1. Characteristics of virtualized environment Virtualization reference model
Virtualization Layer
Virtual Hardware
Virtual Networking
Virtual Storage
Software Emulation
Host
Physical Hardware
Physical Storage
Physical Networking
Guest
Applications
Virtual Image

2. Increased security
Managed Execution
A)Sharing
B) Aggregation
C)Emulation
D)Isolation
Portability

3. Taxonomoy of Virtualized Environment
Virtualization
Execution Environment
Storage
Network ….
Emulation
High-Level VM
Multiprogramming
Hardware-assisted
Process Level
System Level
Paravirtualization
Full Virtualization
How it is done?
Technique
Virtualization Model
Application
Programming Language
Operating System
Hardware
Partial Virtualization

4. Execution virtualization 1)Machine reference model
Libraries
API
ABI
Hardware
Operative System
ISA
Applications
API calls
System calls
User

5. 2 Hardware Level virtualization
Host
VMM
Virtual Machine
binary translation
instruction mapping
interpretation ……
Guest
In memory
representation
Storage
Virtual Image
Host emulation

7. 3)Hardware Virtualization techniques
Hardware assisted virtualization
Full virtualization
Para virtualization
Partial virtualization

8. Hypervisors

9. 4) OS level virtualization offers the opportunity to create different and separated execution environments for applications that are managed concurrently. It is different from hardware virtualization —there is no virtual machine manager or hypervisor, and the virtualization is done within a single operating system, where the OS kernel allows for multiple isolated user space instances.

10. 5)Programming level virtualization is mostly used for achieving ease of deployment of applications, managed execution, and portability across different platforms and operating systems. It consists of a virtual machine executing the byte code of a program, which is the result of the compilation process.

11. 6)Application level virtualization Interpretation Binary Translation

12. Virtualization and cloud
Server A
(running) VM
Server B
Virtual Machine Manager
(inactive)
Before Migration
After Migration

13. Advantage and disadvantage of virtualization
Advantages:
Eliminates the need for numerous dedicated servers;
Offers the ability for different domain names, file directories, administration, IP addresses, logs and analytics;
Cost effective because many times server software installation provisioning is available;
If one virtual server has a software failure, the other servers will not be affected;
Reduces energy costs because only one device is running instead of several;
Offers a flexibe IT infrastructure;
Can quickly make changes with little downtime.

14. Disadvantages
Resource hogging could occur if there are too many virtual servers within a physical machine;
As software updates and patches must be compatible with everything running on the virtual machine, admins may have reduced control over the physical environment;
Administration, including backup and recovery, requires specialized knowledge;
If user experience is impacted, it can be difficult to identify the root cause;
Services offered by a dedicated server are more accessible.