Scenario
CAET have implemented a bespoke Human Resources (HR) system. The system has gone live but it has not proved very
popular or successful, with users claiming that it only partly fulfils their requirements. A consultant has been hired to
examine their claims and to suggest how their concerns might be tackled.
The consultant’s report has highlighted the role played by the Requirements Specification. He suggests that the
Requirements Specification’s reliance on ambiguous textual specifications has led to problems of ill-defined and poorly
communicated requirements. He claims that the ‘analyst’s failure to use diagrammatic models has meant that many
requirements were not fully understood before they were programmed. Specifications without diagrams are very difficult to
quality assure.’ His report quotes several examples of textual specifications. Two specifications are reproduced below;
Specification 1(field names are shown in italics)
The system should hold information about Jobs (job number, job description, grade) and about the Departments
(department name, department head) that these Jobs are in. A Department may have many Jobs allocated to it, but one
Job is only in one Department. When these Jobs become vacant they should be advertised in both Internal and External
media. The information that must be stored is
date advertised, size of advertisement, noticeboard location
(for internaladvertisement only),
newsletter reference
(for internal advertisement only),
newspaper edition
(for external advertisementonly) and cost of advertisement
(for external advertisement only). Information about Applicants (applicant name, applicantaddress) is required, specifying which Job they are applying for and where they saw the Job advertised.
Specification 2
When an application form is received from an Applicant, a Clerk enters the information on the form into the system. As it
is entered, it is validated against Job details to ensure that the Applicant is applying for a valid Job. Once details have been
entered they are stored on an Applicant database. Overnight a batch process is run to send an acknowledgement letter to
each Applicant. The date that the letter is sent is noted on the Applicant details held in the system.
Redefinition Project
The consultant has suggested a Redefinition Project to address the problems encountered by the users. He says that,
‘I am suggesting a mini-project with agreed Terms of Reference and a project plan. These problems need to be addressed
in a planned manner’.
The consultant is keen to stress that he does not wish to over-engineer the software solution. ‘We have to ensure that the
trade-off between time, cost and quality is appropriate for the delivered software’, he says, ‘the delivered software must be
appropriately located on the time/cost/quality triangle.’
1The consultant has recognised that ambiguous textual specification has contributed to the software’s problems. He
claims that the ‘analyst’s failure to use diagrammatic models has meant that many requirements were not fully
understood before they were programmed.’ The implication is that the use of such diagrammatic models in analysis
would have solved many of the ambiguities of the specification.
(a)Specification 1 in the scenario describes static structures, which could be modelled with a class model, entity-
relationship model or logical data structure model.
(i)Briefly explain the notation of EITHER a class model OR an entity-relationship model OR a logical data
structure model;(4 marks)
(ii)Using this notation, model the information given in Specification 1. Note any assumptions you have
made or issues you would need to clarify with the user. Your answer should indicate the fields in each
entity/class.(6 marks)
