This preview shows page 1. Sign up to view the full content.
Unformatted text preview: users to simultaneously use the system through the user terminals, their
operating systems support multiprogramming with timesharing so that all the users
get good response time and an illusion that their jobs are being attended to by the
5. Output devices. The user terminals serve the purpose of soft copy output
devices. However, for hard copy outputs, «a mainframe system usually has several
printers and one or more plotters connected to the back-end computer. Different
printers may be of different print speeds and different print qualities. Plotters are
used to produce large, high-precision hard copies of graphs, charts, blueprints, and
drawings. These output devices are also located in the user room so that they are
accessible to the users for taking their outputs.
It is unlikely that you would find two mainframe systems configured in exactly the
same way. The configuration of a mainframe system depends a lot on the type of
usage and the kind of users it is meant for. The example of Figure 20.4 is just one
Mainframe systems are much bigger and several times more expensive than
workstations. A typical mainframe system looks like a row of large file cabinets
and needs a large room with closely monitored humidity and temperature. A
mainframe system may cost anywhere from a few tens of lakhs to a few crores of
rupees depending on the configuration. A mainframe system having smaller
configuration (slower host and subordinate computers, lesser storage space, and
fewer user terminals) is often referred to as a minicomputer system. However, there is no well-defined boundary for differentiating between the two. Two major
vendors of mainframe systems are IBM and DEC.
Supercomputers are the most powerful and most expensive computers available at
a given time. They are primarily used for processing complex scientific
applications that require enormous processing power. For example, scientists build
models of complex processes and simulate the processes on a supercomput...
View Full Document
This document was uploaded on 04/07/2014.
- Spring '14