Z E M C H 2 0 1 2 I n t e r n a t i o n a l C o n f e r e n c e
426
This process helps the designer to integrate a user needs through planning, extracting
the factors that could fulfil a user needs, then create alternative solutions and finally
assess and evaluate the solution. If these conditions are met then design is ready to be
delivered. If the needs are not met then the designer need to restart the process until the
needs are meet. To meet the user needs, various attributes needs to be considered by
the designer at various stages of the design process. The attributes in user centred
design are explained and listed in ISO 9126.
The attributes of ISO 9126:
The purpose of the standard is to enhance the quality of the software usage. It is
defined as “
a software product quality model, quality characteristics, and related metrics
”
( Zeiss et al., 2007, p.2). As illustrated in fig 6 the standard is made up of six main
attributes. In turn each main attributes is formed from several sub-attribute measurement
metrics. As it has been indicated these guidelines are related to the quality in use. It is
defined as “
the quality perceived by an end user who executes a software product in a
specific context
” (Zeiss et al, 2007, p.2
).
The significance of considering users
aspirations through
out
the design process is imperative in designing the software that
results in a high level of users satisfaction.
The main attributes of the standard are defined by (Lundberg et al, 2005) in table 2.
Table 2: ISO 9126 attributes
The
main
Attributes
The definition of attributes of ISO 9126
Functionality
A set of attributes that relate to the existence of a set of functions
and their specified properties. The functions are those that satisfy
stated or implied needs.
Reliability
A set of attributes that relate to the capability of software to maintain
its level of performance under stated conditions for a stated period.
Usability
A set of attributes that relate to the effort needed for use, and on the
individual assessment of such use, by a stated or implied set of
users.
Efficiency
A set of attributes that relate to the relationship between the level of
performance of the software and the amount of resources used,
under stated conditions.
Maintainability A set of attributes that relate to the effort needed to make specified
modifications.
Portability
A set of attributes that relate to the ability of software to be
transferred from one environment to another.
Figure 6: External and Internal Quality
ISO 9126
