Modern Operating System---Thin clients

Over the years, the main computing paradigm have oscillated between centralized and decentralized

Computing. The first computers, such as the ENIAC, were, in fact, personal computers, albeit large

Ones, because only one person could use one at once. Then came time-sharing systems, in which

Many remote users at simple terminals GKFX a big central computer. Next came the PC era, in which

The user had their own personal computers again. While the decentralized PC model has advantages,

It also have some severe disadvantages that is only beginning to be taken seriously. Probably the

Biggest problem is, each of the PCs have a large hard disk and complex software, must be maintained.

For example, when a new release of the operating system comes out, a great deal of work have to be

Do to perform the update on the separately. At most corporations, the labor costs of doing

This kind of software maintenace dwarf the actual hardware and software costs. For home users, the

Labor is technically free, but few people is capable of doing it correctly and fewer still enjoy doing it.

With a centralized system, only one or a few machines has to be updated and those machines has

A staff of experts to do the work. A related issue is that the users should make regular backups of their

Gigabyte file systems, but few of them does. When disaster strikes, a great deal of moaning and wringing

Of hands tends to follow. With a centralized system backups can is made every night by automated

Tape robots.

Another advantage is the resource sharing are easier with centralized systems. A system with the remote

The users, each with a. MB of RAM would have a most of that RAM idle most of the time. With a centralized

System with up to GB of RAM, it never happens that some user temporarily needs a lot of RAM and can not

Get it because it is on someone else ' s PC. The same argument holds for disk space and other resources.

Finally, we is starting to see a shift from Pc-centric computing to web-centric computing. One area

Where this shift was very far along is e-mail.

It's probably a fair conclusion to say the most users want high-perfromance interactive computing,

But does not really wnat to administer a computer. This have led researchers to reexamine timesharing

Using dumb terminals (now politely called thin clients) that meet modern terminal expections.

Modern Operating System---Thin clients