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Computer network
In the 1950s when the type of computer began to grow until the creation of a super computer, then a computer had to serve several terminals. (See Figure 1.4) For this reason, the concept of time-based process distribution was discovered, known as TSS (Time Sharing System), and for the first time a computer network was formed at the application layer.
In the TSS system several terminals are connected to a host computer. In the TSS process, a combination of computer technology and telecommunications technology began to appear, which initially developed separately.
In 1957 the Advanced Research Projects Agency (ARPA) was formed by the Department of Defense (DoD) USA, 1967 the initial design of the ARPANET was published and in 1969 the DoD carried out the development of the ARPANET by conducting research to connect a number of computers to form an organic network (this program is known as ARPANET).
● A Brief History of the Internet and the Web
1957: Advanced Research Projects Agency (ARPA) is formed by the US Department of Defense (DoD).
1959: Len Kleinrock writes a paper on packet switching.
1967: The initial designs of the ARPANET are published.
1969: DoD launches ARPANET development
1970: ARPANET begins to use the Network Control Protocol (NCP)
1972: The InterNetworking Working Group (INWG) was formed to promote mutually agreed standards. Specifications from telnet, proposed.
1973: The idea of ethernet is elaborated in Bob Metcalfe’s PhD thesis. A specification for File Transfer, RFC 454, is proposed.
1974: The design of TCP/IP is described in detail by Vint Cerf and Bob Kahn in “A Protocol for Packet Network Intercommunication”.
1982: TCP/IP becomes the protocol for the ARPANET and it is specified by the DoD.
1992: The number of Internet hosts exceeds 1,000,000. Tim Berners Lee invented the editor and browser program. The University of Nevada issued the Veronica system. A WWW browser called Viola was launched by Pei Wei and distributed with CERN WWW.
1993: NSF created InterNIC to run Internet services such as domain registration. The first version of Mosaic (for X Window) developed by Marc Andreesen was released by the NCSA White House Online. The National Information Infrastructure Act passed and the United States government began to be more serious in handling the Website.
1994: PizzaHut online, is the first example of a commercial Internet application. Spam mail became a big case after a legal institution called Canter & Siegel spread mail around the world about services to get “green cards”. First Virtual runs the first “CyberBank”. In 1994, Yahoo! founded and also the year Netscape Navigator 1.0 was born.
1995: Compuserve, America Online, and Prodiy begin providing Internet access services. Marc Andreesen’s company, Netscape Communication Corporation, goes public and becomes the 3rd highest price Initial Public Offering (IPO) share on the NASDAQ. NFS no longer makes domain registration free. Domain users start paying for a domain that is used and hosted on the internet.
● Purpose / Benefits of Computer Networking
The benefits of computer networks for users can be grouped into two, namely: for company needs, and networks for the public.
The main purpose of building a network in a company
Resource sharing which aims to make all programs, equipment, especially data can be used by everyone on the network
Saving Money (Savings money/budget): Shared devices and data will create considerable budget savings, because there is no need to buy new devices to be installed in each computer unit
High reliability: Integrated Office Management Information System or One-Stop Service System with client-server, internet and intranet technology can be applied to computer networks, so that they can provide reliable, fast and accurate services according to needs and expectations.
●Benefits of computer networks for the public:
Computer networks will provide different services to users at home compared to services provided to companies. There are three main things that make computer networks attractive to individuals, namely:
access to information located elsewhere (such as access to the latest news, e-government info, e-commerce or e-business, all up to date).
person to person communication (such as e-mail, chat, video conferene etc.).
interactive entertainment (such as watching tv shows on-line, radio streaming, downloading movies or songs, etc.).
● Social problems caused by computer networks (internet)
The use of networks by the wider community will cause inevitable social, ethical, political, and economic problems. The internet has entered all corners of people’s lives, everyone can use it regardless of social status, age, and gender.
The use of the internet will not cause problems as long as the subject is limited to technical topics, education or hobbies, as well as things that are still within the limits of the norms of life, but difficulties begin to arise when a site on the internet has a topic that really attracts people’s attention, such as political opposition, religion, sex, etc.
This computer/internet network connection will also cause serious economic problems if the technology is used by certain parties who want to take personal advantage but harm other parties, such as carding activities, illegal downloading of commercial software, etc.
The pictures posted on internet sites may be normal for some people, but very disturbing for others (because it can cause SARA problems).
In addition, the form of messages is not limited to just textual messages. High-resolution color photos and even short video clips can now be easily distributed over computer networks.
Some people can be indifferent, but for others the posting of certain material (eg pornography) is unacceptable.
● Network types
In general, computer networks are divided into 3 types of networks, namely:
●Local Area Network (LAN)
A LAN, is a network that is limited by a relatively small area, generally limited by an environmental area, such as an office in a building, or each room in a school. Usually the distance between nodes is no more than about 200 m.
● Metropolitan Area Network (MAN)
A MAN, usually covers an area larger than a LAN, for example between buildings in an area (region such as a province or state). In this case the network connects several small networks into a larger area environment, for example: a network of several branch offices of a bank in a large city that are connected to one another.
●Wide Area Network (WAN)
Wide Area Network (WAN) is a network that usually already uses wireless media, satellite facilities or fiber optic cables, because its coverage is wider, not only covering one city or between cities in an area, but starting to reach the area/area of authority of another country.
For example, the City Bank office computer network in Indonesia or in other countries, which are interconnected, ATM Master Card, Visa Card or Cirrus networks spread throughout the world and others.
Usually WAN is more complicated and very complex when compared to LAN or MAN. Using many means to connect between LAN and WAN into global communications such as the internet, however between LAN, MAN and WAN are not much different in some respects, only the scope of the area is different from one another.