To look at an existing system and then designing a new system which can carry out same tasks better

1.Analysis, 2.Design, 3.Development and Testing, 4.Implementation, 5.Documentation, 6.Evaluation

Current system is looked in detail to find out what changes need to be made to make the new system better than old one

• Observation

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See image

See image

Involves watching personnel using the existing system to find out exactly how it works

Involves a one-to-one Q&A session between he analyst and the employee/customer

Involves distributing questionnaires to the workforce, clients or system users to find out their views of the existing system and to find out how some of the key tasks are carried out

Allows analyst to see how the paper file are kept, look at operating instructions and training manuals, check the accounts, etc. It allows the analyst to get some idea of the scale of the problem, memoir size requirements, type of input/output devices needed, etc.

analyst obtained reliable data and relatively inexpensive

time-consuming and relatively expensive (analyst's time)

relatively inexpensive and quick analysis of data

allows information to be obtained which wasn't possible by other methods

Collecting data about the current system/proposed system and finding out problems with the current system

Plan the proposed system

Creating the data entry screens, user interface layouts, printed outputs, screen based outputs, structures to store data

A process where data is checked to see if it satisfies certain criteria when input into a computer i.e. to see if the data falls within accepted boundaries

length check, type check, format check, presence check, check digit

Checks that correct number of characters are entered

Checks that entered data doesnot contain invalid characters

Makes sure that data is in a specific format

Checks that data has been entered and not missed out

Verification is checking that the data entered is correct and matches the source of data

Double entry and Visual

Means to build the system

Creating file structures to store data, Creating validation rules to make sure data entered is sensible, Create a user interface to allow data to be input into the system, Create output formats

Once system has been developed,it has to be tested to see if it functions properly

Normal, Extreme, Abnormal, Live

Data with known outcomes

Data that is acceptable/reasonable and has an expected (known) outcome

It means to install the system ready for use or put the system to work

Data outside the limits of acceptability, or the wrong type of data, and should be rejected or cause an error message

Data at the limits of acceptability

Direct changeover, Parallel running, Pilot running, Phased implementation

the old system is stopped overnight and the new system is introduced immediately

the old and new systems are run side by side for a time before the new system takes over altogether

The new system is introduced into one branch or office of the company and its performance is assessed before being introduced elsewhere in the company

Only part of the new system is introduced and, only when it proves to work satisfactorily, is the next part introduced, and so on, until the old system is fully replaced

Very cheap, Some input needed by the user but high probability of failure

Relatively inexpensive and almost no input needed by the user

fastest way of changing from one system to another and new system can be immediately used after installation

Relatively inexpensive, some input needed by the user and systems team

Almost no input needed by systems team and low probability of failure

failure isn't disastrous. Old system is still available and it is possible to gradually train staff on the system

if the new system fails, only one part is affected and the costs are less than parallel

failure isn't disastrous, can go back to point of failure if latest part fails and can ensure the system works properly before expanding

Technical and User Documentation

helps programmers/analysts to make improvements to the system or to repair/maintain the system

The purpose of the system, Hardware, Software and Memory requirements

User documentation is needed because it helps users to learn how to use the software or system

open/load system, log in log out of the system, search the system data and inputting data

compare the solution with the original task

place the new system into the company

create user guides for everyday users and those who will develop further

describe how well the new system is working

very time-consuming and more expensive than 'direct changeover'

the old system is completely removed so there is nothing to go back to if new system fails and it is time consuming and difficult to plan

more expensive than 'direct' method and time consuming because each part needs to be fully evaluated before making further changes

is where data is entered twice by two different people.

is where person entering data into the computer can compare what they have entered with the original document

people may work in a different way as most are uncomfortable being watched and if workers perform tasks that are against standard procedures, they may not do this while being watched