Implementation of Cloud Services in a Business Environment
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Management Task Force, eagerly work on finding a common denominator (Harding,
2011,
p. 89).
7.1.4
Availability
Availability is also an important aspect of business activity, as any downtime means
that processes stand still implying costs without returns. Therefore downtimes need
to be reduced to an absolute minimum. A 0% downtime is nearly impossible. In the
IT business it is very common to describe the uptime of a system by the number of
9
s. In other words, an uptime of 99.9% means that there is an expected downtime
for about 42 minutes per month. A widely recognized standard for the availability
tiers of data centers has been defined by the Uptime Institute, ranging from 99.999%
at Tier 4 down to 97.6% availability at Tier 1. The latter one would imply a downtime
of nearly 9 days per year. Nowadays most cloud service providers have not reached
a Tier 4 yet. As a consequence companies should reflect about this issue as well
and have an exit strategy available (Bauer & Randee, 2012, pp. 22-23) & (Turner,
Seader, Renaud, & Brill, 2008, pp. 4-5).
7.1.5
Reporting
Many cloud service providers charge on a per-usage basis. This being the case, the
reports on the system usage and overall performance must give a meaningful
picture. However a company might have several additional requirements for the
reporting system including information about the average CPU and memory
utilization, or deployed processing units. Especially for employees in the
management it might be of interest to have timely accurate reports in specific
formats in order to support strategies, discover deviations or potential threats
(
Beard, 2008, p. 143f) & (Harding, 2011, p. 94).
