3. Control. By keeping modules small, they are less likely to contain material errors of fraudulent logic. Since each module is independent of the other , errors are contained within the module.
Test the application software
All program module must be thoroughly tested before they are implemented . there are some proven concepts about testing that should be followed by the system developers, and considered by auditors in conducting audits.
Testing methodology. The process itself has structured step to follow. Figure 5.8 show a program-testing procedure involving the creation of hypothetical master files and transaction files that are process by the modules being tested. The result of the test are then compared againt predetermined results to identify programming and logic errors. For example in testing the logic of the accounts receivable update module illustrated in figure 5.8 the programmer might create an account receivable master file record for john smith with a current balance of $1,000 and a sales order transaction record for $100.before performing the update test the programmer concludes that a new balance of $1,100 should be created to verify the module’s internal logic, the programmer compares the actual results obtained from the run with the pre-determined results. This example is a simple one of a program test. actual testing would be extensive and would involve many transaction that test all aspects of the module’s logic
Testing offline before deploying online the first point that is critical in testing is to never underestimate the principle of testing before deploying a system online implementing a system without testing offline is an invitation to disaster one online e-commerce firm went out of business because it implemented a system online without testing it offline first and accidentally left a vulnerable web server open to attacks from cracker. A cracker stole thousands of credit card number and eventually the online business failed.
Test data creating meaningful test data is an extremely time-consuming aspect of program testing
This activity can however provide future benefits as we shall see in chapterv7 application auditing sometimes involves program testing to facilitate future testing test data prepared during the implementation phase should be retained for reuse this test data will give the auditor a frame of reference for designing and evaluating future audit tests for example if a program has undergone on maintenance changes since its original implementation the test result from the audit can thus focus attention upon those areas maintaining test data and its results is also a significant control feature as future as future systems development can use the test data and results to test future changes to application software.
System implementation – phase vii
In the system implementation phase of the systems development process, database structures
Are created and populated with data equipment is purchased and installed the implementation process engager the efforts of designers programmers database administrators, users, and accountants the activities in this phase entail extensive costs and will often consume more. Personnel-hour than all other preimplementation phases of the SDLC combined
Testing the entire system
When all modules have been coded and tested they must be brought together and tested as a
Whole user personnel should direct system-wide testing as a prelude to the formal system implementation the procedure involves processing hypothetical data through
The system the output of the system are then reconciled with predetermined results.
And the test is documented to provide evidence of the system ‘s performance finally
When those conducting the tests are satisfied with the results, they should then complete
A formal acceptance document this is an explicit acknowledgment by the user that the system
In question meet stated requirement the user acceptance document becomes important in
Reconciling differences and assigning responsibility during the post-implementation review of the system
Documenting the system
The system’s documentation provides the auditor with essential information about how the system
Work’s the documentation requirement of three group—systems designers and programmers computer operators and end users—are of particular importance
Designer and programmer documentation.
System designers and programmers need documentation to debug errors and perform maintenance on the system this group is involved with the system on a highly technical level, which requires both
General and detailed in formation some of this is provided through data flow diagrams,entity relation(er)diagrams and structure diagrams in addition system flowcharts,pro-gram flowcharts and program code listings are important forms of documentation the system flowchart shows the relationship of input files programs and output files however it does