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Internet. The Internet. The Internet is the huge network of computers that links many different types of computers all over the world.
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The Internet • The Internet is the huge network of computers that links many different types of computers all over the world. • It is a network of networks that shares common mechanism for addressing (identifying) computers and a common set of communication protocols for communications between two computers on the network.
History • The Internet has its root in the ARPANET system of the Advanced Research Project Agency of the U.S. Department of Defense. • ARPANET was the first WAN and had only four sites in 1969. • The Internet evolved from the basic ideas of ARPANET for interconnecting computers and was initially used by research organizations and universities to share and exchange information.
In the 1980´s • Personal computers or terminals were connected to a server. • The server was a mainframe, or connected to a mainframe computer. • The mainframe was connected to another mainframe of the company in another location via dedicated lines. • Only large companies could afford the expense and investment in equipment.
History • In 1989, the U.S. Govt. lifted restrictions on the use of the internet and allowed it to be used for commercial purposes as well. • Since then, the Internet has rapidly grown to become the world’s largest network.
Computer classifications • Mainframes: - term for very large computers - used to handle large amount of data or complex processes - main advantage is reliability • Midrange: - medium sized, less expensive and smaller - usually a server • Micro-computer: - work stations with computing capabilities - single-users systems linked to form a network
What is a network • Series of points or nodes interconnected by communication paths • Node is a connection point for transmitting data • Network can interconnect with other networks to form global networks
Benefits of a network • Facilitates resource sharing • Provides reliability • Cost effective • Provide a powerful medium across geographical divide
Geographical Distance • Local area network (LAN): small area, share a single server • Metropolitan area network (MAN): a wider network, can bridge several LAN’s • Wide area network (WAN): a broader area covered, can include several MAN’s • Internet: a network of networks that covers the entire globe
Internet addressing system • Internet uses TCP/IP, therefore every computer on the Internet has an IP address • IP address is numerical, separated by dots • Works with DNS: - com: for commercial purposes - net: for Internet Service Providers - org: for non-profit, non-commercial groups - gov: reserved for government - mil: reserved for military - int: reserved for international organizations
Assimilation of Technology • Technology first adopted to increase efficiency – doing the same tasks faster e.g. word processing instead of typing • Technology next adopted to increase effectiveness – doing tasks not only faster but better e.g. spreadsheets transformed finance and accounting (as well as science and other fields)