NETWORK COMPUTERS

N e T w o R k    C o M P u T E r S

THE INTERNET LINKS MILLIONS of computers world wide, and anybody with a personal computer(PC) and basic communication tools can be come  a part of it. The ever-expanding "NET" is becoming a vital resource for business, education and entertainment. The huge multimedia data base of the world wide web, which is one aspect of the  net, is so sophisticated that users can be "meet" in "virtual worlds". As the net evolves, so new ways of computing are made possible. Network computing is one possible development which promises greater compatibility and efficiency than personal computing. At present, the net consists mainly of PCs with large amounts of processing power and disk space called ("fat client computers")  connected to servers (other computer that distribute data). The idea behind network computing is to replace the PC, or fat client, with a network computer (NC) or "thin client". A thin client computer has a processor like a PC, but less memory and so no disk storage, and so is much cheaper. Instead of storing application programs and data on a local hard disk (as a PC does), an NC simply downloads programs and data from a server into its RAM as needed. Network computing promises economies of scale  and centralization, since all the data is stored on a few servers and any software developments that need to be made apply to these servers only.

THIN CLIENT COMPUTER: The thin client NC is halfway between a PC and a  dumb terminal, used on mainframe computers. A dumb terminal consists only of a keyboard and a monitor all processing and data storage is carried out centrally by the main frame. Like dumb terminals NCs have no local disk storage, but like PCs, they do have a processor. In addition to being smaller and cheaper than PCs, NCs should be more reliable, since they do not  have complex peripherals with moving parts, such as disk drives.


DISTRIBUTED COMPUTING: Net work computing has been made possible because the computer industry has agreed hardware and software standards, including a new language, Java. When a thin client-or a fat client acting as Java station-is switched on, its basic boot-up software connects to a network and downloads the full Java operating system. The user can then download Java application programs ( called applets) and data required, paying any fee with a smart card. High-speed links between client and server mean that processing task can be distributed between computers, so the applets can be relatively small. In network computing, the main burden falls not on the client machines but on the network. Whether the present Internet infrastructure(phones lines,cables,etc) has the required capacity, speed and reliability to support network computing remains to be seen.

VIRTUAL WORLDS ON THE NET

 The World Wide Web has brought multi media graphics, animations, sound and hyper linking-to the Internet. The virtual world wide web (VWWW), with virtual environments, is a further development where users can interact graphically with each other. Typically VWWW environments are spread across sites on the net and on a CD-ROM. The basic program runs from the CD, but "interactions" between users occur at VWWW sites.

 All three-dimensional virtual worlds must first be rendered in ink, as shown below, after which the illustrations are digitized by a computer.

 When a user logs on to a virtual world, he or she chooses a graphical identity; this is how they will appear on other users screens around the world. These virtual people scroll around and meet in virtual streets-although the real users might be thousands of miles apart.

 Some features of a virtual world are purely fictional, like a user's graphical identity, while the streets or environment may be based on a real place. But, as in the real Paris, you can "walk" into a store, shop using your real credit card, and have the real goods delivered.