Business in the Cloud
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each tenant’s database. Every tenant is assigned its own Virtual Machine and a
unique database process that only serves the tenant’s system. This emulates a
process whereas the tenant’s database is being hosted locally (on its own
hardware). Predominantly this model is used in Infrastructure-As-A Service (IAAS)
cloud providers, such as for example Amazon Web Storage (Agrawal, Das, &
Abbadi, 2012, pp. 84-85).
6.4.4.2
Shared Process
Shared process models are usually employed, if the disk bandwidth is the bottleneck
of a database. Hereby tenants share resources within one database process
running at each server. While this sharing can happen at various levels from sharing
only some resources to all of it, it allows for effective resource utilization (Agrawal,
Das, & Abbadi, 2012, p. 85).
6.4.5
Rapid Elasticity
Services can be accessed fast and elastically, in some cases even automatically.
This is necessary in order to guarantee a proper outward and inward scaling
according to the required demand. Consumers often regard these services available
for provisioning to be unlimited and able to be customizable in any quantity at any
time (Mell & Grance, 2011, p. 6) & (Weippl, 2012, p. 16).
6.4.6
Measured Services
The usage of resources is subject to control, supervision and reporting. A pay-per-
use or charge-per-use system provides metering capability appropriate to the type
of service deployed (Mell & Grance, 2011, p. 6) & (Weippl, 2012, p. 16).
