Topic 1 System Fundamentals Flashcards
What are the stages of software life cycle
1) Planning and analysis
2) Design
3) Development
4) Evaluation
Why might a new system be created? Name 4.
to minimize costs
To increase productivity or quality of system
To reduce errors or flaws of the existing system
Old system may no longer be suitable for its original purpose
A computer system includes hardware, software, and the people working with it
True or False
True
Potential organisational issues in planning a new system. Name 4.
lack of attention to organisational issues, such as organisation culture
lack of guiding business strategies
Lack of stakeholder or end-user participation
Lack of attention to required training
What is a feasibility report
An evaluation of the potential of a project based on various various TELOS (technical, economical, legal, operational, schedule) criteria.
What does the operational feasibility seek to answer
Whether the existing organisational practices are sufficient to support the maintenance and operation of the new system
What does the schedule feasibility seek to answer
How long the end-users will have to wait for the new system
Define change management
Involves various parameters and is a process of shifting individuals, teams, departments from the present state to the desired state
Define legacy system
An old technology, hardware, or computer system
Often plays an important role in an organisation
Why don’t organisations just upgrade legacy systems to modern ones?
The data present in legacy systems may be incompatible with newer formats
Its applications may not be able to be upgraded
Define business merger
Combining of two or more business entities
Four strategies for successful integration during business mergers and its implications
1) Keep both information systems, and develop them to have the same functionality (high maintenance cost)
2) Replace both systems with a new one (increased initial costs)
3) Select the best information systems from each company and combine them (hard for employees to work with info systems from a diff company)
4) Keep one information system and drop the other (policy problems)
Define software incompatibility
Situation where different software entities or systems cannot operate satisfactorily on the same computer or on a network of computers.
Locally hosted system vs remotely hosted system (When is which most appropriate)
Locally hosted systems are appropriate for larger and complex systems
Remotely hosted systems are appropriate where there is no necessary hardware equipment in place or when the organisation wants to outsource responsibilities for maintenance, support, backups, and security.
Define SaaS (Software as a service)
Delivery method that allows software and data to be hosted and managed centrally on a remote data centre.
Features of SaaS. Name 2.
users pay a subscription fee for SaaS to access the services
SaaS solutions reside on cloud and therefore need a web browser and an internet connection to access it
Advantages of SaaS. Name and explain the three
1) less expensive (low investment)
2)provides a scalable solution as company can adjust their monthly SaaS subscription based on need
3) Safe option as data and applications reside on cloud of the SaaS provider
Disadvantages of Saas. Name and explain the two
Possibility of data loss if the SaaS provider goes out of business
performance using SaaS is slower than locally hosted systems because the system can be hosted in a distant data centre
What is a changeover
A process of putting the new system online and retiring the old one
Name the 4 types of changeovers
Parallel
Direct
Pilot
Phased
Explain parallel changeover, 4 things
both systems work in parallel for a short period of time.
very popular because of the limited risk.
When the company is satisfied with the output of the new system, the old system can be terminated.
Running two different systems simultaneously means extra costs and workload
Explain direct changeover, 4 things
very risky since the company plugs in the new system and unplugs the old one at the same time.
dangers associated with this method if the new system does not function as expected.
This method is preferred when the system is not critical.
all users need to be trained appropriately before the switch takes place
Explain pilot changeover, 5 things
mostly used in large organizations that have multiple sites
new system is introduced in one of the sites and extended to other sites over time
risk of this method is low and the pilot sites can serve as models for the rest of the company.
first group that adopts the new system is called the pilot site or the pilot group.
After the system proves successful at the pilot site, it is implemented into the rest of the company using a changeover method (usually direct).
Explain phased changeover, 4 things
company converts one module of the system at a time
different parts of the system are converted at different times
training period is extended
adoption of the new system takes longer
Define data migration
Transfer of data between different formats, storage types and computer systems
Name problems that may arise during data migration. Outline 3.
incapability of moving information due to incompatibility with the new system
Incomplete data transfer during data migration
Data can be misinterpreted due to incompatibilities (differences in how different countries structure data)
Define functional testing
Confirms individual testing commands, perform and function correctly according to specifications
Name and explain the 4 types of data testing
Normal - data that should be accepted
Data at the limits - data at the furthest range that is accepted
Extreme data -Data outside the normal limits
Abnormal data - illegal data
Define Alpha testing
Testing that is done before a software product is made available to the general public - carried out by the company that develops the software
Define beta testing
Done before the software product is made available to the general public (sometimes available to general public) , but includes users outside the company in the testing
Their feedback is valuable to fix errors that were missed
Define dry-run testing
Testing conducted using pen and paper by the programmer
Programmer mentally runs the algorithm
Define unit testing
Individual parts of the system are tested seperately
Define integration testing
The entire system is tested at the same time to verify that all components can work together
Define user acceptance testing
Tests if the system satisfies the customer needs
Carried out in user premises (eg: user office) before accepting transfer of ownership of system
Define debugging
systematic process of finding and correcting the number of bugs in a computer program
Define validation in relation to DATA INPUT
Process of evaluating whether data input follows appropriate specifications and is within reasonable limits
Define verification in relation to DATA INPUT
Process of ensuring that the data input is the same as the original source data
Define validation in relation to software testing
Process of ensuring that a product is being developed for its intended use and function
Define verification in relation to software testing
Process of ensuring that a product meets identified specifications and is being built correctly
What are two types of user documentation
Internal documentation
external documentation
Define internal documentation
code comprehension features provided as part of the source code itself
What does internal documentation include (3)
proper headers for each module
appropriate comments
useful and meaningful variable names
Outline 2 things about external documentation
Typically written as a separate document from the program itself
end-user supporting documents, such as user guides
Name the different methods of providing user documentation (5)
Manuals
Email support
Frequently Asked Questions
Embedded assistance or integrated user assistance
Remote Desktop connections
Features of a manual as a user documentation. Explain 2.
Manuals can be provided online or offline
When provided online as pdf files, it can be downloaded and printed. Printed manual means there is no need for an internet connection.
