Zusammenfassung der Ressource
System Life Cycle
- Definition
- Feasibility
Study
- Also Known as the Feasibility
stage.
- Initial look at the existing system
to see how it can be improved.
- If possible it must meet needs and
requirements of the end users:
- The analyst should also consider
why a new system is required.
- For project to continue, the new
system must also be viable in
terms of hardware and software
choices, budget and time scale.
- 1st
- Investigation &
Analysis
- Feasibility
Stage
- Requirements
Specification
- 2nd
- Follows the definition of the problem and must
be fully completed before moving on to the
design stage.
- During this stages methods
can be used to collect data:
- Interviews
- Meetings
- Document Analysis
- Questionnaires
- Observation
- Results of the investigation are analysed to gain
full understanding of all the problems of the
current system.
- The user requirements are defined and agreed with the client, these are
constantly referred to during the development of the new system and
form the basis of the rest of the system life cycle.
- Design
- Requirements
Specification
- Design
- 3rd
- This stage cannot be started until the 'Investigation
and analysis' has be completed. also the
implementation stage cannot start until this stage is
completed.
- The objectives defined in the investigation and
analysis stage are followed.
- Methods and formats of data capture what
are designed:
- Input
- Output
- Structure of data
- Processing and
validation routines
- Queries
- Reports
- Project plan is developed taking
into account the client-defined
deadline for the installation of the
system.
- Implementation
- Design
- Completed
System
- 4th
- Also known as the
'Development Stage'
- This stage is about taking the
design forward and putting it
into practice to build the
system.
- A decision about the software strategy,
based on budget constraints set by the
client, is made.
- Coding, Macros and Queries are created with backup
and storage of data being considered.
- Testing
- Completed
System &
Test Plans
- Working
System &
Test Logs
- Testing follows a test plan, with results being
recorded.
- Ensures that the system is free of
bugs/errors and meets the defined user
requirements.
- if a test fails to provide
the expected result then
corrective action is taken
before a retest.
- 5th
- Installation
- Working
System
- Completed
& Installed
System
- 6th
- The system is installed for the client.
- The installation strategy is chosen and training of
the end users is carried out at this stage.
- Methods of Installation:
- Parrallel
- Phased
- Pilot
- Direct
- Doccumentation
- 7th
- Documents that are created and
passed to the user of the system
- Test plans
- Data and Logs
- User Manuals
- Version and security details
- Program Specifications
- Evaluation & Maintenance
- Evaluation
- May form the basis on which the decision is taken
to begin the system life cycle again.
- Demonstrates the iterative nature of the system life cycle.
- The solution should be evaluated once it has be
implemented with maintenance.
- Maintenance
- The process of ensuring that a system continues
to meet the needs of its users.
- 8th
- The stages that need to be completed to create a new or modified
system. Referred to as a cycle as, after time, the process will have to be
repeated.