Designing System Interfaces, Controls and Security

CMT222/CMM321 SYSTEM ANALYSIS & DESIGN

CHAP 15 DESIGNING SYSTEM INTERFACES, CONTROLS AND SECURITY
Sharifah Mashita Syed Mohamad, PhD School of Computer Sciences Univer siti Sains Malaysia [e-mail]

Systems Analysis and Design in a Changing World, 5th Edition

OVERVIEW OF THE CHAPTER
 Differentiates between system interfaces and the user interface  Focuses on system interfaces, system outputs, and system controls that do not require much human interaction  Many system interfaces are electronic transmissions or paper outputs to external agents  System developers need to design and implement integrity and security controls to protect system and its data

Systems Analysis and Design in a Changing World, 5th Edition

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1. IDENTIFYING SYSTEM INTERFACES
 How do we identify interfaces of the system?  Recap: System vs. User interfaces
System interfaces
•I/O requiring minimal human interaction •Inputs captured automatically by some devices such as scanners. •Outputs – reports produced for external agents (other systems)

User interfaces

•I/O requiring human interaction •Customer places an order in a web-based system (Inputs) •Information displayed after the order is made (Outputs)

Systems Analysis and Design in a Changing World, 5th Edition

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1. IDENTIFYING SYSTEM INTERFACES
 System interfaces are broadly defined as inputs or outputs with minimal or no human intervention.
Highly automated input devices such as scanners Inputs that are from data in external databases Outputs to external databases Outputs with minimal HCI Outputs to other systems Real-time connections (both input and output)
Systems Analysis and Design in a Changing World, 5th Edition 4

FULL RANGE OF INPUTS AND OUTPUTS

Figure 15-1

Systems Analysis and Design in a Changing World, 5th Edition

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AN EXAMPLE OF COMMON SYSTEM-TOSYSTEM INTERFACE…..
 eXtensible Markup Language (XML)
Extension of HTML that embeds self-defined data