The background section provides the reader with some information on the following: virtualisation and cloud computing; and the use of virtualisation for higher education, to assist the readers understanding of how virtualisation can be realised.
Virtualisation and Cloud Computing
This section explains how Terminal Services and Thin Clients are used to realise virtualisation.
Figure 1. shows how Terminal services can provide the same operating system to many work stations in the same laboratory. Alternatively, terminal services can provide each individual user with the operating system they specifically require, be it an Apple, Windows or Linux environment. Terminal Services are hosted by a terminal server to provide multiple client sessions simultaneously in an attempt to reduce the cost of providing information technology services. Terminal Services (TS) refers to software installed on a server which provides a view into the image which will be displayed on the thin clients for student use. “Server applications are required to operate continuously and remain highly responsive to frequent client requests” (Liu, Wang, Li, & Gaudiot, 2011, p. 452).
Figure 1. Virtualisation: Terminal services
A thin client does not contain the same central processing unit, hard drive, random access memory and data stores as a desktop personal computer, instead thin clients rely on host servers to provide the computing resources users require via the web. Due to reduced functionality thin clients are cheaper to purchase than desktops. The use of thin clients for student use enables the partitioning of servers to create virtual machines which appear to the user as powerful computer devices. “The central server in a thin client network is often called the ‘terminal server’. It is a powerful, high specification machine, capable of handling a large number of logged-in clients” (NCTE, 2008, p. 19).
Figure 2. shows how operating systems, applications and storage spaces contained on centrally stored servers can be accessed by mobile phones, thin clients, desktops, laptops and tablets. Cloud computing implies the delivery of computing services over a network (Internet or Intranet), to provide Information Technology as a service (ITaaS).