Discuss the benefits of virtualization software. Do you agree/disagree with these benefits?  Also discuss the security concerns highlighted by server sprawl and how you would propose to solve those in your (real or hypothetical) organization. 

Read the following learning materials.

Khelf, & Ghoualmi-Zine, N. (2018). IPsec/Firewall Security Policy Analysis: A Survey. 2018 International Conference on Signal, Image, Vision and Their Applications (SIVA), 1–7. 

Cloud Computing and Virtualization

Supplemental Lecture


Cloud Computing


Cloud Computing



Cloud Computing

Pay-per-use computing model

Customers pay for only the resources they need

May revolutionize computing

Unlike hosted services, does not require long-term contracts

Three service models of cloud computing

Cloud software as a service (SaaS)

Cloud platform as a service (PaaS)

Cloud infrastructure as a service (IaaS)



Cloud Computing Options


Private clouds

Data—managed by the company or offsite by a third party.

Community clouds.

Cloud infrastructure is shared by several organizations

Supports the shared concerns of a specific community.

Public clouds.

Data is stored outside of the corporate data centers

In the cloud provider’s environment

Hybrid clouds

Combination of two or more other clouds.


Public Clouds – Versions

Infrastructure as a Service (IaaS).

Infrastructure through grids or clusters of virtualized servers, networks, storage, and systems software.

Designed to augment or replace the functions of an entire data center.

The customer may have full control of the actual server configuration.

More risk management control over the data and environment.

Platform as a Service (PaaS).

Virtualized servers

Clients can run existing applications or develop new ones

Provider manages the hardware, operating system, and capacity

Limits the enterprise risk management capabilities.


Public Clouds – Versions

Software as a Service (SaaS) or Application Service Provider (ASP).

Software application functionality through a web browser.

The platform and infrastructure are fully managed by the cloud provider.

If the operating system or underlying service isn’t configured correctly, the data at the higher application layer may be at risk.

The most widely known and used form of cloud computing.

Some managers shy away from cloud computing because they are concerned about:

security—specifically about external threats from remote hackers and security breaches as the data travels to and from the cloud.

data privacy.


To manage risk, an SLA needs to spell out these requirements.


Security Challenges

Cloud computing security challenges

Cloud provider must guarantee means to approve authorized users and deny imposters

Transmissions from the cloud must be protected

Customers’ data must be isolated from one another



Virtualization Architectures

Type II Virtualization

Requires a “host” operating system

Using the Type II Hypervisor, you create a virtual hardware environment for each VM

Install a “guest” operating system on each VM, just like installing a new computer

The host operating system shares access to the computer’s processor with the hypervisor

Does not provide the same performance as separate physical computers

Good testing or lab environment


Virtualization Architectures

A hybrid VMM sharing hardware access with a host operating system


Virtualization Architectures

Type I Virtualization

Hypervisor is an abstraction layer that interacts directly with the computer’s physical hardware

No host operating system required

Individual environments, called partitions have their own operating systems installed and accesses hardware through the hypervisor

No host operating system is sharing processor

Parent partition runs the virtualization stack which creates and manages the child partitions


Virtualization Architectures

A Type 1 VMM, with the hypervisor providing all hardware access


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