Portal-
Transactional Oriented
Interactive
Document-
Centric
DEVELOPMENT HISTORY
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4. Characteristics of Web-Based Systems
Network intensiveness
Internet
Intranet
Global reach and Unpredictability
Who are the users?
Usage patterns
Backgrounds: language, culture, age, education, ...
How many users?
Potential / Occasional / Frequent users
Concurrency: average, peaks
Competition and Differentiation
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5. Characteristics of Web-Based Systems
Space / Time
Internationalization
Location-aware services
Availability
Hypertext
No-linearity
Navigation
Content-driven
Document-centric
Multimedia
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6. Characteristics of Web-Based Systems
Look and feel
Usability
Accessibility
Aesthetics
Continuous Evolution
Security
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8. Web Engineering
“Web Engineering is the application of systematic and
quantifiable approaches (concepts, methods, techniques,
tools) to cost-effective requirements analysis, design,
implementation, testing, operation, and maintenance of high-
quality Web applications”. (Kappel et al.)
A Web Engineering Process must accommodate
Incremental delivery
Frequent changes
Short timeline
Therefore,
An incremental process model should be used in virtually all
situations (e.g. RUP)
An agile process model is appropriate in many situations
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9. The Web Engineering Process
Acceptance test Coding
Customer’sfeedback Component testing
Release
Design models
Analysis models
Umbrella activites
Business analysis
Vision document Change management
Iteration plan Quality assurance
Risk management
Project management
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10. Web Engineering: Techniques and Tools
Communication among participants
Formal/informal meetings, documentation, e-mail, demos,
project management tools, etc.
Requirements elicitation
Communication with stakeholders, vision documents, use
cases, CASE tools, etc.
Modeling
UML artifacts, design patterns, CASE tools, etc.
Construction
Programming techniques, code editors, compilers, version
management, installers, IDE, open source code, etc.
Testing
Strategies, tools, etc.
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11. Web Engineering: The People
Domain experts
Content developers/providers
Web editors
Web engineers: We!
Support team
System evolution: patches, adaptations, improvements
Administrator (webmaster)
Statistics, tuning, security, etc
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12. References
R. G. Pressman, D. Lowe: Web Engineering. A Practitioner’s
Approach. McGraw Hill, 2008. Chapters 1-2.
KAPPEL, Gerti et al: Web Engineering. Wiley, 2006. Chapter 1.
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