|
|
2.1 | |
Networking Terminology | |
| 2.1.1 | |
Data networks |
Data networks developed as a result of business applications that were written for microcomputers.
 At that
time microcomputers were not connected as mainframe computer terminals
were, so there was no efficient way of sharing data among multiple
microcomputers.
 It became
apparent that sharing data through the use of floppy disks was not an
efficient or cost-effective manner in which to operate businesses.
Sneakernet created multiple copies of the data. Each time a file was
modified it would have to be shared again with all other people who
needed that file. If two people modified the file and then tried to
share it, one of the sets of changes would be lost. Businesses needed
a solution that would successfully address the following three
problems:
Businesses realized that networking technology could increase productivity while saving money. Networks were added and expanded almost as rapidly as new network technologies and products were introduced. In the early 1980s networking saw a tremendous expansion, even though the early development of networking was disorganized. In the mid-1980s, the network technologies that had emerged had been created with a variety of different hardware and software implementations. Each company that created network hardware and software used its own company standards. These individual standards were developed because of competition with other companies. Consequently, many of the new network technologies were incompatible with each other. It became increasingly difficult for networks that used different specifications to communicate with each other. This often required the old network equipment to be removed to implement the new equipment. One early solution was the creation of local-area network (LAN)
standards. In a LAN system, each department of the company is a kind of electronic
island. As the use of computers in businesses grew, it soon became obvious
that even LANs were not sufficient.
What was needed was a way for information to move efficiently and
quickly, not only within a company, but also from one business to
another.
|
Because LAN standards provided an open set of guidelines for creating
network hardware and software, the equipment from different companies
could then become compatible. This allowed for stability in LAN
implementation. 
The solution was the creation of metropolitan-area networks (MANs)
and wide-area networks (WANs). Because WANs could connect user
networks over large geographic areas, it was possible for businesses
to communicate with each other across great distances. Figure
summarizes
the relative sizes of LANs and WANs.
Web Links