Download A virtual machine

In computing, virtualization refers to the act of creating a virtual (rather than actual) version of something, including (but
not limited to) a virtual computer hardware platform, operating system (OS), storage device, or computer network resources.
Virtual Memory
Virtualization began in the 1960s, as a method of logically dividing the system resources particularly memory
provided between different applications. Virtualization of memory required implementations of different applications in a
single operating system.
With developments in technology & concepts, Memory Virtualization allows networked, and therefore distributed, servers
to share a pool of memory to overcome physical memory limitations, a common bottleneck in software performance.
Memory virtualization is also different
from storage based on flash memory such
as solid-state drives (SSDs) and other
similar technologies replace hard-drives,
while memory virtualization replaces or
complements traditional RAM.
As in the figure, it maps memory
addresses, into physical addresses in
process or task appears as a
contiguous segments. The operating
the assignment of real memory to virtual
addresses used by a program, called virtual
computer memory. Main storage as seen by a
contiguous address space or collection of
system manages virtual address spaces and
memory.
Address translation hardware in the CPU,
unit or MMU, automatically translates
Software within the operating system may
address space that can exceed the capacity
memory than is physically present in the
often referred to as a memory management
virtual addresses to physical addresses.
extend these capabilities to provide a virtual
of real memory and thus reference more
computer.
Benefits of Virtual Machines
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Improves memory utilization via the sharing of scarce resources.
Increases efficiency and decreases run time for data intensive and I/O bound applications
Allows applications on multiple servers to share data without replication, decreasing total memory needs
Lowers latency and provides faster access than other storage solutions such as SSD (Solid State Drive), SAN (Storage
Area Network) or NAS (Network Attached Storage)
Virtual Machines
A virtual machine (VM) shares physical hardware resources with other users but isolates the operating system or application
to avoid changing the end-user experience.
Virtual Machine (VM) is a completely separate individual operating system installation on your usual operating system. It
is implemented by software emulation and hardware virtualization.
Virtual machine is a software implementation of a physical machine - computer - that works and executes analogically to
it. Virtual machines are divided in two categories based on their use and correspondence to real machine:
 System Virtual Machines and
 Process Virtual Machines.
First category provides a complete system platform that executes complete operating system, second one will run a single
program.
Frequently multiple virtual machines with their own OS's are used in server consolidation, where different services are run
in separate virtual environments, but on the same physical machine.
A virtual machine (VM) is an operating system OS or application environment that is installed on software which imitates
dedicated hardware. The end user has the
same experience on a virtual machine as
they would have on dedicated hardware.
A virtual machine is a software, that lets
system in your existing computer system.
parent operating system and run just like
operating system.
you create and run a separate operating
You can boot the virtual machine from the
another machine-PC with different
Here the figure shows that a PC using
windows machine can function as if a
VMware software can use in this actual
LINUX system and SOLARIS system
Benefits of Virtual Machines
Main benefits of Virtual Machines can be listed as follows:
 Multiple OS environments can exist simultaneously on the same machine, isolated from each other;
 Virtual machine can offer an instruction set architecture that differs from real computer's;
 Easy maintenance, application provisioning, availability and convenient recovery.
 Server consolidation, increased utilization and faster recovery times after failure are also benefits of virtual machines.
Server Virtualization
Server virtualization is the masking of server resources, including the number and identity of individual physical servers,
processors, and operating systems, from server users. The server administrator uses a software application to divide one
physical server into multiple isolated virtual environments.
Benefits of Virtual Server
Main benefits of Server Virtualization can be listed as follows:
 Server consolidation helps to create multiple environments.
 It creates increased utilization of physical resources and
 It is also faster at recovery times after failure.
Virtualization Certifications
Virtualization is an excellent development in the technology, which is extensively used in the field today because of its
benefits. These days, all new technological developments are supported by providing training and certification by the
companies, who are involved in the development of the technology. Main Virtualization Certificates can be listed as
follows:
VMware Virtualization certifications:
 VMware Certified Associate
 VMware Certified Professional
 VMware Certified Implementation Expert
 VMware Certified Design Expert
Citrix Virtualization certifications:
 Certified Professional - Virtualization (CCP-V)
Red Hat Virtualization Certifications:
 RHCVA: Red Hat Certified Virtualization Administrator
Cisco Virtual Certifications:
 Cisco Data Center Unified Computing Support Specialist
Microsoft Virtualization Certification:
 Microsoft Certified Solutions Expert: Private Cloud (MCSE: Private Cloud)
The above certifications are among top 5. There are 2 more players in the field. These are IBM and Oracle. Future will
depend on the developments done in future by these companies.