Summary System Analysis and Design Chapter 2

Chapter 2
 Technology architecture - computing hardware, network hardware, and system software employed
by organization
 Application architecture - information systems, subsystems, and supporting technology that
supports organization


Systems Analysis Activities
 Gather Detailed Information
 Interviews, questionnaires, documents, observing business processes, researching vendors, and
suggestions
 Define Requirements
 Use information gathered from users and documents to determine requirements for new system
 Functional requirements and non-functional requirements (user interface, performance, reliability,
security)
 Prioritize Requirements
 Talk to users to find out essential, important, vs. desires (non-essential)
 Develop User-Interface Dialogs
 Flow of interaction between user and system
 User interface is very important to help users understand, prototype can be developed for testing
 Evaluate Requirements with Users
 User involvement, feedback, adapt to changes


System requirements and FURPS
 System requirements
 Activities new system must perform, and limits new system must meet (functional +
nonfunctional)
 FURPS
Functional requirements
Usability requirements
Reliability requirements
Performance requirements
Security requirements

 Functional requirements
 The activities the system must perform to support the users’ work (Use cases)
 Nonfunctional requirements
 Required system characteristics other than the activities it must perform or support
 Usability requirements
 Requirements for operational characteristics related to users
 User interface, related work procedures, online help, and documentation
 Reliability requirements
 The requirements that describe system dependability

,  Performance requirements
 Requirements for operational characteristics related to measures of workload, such as output and
response time
 Security requirements
 Requirements for how access to the application is controlled and how data is protected in storage
and transmission




Additional Requirements Categories
 Design constraints
 Specific restrictions for hardware and software
 Implementation requirements
 Specific languages, tools, protocols, etc.
 Interface requirements
 Interface links to other systems
 Physical requirements
 Physical facilities and equipment constraints
 Supportability requirements
 Automatic updates and enhancement methods


Stakeholders
 Stakeholders
 Persons who have an interest in the successful implementation of the system
 Internal stakeholders
 Persons in organization who interact with system or have a significant interest in its operation or
success
 External stakeholders
 Persons outside organization’s control, influence who interact with system or have interest in
operation or success
 Operational stakeholders
 Persons who regularly interact with a system in the course of their jobs or lives
 Executive stakeholders
 Persons who don’t interact directly with the system but who either use information produced by
the system or have a significant financial or other interest in its operation and success (senior
managers, board of directors)
 Client
 A person or group that provides the funding for the system development project