Explain the characteristics of virtualized environments

3.A) Explain the characteristics of virtualized environments. – 7 Marks

Answer:-

Characteristics of Virtualized Environments:

1. Components of Virtualized Environment:
   • Guest: The system component that interacts with the virtualization layer instead of directly with the host system.
   • Host: The physical environment where the guest operates, including the underlying hardware and sometimes the operating system.
   • Virtualization Layer: Manages the creation of virtual environments and translates the guest’s operations to the host system.
2. Increased Security:
   • The virtualization layer controls and filters the execution of guest operations, providing security and preventing harmful operations.
   • Sensitive host data can be protected from the guest without complex security policies.
   • Virtualization is especially useful for running untrusted code, such as Java applets or applications in a sandboxed environment.
3. Managed Execution:
   • Virtualization enables various features like sharing, aggregation, emulation, and isolation:
     • Sharing: Allows the use of powerful guest systems within the same host, optimizing resource usage.
     • Aggregation: Combines resources from multiple physical hosts and presents them as a single virtual resource to guests.
     • Emulation: Simulates hardware or system environments, enabling the execution of programs that require specific hardware or system characteristics.
     • Isolation: Ensures that guests operate in separate environments, preventing interference between guests and from the host system.
4. Performance Tuning:
   • Virtualization allows fine-tuning of resource allocation (e.g., limiting memory or processor frequency), improving performance and enabling quality-of-service (QoS) management.
   • Virtual machine managers can capture and store the state of a guest system and resume its execution on different machines, facilitating seamless migration.
5. Portability:
   • Virtualized environments offer high portability. Virtual images can be moved and executed on different virtual machines, similar to displaying an image across devices.
   • Virtual machines like JVM or .NET runtime allow applications to run across different platforms without recompilation, enhancing flexibility in application development and deployment.
   • Virtualized environments enable users to carry their entire system and work on it anywhere, as long as the required virtual machine manager is available.

These characteristics collectively enable the creation of flexible, secure, and efficient virtualized environments, making them ideal for diverse applications, from data centers to cloud computing.