Cloud Computing Concepts:
as a service (IaaS) comprises the cloud service model which provide access
to computing resources in virtualized environment “the cloud”
across a network connection usually
IaaS is one of the three fundamental service
models of cloud computing along with Platform as a service (PaaS) and Software
as a service (SaaS)
IaaS enables access to fundamental resources
such as physical machines, virtual machines, virtual storage etc.
Apart from these resources, the IaaS also offer
Virtual machine disk storage, Virtual local area network (VLANs), Load
balancers, IP addresses and software bundles etc.
All the resources are made available to end user
via server virtualization. Moreover,
these resources are accessed by the customers as if they own them.
Physically, the pool of hardware resource is
pulled from a multitude of servers and networks usually distributed across
numerous data centers, all of which the cloud provider is responsible for maintaining.
The client, on the other hand, is given access
to the virtualized components in order to build their own IT platforms.
IaaS can be utilised by enterprise customers to
create cost effective and easily scalable IT solutions where the complexities
and expenses of managing the underlying hardware are outsourced to the cloud
If the scale of a business customer’s operations
fluctuate, or they are looking to expand, they can tap into the cloud resource
as and when they need it rather than purchase, install and integrate hardware
IaaS can be utilized in Enterprise Infrastructure, Cloud hosting, Virtual Data Centers (VDC)
Features and Benefits of IaaS:
independence: the service can usually be accessed from any location as long
as there is an internet connection and the security protocol of the cloud
Physical security of
data center locations: services available through a public cloud, or
private clouds hosted externally with the cloud provider, benefit from the
physical security afforded to the servers which are hosted within a data center
resource is available as and when the client needs it and, therefore, there are
no delays in expanding capacity or the wastage of unused capacity
costing: the service can be accessed on demand and the client only pays for
the resource that they actually use
No single point of
failure: if one server or network switch, for example, were to fail, the
broader service would be unaffected due to the remaining multitude of hardware
resources and redundancy configurations.
For many services if one entire data center were to go offline, never mind
one server, the IaaS service could still run successfully.
No investment in
hardware: the underlying physical hardware that supports an IaaS service is
set up and maintained by the cloud provider, saving the time and cost of doing
so on the client side.
Here are the characteristics of IaaS service model:
On-demand availability of resources.
Virtual machines with pre-installed software.
Virtual machines with pre-installed Operating
Systems such as Windows, Linux, and Solaris.
The computing resources can be easily scaled up
Allows to store copies of particular data in
Data Erase Practices:
The consumer uses virtual machines that in turn uses the common disk resources
provided by the cloud provider. When the consumer releases the resource, the
cloud provider must ensure that next consumer to rent the resource does not
observe data residue from previous consumer.
legacy security vulnerabilities: Because IaaS offers the consumer to run
legacy software in provider's infrastructure, therefore it exposes consumers to
all of the security vulnerabilities of such legacy software.
VM-level isolation: IaaS offers an isolated environment to individual
consumers through hypervisor. Hypervisor is a software layer that includes
hardware support for virtualization to split a physical computer into multiple
sprawl: The VM can become out of date with respect to security updates
because IaaS allows the consumer to operate the virtual machines in running,
suspended and off state. However, the provider can automatically update such
VMs, but this mechanism is hard and complex.