virtualization

virtualization

1. Virtualisation often includes computer-generated versions of hardware, operating systems, storage devices and more. This allows organisations to partition a single physical computer or server into several virtual machines.

2. Benifits

   • Reduced capital and operating costs.
   • Minimized or eliminated downtime.
   • Increased IT productivity, efficiency, agility and responsiveness

3. Challenges

   • Lack of application awareness— OS virtualization doesn’t virtualize the application
   • Additional, unanticipated costs—the virtual solution costs more than the physical problem
   • Unused virtualization features—the network limits implementation
   • Overrun storage network—growth exceeds planning

4. Drawbacks

   • It can have a high cost of implementation
   • Sicurity
   • Scalability
   • Limitated

5. Hypervisors

   • Type1
     • A Type 1 hypervisor runs directly on the host machine's physical hardware, and it's referred to as a bare-metal hypervisor.
   • Type2
     • A Type 2 hypervisor is typically installed on top of an existing OS. It is sometimes called a hosted hypervisor because it relies on the host machine's preexisting OS to manage calls to CPU, memory, storage and network resources.

6. Example

   • Application virtualization
   • Desktop virtualization
   • Server virtualization
   • Storage virtualization
   • Network virtualization

7. Types

   • Application Virtualization
     • Application virtualization is a way of delivering software inside a virtual structure, without needing the software to be installed on individual devices. The user can access the virtualized application on-demand, leveraging their individual device’s hardware.
     • Benifits
       • Reduced Ongoing IT Costs
       • Employees (or Students) Can Work From Anywhere
       • Users Can Work on Their Own Device
       • Apps Can Be Easily Kept Updated
       • Multiple runtime environments
       • Simplified roaming
       • Reduced regression testing
     • Demerits
       • High Upfront Costs
       • Not All Software Can Be Virtualized
       • standard updates do not usually work, as the application must be virtualized with the installed update.
     • Types
       • Remote Application Virtualization
         • Remote applications run over a server, end users can view and interact with their applications on a network through remote control protocol.
         • The remote programs can be completely integrated with the user’s desktop so that they appear and act like local applications, with the aid of technology known as seamless windows.
         • A constant network connection must be required and maintained to run remote applications properly.
       • Streaming Application Virtualization
         • In streaming application,the virtualized application is executed on the end-users local computer.
         • When an application is requested, its components are directly fetched to the local computer on demand.
         • Certain parts of the application are required in order to launch, rest can be downloaded in the background as needed.
   • Network Virtualization.
   • Desktop Virtualization.
     • Desktop virtualization allows the users’ OS to be remotely stored on a server in the data centre. It allows the user to access their desktop virtually, from any location by a different machine. Users who want specific operating systems other than Windows Server will need to have a virtual desktop. Main benefits of desktop virtualization are user mobility, portability, easy management of software installation, updates, and patches.
     • Benefits
       • Simpler administration
       • Cost savings
       • Improved productivity
       • Support for a broad variety of device types
       • Stronger security
       • Agility and scalability
       • Better end-user experiences
     • Major Models
       • Hosted Desktop
         • Virtual Desktop Infrastructure (VDI)
           • Great for organizations that want to build their own infrastructures
           • Great for organizations that want to have absolute control over their IT infrastructure
           • Suitable for local regions or co-location data centers that are close to users’ data
         • Remote Desktop Services (RDS)
           • Great for organizations that want to develop their own infrastructures
           • Great for organizations that want to have absolute control over their IT infrastructure
           • Suitable for local regions or co-location data centers that are close to users’ data
         • Desktop-as-a-Service (DaaS)
           • Great for organizations that want to consume desktop virtualization “as a service.”
           • Great for organizations that want more use cases and update cycles
           • Suitable for dispersed data centers that reside in the public cloud
       • Client Virtualization
         • Presentation virtualization
           • Application virtualization allows apps to run on other platforms. For example, you can run Windows apps on Linux. You can use Application virtualization to simplify OS migration by creating portable software. You can then transfer applications between computers without having to install them.
         • Application virtualization
           • Presentation virtualization provides a web-based portal through which users leverage to interact with published desktops and apps. Organizations can use this approach to deliver apps or desktops from a shared server.
     • Demerits
       • Points of failure are reduced to a few centralized servers
       • Network dependency
       • https://www.goconqr.com/en-US/mind_maps/32946866/edit#
   • Storage Virtualization.
   • Server Virtualization.
   • Data Virtualization.