BY AJIT SINGH NEGI Dehradun

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2. WHAT IS CLOUD COMPUTING ???
• Cloud computing is a model for enabling on-demand access to shared pool of
compute resources e.g. server, application ,data storage and infrastruture.
• In other words, cloud computing is a model for delivering IT services. Instead of
a direct connection to the server as in case of traditional client server computing,
the resources are retrieved from the Internet though web-based tools and
applications.
• Application and databases are stored in servers. The cloud computing structure
allows access to cloud resources as long as an devices has access to the web.
This allows employees to work remotely and to pay only for what he access.
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3. Virtualization: This computing paradigm virtualizes systems by pooling and
sharing resources. Resources can be provisioned as needed from a centralized pool
of resources, costs are assessed on a metered basis, multi-tenancy is enabled, and
resources are scalable with agility. So one of the most important ideas behind this
paradigm is Scalability and the key technology that makes that possible is
Virtualization.
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4. What is Virtualization ???
• Virtualization, in computing, is the creation of a virtual (rather than
actual) version of something, such as a hardware platform, operating
system, a storage device or servers.
• Ability to emulate hardware via software.
• The ability to run multiple operating systems (single user or multiuser) on
a single physical system and share the underlying hardware resources
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5. Before Virtualization
What were the limitation?
 Single OS image per machine
 Software and hardware tightly
coupled
 Running multiple applications
on same machine often creates
conflicts.
 Underutilized resources
 Inflexible & costly
infrastructure
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6. After Virtualization
What are the benefits now ?
 Hardware-independence of
operating system and
applications
 Virtual machines can be
provisioned to any system
 Management of OS and
application as a single unit by
encapsulating them into virtual
Machines
 Better Utilization of resources
taken place
 Maintenance would be very
easy
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7. VIRTUAL MACHINE
• A virtual machine (VM) is a software based, virtual computer.
• Software implementation of a machine (i.e. a computer) that executes
programs like a physical machine.
• Classified into two majors:
• A system virtual machine provides a complete system platform which
supports the execution of a complete operating system.
• A process virtual machine (language virtual machine like java JVM) is
designed to run a single program, which means that it supports a single
process.
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8. • Definitions
– Hypervisor (VMM – Virtual Machine Monitor) is a software layer that
allows several virtual machines to run on a physical machine
– The physical OS and hardware are called the Host
– The virtual machine OS and applications are called the Guest
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VMware ESX, Microsoft Hyper-V
Hardware
Hypervisor
VM1 VM2
Type 1 (bare-metal)
Host
Guest
Hardware
OS
Process Hypervisor
VM1 VM2
Type 2 (hosted)
VMware Workstation, Microsoft Virtual PC
Host
Guest
TYPES OF HYPERVISOR

9. Types of Virtualization
• Full Virtualization.
• Para Virtualization.
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10. FULL VIRTUALIZATION
• Almost complete simulation of the actual hardware to allow guest
operating system, to run unmodified.
• Full virtualization is important for running non-open-source operating
system such as Windows, because it is too difficult to modify the Windows
kernel without source code .
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11. PARA VIRTUALIZATION
• A hardware environment is not simulated,however, the guest programs are
executed in their own isolated domains, as if they are running on a separate
system. Guest programs need to be specifically modified to run in this
environment.
• Para virtualization requires the guest OS kernel to be modified to become
aware of the hypervisor.
• OS-level information about the VM can be passed explicitly from the OS
to the VMM, and this is done in practice to some extent.
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12. Key Features of Virtualization
Partitioning
•Different OS can run on one physical machines
•System resources can be divided between
virtual machines.
Isolation
Fault and security isolation on a hardware
level
Extended resource control for constant
performance.
Encapsulation
Complete status of a virtual machine can be
stored in a file.
Move and copy of a virtual machine is as easy
as it is with files.
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13. Server Virtualization in
Cloud Computing Environment
110 Servers without VMware software
EQUALS TO
12 Servers, 1 rack with VMware software
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14. Storage Virtualization in
Cloud Computing Environment
 It involves the virtualization of physical storage devices/servers.
 It allows many different users or applications to access storage, regardless
of where that database server is located or what kind of storage device it is.
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Amazone S3 Storage

15. Virtual Machine Migration OR Load Balancing in
Cloud Computing Environment
• The Virtualization allows the live migration of virtual machines from one
physical server to another and needs therefore no downtime for maintenance
activities.
• Move running applications to other servers without disruption, Zero
downtime for hardware maintenance.
• Automates moving virtual machines to other hosts and automates re-
balancing after maintenance complete.
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16. Unplanned Downtime OR Server Failure handling in
Cloud Computing Environment
• Automatic restart of virtual
machines in case of server
failure.
• No need for dedicated stand-
by-hardware.
• None of the cost and
complexity of clustering.
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17. SECURITY CHALLENGES
• Scaling: Virtualization enables rapid creation and addition of new virtual
machines. Without total automation, this dynamic growth capacity can
destabilize security management activities such as system configuration
and updates, resulting in vulnerability to security incidents .
• Diversity: Increased heterogeneity of operating systems and environments
will increased security management difficulties, and present a more varied
attack surface.
• Identity: Static means of identifying machines, such as MAC addresses or
owner name, may not function with virtualization. Machine ownership and
responsibility is harder to track in a dynamic virtualized environment .
• Data lifetime: Guest OS‘s may have security requirements about data
lifetime that are invalided by a VMM‘s‘ logging with VM mobility, it is
possible that sensitive data may be left in widely distributed persistent
storage.
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18. Conclusion
“Virtualization is one of the main cost-saving, hardware-reducing, and
energy-saving techniques used by cloud providers”
 With OS virtualization each VM can use a different operating system (OS),
and each OS is isolated from the others and it can run different services .
 Less number of servers required for the same number of applications to
run. IBM Smart cloud and Amazone ES2 uses server virtualization heavily.
 Less maintenance overhead for the IT staff.
 More resource utilization and less power consumption thus increase
profits.
 Easier (and faster) to increase or decrease load on servers(Load balancing).
 DRP (Disaster Recovery Planning) becomes easier. Without any
interruption to the service, one can backup and even migrate entire virtual
environments.
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