Australian Government Architecture Reference Models Version 3.0

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Measurement Area Rationale Defined by
[5302]
Availability (technology)
[5303]
Reliability (technology)
Measuring the availability of
technology as an input is
measuring how much technical
labour is available for the
execution of business
processes and tasks
(undertaking of work).
Availability is a bivariate
attribute that compares the total
volume of technology labour
available (capacity) with the
volume of technology labour
already consumed or committed
(utilisation).
Knowing the availability of
technology resources facilitates
efficient capacity management
of agency projects, operational
processes and other activities
the agency engages in.
The reliability attribute of
technology can be both
multivariate and univariate.
When employed as an indicator
of empirical performance
(stability), univariate
measurement will suffice. When
used to inform risk
management and activity
planning exercises, a
multivariate measurement that
incorporates age and physical
impairment (wear) is necessary.
Australian Government Architecture Reference Models Version 3.0
A. Capacity
Quantitative measures of the maximum workload that a
piece of technology is able to service. Measurement
indicators within this grouping may include:
� maximum bandwidth of a networking switch
� maximum number of concurrent connections a
database can maintain
� how much data a storage device can hold
� how much processing power a piece of equipment
has (desktop, server, mainframe etc.).
B. Utilisation
Quantitative measures of the technology labour
consumed by or reserved for the execution of business
processes. Utilisation of technology resources is the
amount of processing power (labour) consumed in
servicing a particular process or activity. Measurement
indicators within this grouping could include:
� percentage of processor time consumed
� volume of disk space consumed
� volume of network bandwidth consumed.
A. Age
Qualitative measures of the age of technology, as age
can be a determinant of the reliability of the technology.
For example, the incidence of failure of magnetic tape
as a storage medium increases over time because the
magnetic particles embedded in the tape lose their
ability to hold charge over time.
B. Stability
Quantitative measures of the rates of error and rates of
failure of technology. Measurements of technology
reliability include, but are not limited to:
� mean time between hardware failures
� average rate of software errors
� volume of networking and telecommunications
outages
� frequency of data centre outages.