Portability – measure of (effort) how easily a software can be moved from one environment to another. The
effort may also involve data migration, documentation and other similar activities
– Hardware independence: The ability of a system or software to output the same set of results
independent of the hardware that it is installed on.
– Interoperability: It is the ability of two or more systems or subsystems or components to exchange
information and to use the information further that has been exchanged
• Reliability - According to ANSI, Software Reliability is defined as the probability of failure-free software
operation for a specified period of time in a specified environment. However it is not a direct function of time. It
is one of the very important attributes of quality and will become harder to achieve as the complexity of the
software increases.
– Error Tolerance: It is the ability of a system or component to continue normal operation despite the
presence of erroneous inputs either from the user or from a different interface system
– Availability: It is the proportion of time that the system is up and running i.e. available for its intended
users. It can be measure as: Uptime/(Uptime + Downtime)
• Usability – Measure of how easy or difficult it is to use a software. It refers to the efficiency, comfort, safety
and satisfaction with which intended users of a software and under a variety of conditions can perform their
tasks
– Understandability: The measure of effort required understand the overall functionality of a system
– Learnability: How easy is it for users to accomplish basic tasks the first time they encounter the system
features
– Operability: It is the ability to keep a system in a functioning and operating condition.
– Communicativeness: The ability to express or communicate the messages or status of the system to
the external world in a clear and unambiguous way
