Assessing The Network Systems And Services Information Technology Essay

Assessing The Network Systems And Services Information Technology Essay A Virtual machine is a software application to be run in its own operating system. It is not physically exist to execute it’s a program or operating system which should be create an another environment. It is an isolated duplicate of real machine. It should be exactly act like a normal computer and carries its own virtual i.e. software based. A virtual machine is a guest and runs inside in its operating system are called a host. It’s produced to execute an instruction set unlike of host environment. A multiple virtual machines are executed by a single host environment because of they are differ from the physical resources. Fig1:- virtual machine Virtual machines are categorized into two major categories according to their use of any real machine. A system virtual machine and a process virtual machine. A system virtual machine which bears the complete system platform of a complete operating system. The main purpose to design a process virtual machine is to execute the s ingle program in the single processor. Virtual machine is act like a virtual software and virtual hardware we can run the applications same as like an physical computer and we can use the virtual hardware same as like an physical hardware components exist, also virtual machines offered a lot of advantages while compared to general physical machine. 2.1 SYSTEM VIRTUAL MACHINE System virtual machine is as well addressed as hardware virtual machine is leave the sharing of real machine resources between virtual machines in physical computer a virtual machine is executed by its own operating system. a virtual machine monitor is run on top of an operating system, a virtual machine monitor is a virtualization provided by an software layer. http://www.ntpro.nl/blog/uploads/products_vmfs_diagram.gif Fig 2:- SYSTEM VIRTUAL MACHINE The advantages of virtual machines are: Multiple operating systems are existing in the same computer and strong isolation environment is there in between them. A vi rtual machine is also a software which executed by a set of instructions that is somewhat different from a physical machine. Maintenance, disaster recovery and high availability compared to real machine. Disadvantages of virtual machines are: A virtual machine approaches the hardware indirectly so it’s a less efficient. At the same time a multiple virtual machines are executing on the same host to get a chance of unstable performance like speed of execution, its depends on work load of other virtual machine to recover that a proper techniques are used. Multiple virtual machines are running in the same physical machine called guest operating system. In that real machine often used in server consolidation, different services are executed on individual virtual machines in order to avoid interference. The main motivation of the virtual machine is to run multiple operating systems, in a single physical machine and which allowed for time sharing in between the operating systems, di fferent tasks handled by operating systems. At the introduction stage virtual memory is one of the general considerations of system virtual machine. the single-user operating system of each user providing time sharing and full virtual machine of the first system implemented by IBM’s CP/CMS.