Question

. Virtualization simplifies the use of resources, isolates users from one another, supports replication and mobility, but exacts a price in terms of performance and cost. Analyze each one of these aspects for: (i) memory virtualization, (ii) processor virtualization, and (iii) virtualization of a communication channel.

Answer 1

Answer:

In computing, virtualisation is defined as the processing of creating an intangible but electronic and functional version of a device or resource, such as a server, storage device, network or even an operating system where the framework divides the resource into one or more execution environments

(i) Memory Virtualisation

Memory virtualisation is seen as virtual memory, or swap, on servers and workstations.

It enhances performance by providing greater memory capacity, without the expense of adding main memory. Instead, a portion of a disk drive becomes an extension of main memory.

Importance of Virtual Memory

• When the computer runs out of Random Access Memory, it writes what it needs to remember to the hard disk in a swap file as virtual memory.
• In windows environment, if the computer requires more memory or RAM, then it is installed in the system to run a program , it uses a small section of hard drive for this purpose. A 16 MB program can run in 4 MB space by carefully choosing which 4 MB to keep in memory at each instance, with pieces of the program being swapped between disk and memory as needed.    

(II) Processor Virtualisation

CPU virtualisation involves a single CPU acting as if it were multiple separate CPUs on the same logic board within the same operating system/computer.

Usually this is done to enable the user to run multiple different operating systems on one machine at the same time. CPU virtualisation emphasises performance and runs directly on the available CPUs whenever possible. The underlying physical resources are used whenever possible and the virtualisation layer runs instructions only as needed to make virtual machines operate as if they were running directly on a physical machine.

When CPU contention occurs, the operating systems host time-slices the physical processors across all virtual machines so each virtual machine runs as if it has its specified number of virtual processors.

There is usually a performance price to pay when running a virtual processor even on an Enterprise Server environment.

(III) Virtualisation of Communication Channel

Virtual communication is defined as a mode of communication that includes the use of technology - audio and video to communicate with people who are not physically present in front of us. People can be in the next room, other floor, in neighbourhood or even miles away.

Implication of Virtualised Communication Channel

Fast: Instant messaging applications have enabled us communicate in real time as well as exchange valuable information. With Instant messaging applications or web conferencing tool, we can share news or information across the globe in seconds. This is highly valuable in times of of a disaster or collection of real time data.

Cost effective: Apart from been quickly, virtual communication also saves a lot money. Rather travelling miles, we can talk by initiating a video call. In a professional environment, it saves a lot of time and money.

Secure: Most of the texts we message via instant messaging application or web conferencing tool are encrypted, therefore no fear of our messages being misused.

Cheers!