Technical Computer Science 6
Virtualization Systems and Technology
Lecture 1
Introduction to Virtualization Technology
Lecturer: Ab. Rahman Vakili
E-Mail: vakili.hu.it@gmail.com
Definition
“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
network resources”
Concept is not new.
Multi Programming – Each Process thinks it has complete
control on all of the resources.
Virtual Memory
CPU Sharing
Similarities and Differences with
Multiprogramming
• CPU is shared • CPU is shared among
among processes OSs.
• Memory is shared • Multiple Page tables.
using Page Tables. • OS may or may not
• Process knows it is know that it is being
being managed managed.
using system calls.
Virtualization Models
Server Virtualization (SerV):
Is focused on partitioning a physical instance of an operating system into a virtual
instance or virtual machine. True server virtualization products will let you virtualize
any x86 or x64 operating system, such as Windows, Linux, and some forms of UNIX.
There are two aspects of server virtualization:
■ Software Virtualization (SoftV) runs the virtualized operating system on
top of a software virtualization platform running on an existing operating
system.
■ Hardware Virtualization (HardV) runs the virtualized operating system
on top of a software platform running directly on top of the hardware
without an existing operating system.
The engine used to run hardware
virtualization is usually referred to as a hypervisor. The purpose of this
engine is to expose hardware resources to the virtualized operating systems.
Virtualization Models
Storage Virtualization (StoreV):
Is used to merge physical storage from multiple devices so that they
appear as one single storage pool. The storage in this pool can take
several forms: direct attached storage (DAS), network attached storage
(NAS), or storage area networks (SANs); and it can be linked to through
several protocols: Fibre Channel, Internet SCSI (iSCSI), Fibre
Channel on Ethernet, or even the Network File System (NFS).
Virtualization Models
Network Virtualization (NetV):
lets you control available bandwidth by splitting it into independent
channels that can be assigned to specific resources.
For example, the simplest form of network virtualization is the virtual
local area network (VLAN), which creates a logical segregation of a
physical network.
Virtualization Models
Management Virtualization (ManageV):
Is focused on the technologies that manage the entire datacenter, both
physical and virtual, to present one single unified infrastructure for the
provision of services.
In this model two main parts are considered:
Resource Pools (RP), which includes the collection of hardware
resources (host servers, racks, enclosures, storage, and network
hardware) that makes up the datacenter infrastructure
Virtual Services Offerings (VSO), or workloads that are made up of the
virtual machines (servers and/or desktops) that are client-facing and offer
services to end users
Virtualization Models
Desktop Virtualization (DeskV):
Allows you to rely on virtual machines to provision desktop systems. Desktop
virtualization has several advantages, the least of which is the ability to
centralize desktop deployments and reduce distributed management costs
because users access centralized desktops through a variety of thin or
unmanaged devices.
Virtualization Models
Presentation Virtualization (PresentV):
Until recently called Terminal Services, provides only the presentation layer from
a central location to users. While the need for PresentV is diminishing because
of the introduction of technologies such as Application Virtualization, the
protocols used for PresentV are at the forefront of both DeskV and SerV
technologies since they are the protocol used to access, use, and manage
virtual workloads.
Virtualization Models
Application Virtualization (AppV):
Uses the same principles as software based SerV, but instead of
providing an engine to run an entire operating system, AppV decouples
productivity applications from the operating system.
