Flashcards in System Analysis Deck (22)
Carried out when a bug in the program has been identified. e.g. A piece of software may crash when is used with a particular item of hardware
Out to reflect external changes or operate with new hardware / OS e.g. changes to values such as the % rate of VAT or changes to income tax rates will result in changes to software
Improving the performance of the software e.g. configuring network management software to improve the performance such as improving access times to data
A program is released to a restricted audience of testers within the developer’s own company. Carried out in-house by developers/programmers
A program is released to a number of prospective customers or general public in exchange for their constructive comments.Carried out by prospective/typical customers
Carried out by the customer to ensure that the system works correctly
.The summary of an initial investigation to look at the likelihood of creating a new system
Stop using the old system one day and start using the new system the next day
⦿Requires fewer resources (money / people / equipment) and is simple, provided nothing goes wrong
⦿Where failure would not be catastrophic
⦿Element of risk particularly if hardware and software are the latest
⦿If system fails then in can be disastrous
Old ICT system is run alongside the new ICT system for a period of time until all the people involved with the new system are happy it is working correctly
⦿Safest option as if new system fails still has working system
⦿Can compare results and be sure it is working properly
⦿Lots of unnecessary work (as work is being done twice and is therefore expensive in people's time)
⦿Adds to amount of planning needed for implementation
A program module at a time can be converted to the new system in phases until the whole system is transferred
⦿IT staff can deal with problems caused by program modules before moving onto new modules
⦿Staff training can be done in stages
⦿Only suitable for systems consisting of separate program modules
⦿Slower to get system up and running compared to other methods like direct or parallel
This method is ideal for large organisations that have lots of locations or branches where the new system can be used by one branch and then transferred to other branches over time
⦿Difficulties identified in one area can be resolved and manged in next area
⦿Implementation is on much smaller scale
⦿Takes longer to implement the system in all the branches
⦿Department doing the pilot may not have a backup if things go wrong
Methods of investigation
⦿Study existing system documentation.
⦿Carry out a questionnaire of staff.
⦿Observe the current system in practice.
Describe how to use the system to new users. Contains:
⦿Detailed instructions how to navigate, input data ...
⦿Actions to take when errors occur
Used by developer to describe how code & system can be updated and understood.
⦿Data dictionary with descriptions of structure of data used in system
Backup and recovery procedures
How and when data is backed up and how to recover data in event of loss. Contains:
⦿When where data is backed up
⦿Procedures to follow backup
⦿Instructions /steps to recover data after loss.
Health and Safety issues arising from computer use
Describes issues and how to avoid them. Contains:
⦿Risk of RSI- use ergonomically
⦿Risk of eye strain / headaches - correct lighting, looking away regularly
⦿Existing Hardware and Software - Equipment, technical expertise or compatibility issues
⦿Identification of problems with the present system - Does system produce useful outputs?
⦿Analysis of costs and benefits of new system - human resources, consultancy fees, training requirements etc.
Investigation and analysis methods
⦿Inspection of records
Interviews methods Pros and Cons
with managers about the current problems in the system.
⦿Any current problems can be illuminated
⦿Operational staff can supply fine detail on how current system works
⦿Time consuming - lot of people have to be contacted
⦿Needs skilled interviewers to get correct info out of people
Observation method Pros and Cons
Inspects how current system operates
⦿Detail of flow of info and observer can make own judgements.
⦿Can objectively evaluate any time delays/ crashes with current system
⦿Can be time consuming
Inspection of records Pros and Cons
Studying the paper based info / electronic logs produced by the company ATM to identify problems e.g. field lengths causing truncation
⦿Allows one to see what info is currently held in objective manner
⦿The way it is communicated between different departments or customers and the company