CHAPTER CONTENT
DIGITAL SUBSCRIBER LINE
WORLD WIDE WEB
INTERNET
LOCAL AREA NETWORK
WIDE AREA NETWORK
HYPERLINK
DISITAL SUBSCRIBER LINE
A telecommunications technology for providing high-speed transmission to subscrivers over theexisting copper wire twisted-pair local loop between the customer premises and the telco's central office (CO). The Disital Subscriber Line (DSL) technology was designed to provide high-speed data and video-on-demand service to subscribers at speeds much faster than Integranted Services Digital Network (ISDN). The essential advantage of using DSL is that it allows much faster data transmission rates over existing copper local loop telephone lines than traditional modems.
WORLD WIDE WEB
The World Wide Web, or simply "the Web" is a global information system that is the fastest growing area of the Internet. In other words World Wide Web is a series of servers that are interconnected through hypertext. Hypertext is a method of presenting information in which certain text are highlighted, that, when selected, dispalys more information on that particular topic.
The Web, like all Internet services, is based on the interaction and transfer of data between special server computers (Web servers) and your PC (using Web browser software such as Internet Explorer from Microsoft).
INTERNET
Internet is an interconnection between several computers of different types belonging to various networs all over the world. It is an network of networks. Millions of people throughout the world use Internet to share information and ideas, to search information to share information on any topic, etc. It grown into an important infrastructure supporting wide-spread, multi-disciplinary community. This community now consists of students, scients and researchers, large corporations, non-profit organizations, government agencies, and individual consumers.
Internet is a computer-based world wide information network. Internet is the network of computers connected with one another all over the world.
LOCAL AREA NETWORK
LAN is a group of computers located in the same room, on the same floor, or in the same building that are connected to form a single computer network. Local area networks (LANs) allow users to share storage devices, printers, applications, data and other network resources. They are limited to a specific geographical area., usually less than one kilometer in diameter.
WIDE AREA NETWORK
Wide Area Network is a digital communication system which interconnects different sites, computer installations and user treminals. It may also enable LANs to communicate with each other.This type of network may be developed to operate natiowide or worldwide. The transmission media used in WANs are normally public systems such as telephone lines, microwave link and satellite links.
WAN is used to interconnect LANs which may be at opposite sides of a country or located around the earth's globe.
HYPERLINK
Hyperlinks, or links are Web navigation elements that allows you to move, or navigate, between Web pages. They also allow you to doenload audio, video, and other types of multimedia files. Web pages accessed via a link may reside at the same Web site as the source link or at another site any where on the Web.
There are three types of hyperlinks.
- text hyperlinks
- image hyperlinks
- image maps (containing multiple hyperlinks)
Functionally, all the three categories of hyperlinks are identical. Text hyperlinks are generally denoted in blue colour and underlined, while image hyperlinks and maps are indicated by a blue coloured border. In all the three cases, the mouse pointer will change from an arrow to a pointing hand when it passes over a hyperlink.