Virtualization Concepts This document discusses various types of virtualization including server, storage, network, and application virtualization. It begins with defining virtualization as creating virtual versions of hardware platforms, operating systems, storage devices, and network resources. Server virtualization partitions physical servers into multiple virtual servers. Storage virtualization pools physical storage to appear as a single device. Network virtualization combines network resources into software-defined logical networks. Application virtualization encapsulates programs from the underlying OS. The document then covers the history of virtualization in mainframes and personal computers and dives deeper into specific virtualization types.

1. Virtualization Concepts
Kingston Smiler. S (kingstonsmiler@gmail.com)

2. About Me
Author
•“OpenFlow CookBook”, which is one
of the recognized study material by
ONF (Open Networking Foundation)
•Learning CoreOS
•1 RFC & 2 IETF Drafts in MPLS and
TRILL WG
•Frequent Presenter in various
networking Forums
•Trainer of SDN, NFV and Network
Virtualization Concepts
Experience
•14+ years of Industry Experience
•6+ years of experience in SDN, NFV
and OpenFlow
•Working as a pre-sales consultant
and product manager
•Having Work Experience in all the
three commercial L2, L3 networking
stack (IPInfusion ZebOS, Aricent ISS,
MetaSwitch L2,L3 and MPLS stack)

3. Virtualization Concepts

4. Session 1: Agenda
What is Virtualization?
Enablers & Need for Virtualization
Does Virtualization a new concept?
Virtualization in various domains
Different types of Virtualization
Server Virtualization
Hypervisors

5. What is Virtualization?
Server
Storage
Network
Wikipedia Definition
Refers to the act of creating a virtual
version of something
Something can either be hardware
platform, operating system, storage
devices, compute / network resources
Typically applicable for compute,
storage & networking
Concept of Virtualization exists from
the very beginning of computer
technology

6. Does Virtualization new concept?
Server
Virtualization
– Mainframes
Storage or
Memory
Virtualization
- Virtual
Memory
Network
Virtualization
- Virtual LAN
(VLAN)
Service
Virtualization
(Java Virtual
Machine)

7. Virtualization Methodologies
Split &
Partitioning
Clustering Mapping

8. Server Virtualization

9. Server Virtualization
Wikipedia Definition
Partitioning of physical server into
number of small virtual servers
Uses Virtualization Software and
hardware virtualization techniques
In most cases the servers are not
utilized fully which results in
inefficient usage

10. Why Server Virtualization
Less Resource Utilization
High Cost
Power Consumption
Server Downtime
High Infrastructure

11. History of Server Virtualization
IBM Mainframes
with Virtualization
Evolution of
Personal
Computers
(1990s)
Back to
virtualization to
reduce Capex and
Opex
(2000s)
1970s 1990s 2000s

12. IBM Mainframes
IBM CP-67 (Mid
1960s)
First Virtualized IBM Mainframe
Server
Split the computer into multiple
virtual machines
Different “tasks” can be run separately
and independently on the same
mainframe
If one virtual machine or “task” has a
problem, other virtual machines are
unaffected

13. Personal Computer Evolution
• Introduction of Intel/AMD servers (x86 architecture)
• Each PC/server runs its own OS (Windows / Unix) and runs application.
• Best approach for personal computers.
• For server and IT infrastructure brings overhead while going for massive
scale.
• Typically in IT and infrastructure deployment one server runs one
application (Email Server, Application Server, DB Server etc)
File
Server
Web
Server
File
Server
Web
Server
File
Server
Domain
Server
App
Server
DNS
Server
Each Server Running
1 Application

14. Server Virtualization

15. Physical Server vs Virtual Server

16. Storage Virtualization

17. What is Storage Virtualization?
Wikipedia Definition
Pooling of physical storage from
multiple storage devices to appear as
single device managed by single entity
Enables better functionality and more
advanced features in computer data
storage systems
Helps the storage administrator to
perform the tasks of backup,
archiving, and recovery more easily
Storage Virtualization can be provided
using software, hardware and
combination of both

18. What is Storage Virtualization?

19. History of Storage Virtualization
1970s 1990s 2000s
OS takes
the individual disks
and create local
volumes within a
logical volume
manager (LVM)
Evolution of RAID
Arrays in 1990s
Evolution of SAN

20. Why Storage Virtualization?
Efficient, Flexible and
Scalable usage of storage
disks
Stable, recoverable and highly
available solution for storage
medium.
Remove hardwire connection
between storage hardware
and the processor

21. Classifications of Storage Virtualization?
Storage
Virtualization
Block Level
Host Based
Storage
Device Based
Network
Based
File Level
Host Based
Storage
Device Based
Network
Based

22. Block Level Vs File Level
Block Vs File Level
Block Level: storage capacity is made
available to the operating system or
the applications in the form of virtual
disks
File Level: Virtualization entity
provides virtual storage to the OS or
applications in the form of files or
directories

23. Host Based Virtualization
Host Based
Virtualization provided by additional
software running (Volume Manager)
directly in the host machine
Volume Manager intercepts the I/O
request and provides metadata lookup
and I/O mapping
OS can also provide this service
Examples are LDM in Windows, LVM
in Linux and ZFS’s Z-Pool in Solaris

24. Storage Device Based Virtualization
Storage Device Based
Virtualization provided in storage
devices is found within intelligent disk
subsystems
The storage systems make their
storage available to servers through
various I/O channels by means of LUN
masking and RAID

25. Network Based Virtualization
Network Based
Two Models: Out-of-band and In-Band
In-band implementations uses
controller between users and
physical storage (SAN) and deliver all
storage requests and data through
that controller
Out-of-band products set up a
metadata controller on the network
that remapped storage requests to
physical locations, but didn’t deal
with the actual data

26. Virtual Machine & Virtual Storage
• VM Migration
• Easily Manageable Disaster Recovery
• High Availability of both Virtual Machine and Storage
• Easy Server Upgrades
• Easy recovery of Virtual Machine Images
• Server Virtualization really calls for a virtualization in the
storage space with centralized management.

27. Application/Service Virtualization

28. What is Service Virtualization?
Application
Operating System
Hardware
Server Virtualization
Application Virtualization
Physical Server
Service Virtualization
Software technology that
encapsulates computer programs from
the underlying operating system on
which it is executed
The application behaves at runtime
like it is directly interfacing with the
original operating system, but can be
isolated or sandboxed to varying
degrees

29. Why Application Virtualization?
Increased Performance
Easy Upgrades and
Installation
On Demand Delivery of
Applications
Applications need not be
installed in all server

30. Server & Application Virtualization
Hyper Visor
Hardware
APP1
Operating System
App
Virtualization
Sandbox
APP2 APP1
Operating System
App
Virtualization
Sandbox
APP2

31. Network Virtualization

32. 32
What is Network Virtualization?

33. What is Network Virtualization?
Network Virtualization
Combining hardware and software network resources and network functionality
into a single, software-based administrative entity, a virtual network
Process of segregating the user traffic from one group of user is getting
forwarded into the same group of user without any logical isolation of the
network infrastructure
Examples are
VLAN in layer2
MPLs L2VPN, L3VPN
Process of splitting the physical network entities like Switches, Routers,
Firewall etc into multiple logical network entities for isolating the user traffic
from different instances
Examples are
VTN using OVS
VTN using ODL etc

34. Introduction
• Process of segregating the user traffic
from one group of user is getting
forwarded into the same group of user
without any logical isolation of the
network infrastructure
• Example VLAN, VRF etc
Definition
1
• Process of splitting the physical network
entities like Switches, Routers, Firewall
etc into multiple logical network entities
for isolating the user traffic from different
instances
• Example VTN
Definition
2

35. Classifications of Network Virtualization
Network
Virtualization
Device Level
Virtual Interface
NIC
TUN/TAP Interface
Bridge, OVS
Virtual Router
Network Level
Network Slicing /
VTN
Packet Level
VLAN
802.1X
802.1AD
MPLS VPN
L2VPN
L3VPN
Interface Level
VRF-lite
OpenFlow SIN

36. In-Device Virtualization
 In-Device Network
Virtualization
 vNIC
 vBridge
 OVS
 TUN/TAP

37. Packet Level Virtualization
 The packet carries
information related to a set
of user for isolation network
traffic.
 Example is VLAN, L2VPN,
L3PVN etc
 In VLAN case, the packet will
carry the VLAN tag which is
used to limit the broadcast
domain of a switch / bridge
 The traffic which is flowing
from a user from one VLAN
will not be forwarded to
other VLAN

38. Interface Level Virtualization
 In this case the traffic
isolation is provided by
assigning set of ports or
interface to a particular
customer.
 The packets from these
ports will be only forwarded
to the interface which is
part of the same VRF.
 Very good example is VRF-
lite

39. Network Level Virtualization
 In Network Level
Virtualization, the entire
physical network is sliced into
multiple logical networks
each assigning to a customer
/ group of customer.
 This kind of network is
termed as virtual tenant
network (VTN)
The network slices are mapped to a customer / tenant and hence termed as
VTN

40. Virtual Machine, Virtual Storage & Virtual Network
Service Virtualization
Server Virtualization
Network Virtualization
Storage
Virtualization

41. Thank you
kingstonsmiler@gmail.com