Computer network

Computer network is a system consisting of computers and other network devices that work together to achieve a common goal.

The purpose of the computer network are:
• Sharing the resources: for example, shared use of printers, CPUs, memory, hard drive
• Communication: eg electronic mail, instant messaging, chat
• Access to information: for example web browsing
In order to achieve the same goal, each part of the computer network and provide service request (service). Party requesting the service is called a client (client) and that provide services called the servant (the server). This architecture is called client-server systems, and is used in almost all computer network applications.

Classification Based on the scale:
• Personal Area Network (PAN)
• Campus Area Network (CAN)
• Local Area Network (LAN): a computer network that connects a computer to another computer with a limited distance.
• Metropolitant Area Network (MAN): principle the same as LAN, only the larger distance, ie 10-50 km.
• Wide Area Network (WAN): the distance between cities, countries, and continents. This is the same with the Internet.
• Global Area Network (GAN)

Based on the function: Basically every computer network is functioning as a client and server. But there is a network that has a dedicated computer as a server and the other as a client. There is also a computer that has no special function as a server only. Therefore, based on their function there are two types of computer networks:


• Client-server
Network is the computer with a dedicated computer as a server. A service / service can be provided by a computer or more. An example is a domain like www.detik.com lots served by the web server computer. Or it could be a lot of service / services provided by a single computer. Examples are jtk.polban.ac.id server that is a multi-service computer with the mail servers, web servers, file servers, database servers and others.

• Peer-to-peer
Namely computer networks where each host can be a server and also a client simultaneously. For example in the file sharing between computers on the Windows Network Neighborhood Network have 5 computers (we give the name of A, B, C, D and E) that provide access rights to the files they have. At one point A to access the file share of B named data_nilai.xls and also gives access to the file soal_uas.doc C. When accessing a file from B then A serves as a client and as a give file access to C then A serves as a server. Both functions were performed by the same A network like this is called peer to peer.

Based on network topology, computer networks can be divided into:
• bus topology
• star topology
• ring topology
• mesh topology
• Topology tree
• Linear topology

Based on the criteria, the computer network can be divided into 4, namely:
1. Based on the distribution of sources of information / data
- This network centralized network consisting of Client and server computers which Client computer that serves as an intermediary to access sources of information / data derived from a single server computer
- Network is a combination of several distributed centralized network so that there are several computer servers that are interconnected with the Client to form a specific network system.

2. Based on geographic coverage can be divided into:
- Network LAN is a network that connects 2 computers or more in coverage such as laboratories, offices, and in 1 cafe.
- MAN network is a network that includes a big city and its local area. Examples of local telephone networks, cellular telephone systems, as well as some ISPs relay network Internet.
- Network WAN is a network with coverage throughout the world. PT network example. Telkom, PT. Indosat, as well as GSM networks such as Cellular Satelindo, Telkomsel, and much more.

3. Based on the roles and relationships of each computer in the data processing.
- Network Client-Server In this network there are 1 or more server computers and client computers. Computers will be computers or servers to client computers and altered through the protocol software on the network. Client computer as an intermediary to be able to access data on a server computer and the server computer to provide information needed by the client computer.
-Network Peer-to-peer in this network there are no client computer or server computer because all computers can make sending and receiving information so that all computers function as clients as well as a server.

4. Based on the data transmission media
- Wired Network (Wired Network) In this network, to connect one computer to another computer in the form of necessary liaison network cable. Function in the network cable to send information in the form of electrical signals between the network computer.

- Wireless Network (Wireless Network) is a network with the medium of electromagnetic waves. In this network does not need a cable to connect between computers that use electromagnetic waves to send signals between the computer information network

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Indonesian Internet beginning

Indonesian Internet history began in the early 1990s, when it w network: the Internet in Indonesia is better known as the community network, where the spirit of cooperation, mutual assistance of family & a very warm and was among the perpetrators. The atmosphere was quite different from Indonesia on Internet development that was more commercial and individual in some activities, especially involving Internet commerce.

Rahmat M. Samik-Ibrahim, Suryono Adisoemarta, Mohammed Ihsan, Robby Soebiakto, Putu Surya, Firman Siregar, Adi Indrayanto, w: Onno W. Purbo are some legendary names in the beginning of Internet development in Indonesia w: up to 1992 w: 1994. Each has contributed personal expertise and dedication in building a historical footage w: computer network in Indonesia.

The writings of the existence of the Internet network in Indonesia can be viewed in several articles in print media such as w: KOMPAS titled "low-cost computer network using the radio" at the end of w: w 1990 and earlier: 1991. Also some short articles on the w: Electronic Magazine Association of Electrical Mahsiswa w: w ITB in the year: 1989.

Inspiration early writings coming from Indonesia Internet activities in w: amateur radio, especially in the Amateur Radio Club (ARC) w: w ITB in the year: 1986. Capital flight w: Transceiver w: w HF: Kenwood TS430 SSB's Harya Sudirapratama (YC1HCE) with the Apple II computer owned by Onno W. Purbo (YC1DAV) about a dozen young children w: ITB as Harya Sudirapratama (YC1HCE), J. Tjandra Pramudito (YB3NR), Suryono Adisoemarta (N5SNN) with w: Onno W. Purbo, studied at the Senior Amateur Radio as Robby Soebiakto (YB1BG), Achmad Zaini (YB1HR), Joshua (YB2SV), in the 40m band. Robby is an expert Soebiakto among radio amateurs in Indonesia, particularly for data communications w: packet radio which then pushed in the direction w: TCP / IP, packet radio technology w: TCP / IP which was adopted by fellow w: BPPT, w: LAPAN, w: UI, and w: ITB which later become the foundation in the year PaguyubanNet w :1992-w: 1994. Robby has been coordinated w Soebiakto: The first IP from w: AMPR-net (Amateur Packet Radio Network) which is known as the Internet domain name and IP AMPR.ORG 44,132. Since w: 2000 w: AMPR-net by Indonesia in coordination w: Onno W. Purbo (YC0MLC). Coordination and its activity requires one to become a member w: ORARI and in coordination with ORARI mailing list, like, orari-news@yahoogroups.com.


In the 1986-1987 year beginning development of packet radio network in Indonesia, Soebiakto Robby is a pioneer among the perpetrators of amateur radio network linking Indonesia amateur Bulletin Board System (w: BBS) is an e-mail network of store and forward that link the many "servers" w : BBS radio amateurs around the world for e-mail can proceed smoothly. At the beginning of w: communication between w 1990: Onno W. Purbo, who had been in Canada with YC1DAV/VE3 calls with fellow radio amateurs in Indonesia is carried out through this network of radio amateurs.

With the equipment PC / XT and w: 2 meter walkie talkies, communications between the Indonesia-Canada continues smoothly through a network of radio amateurs. Robby Soebiakto amateur built the satellite gateway at his home in Labu via satellites w: OSCAR's amateur radio and then make further communication faster between Indonesia and Canada. Knowledge transfer and gradually evolved through a network of radio amateurs.

Mohammed Ihsan is a staff researcher at the w: LAPAN Bungur Ranch not far from w: Bogor is in the early 1990s supported by the leadership Mother Adrianti in cooperation with w: DLR (German his NASA) tried to develop a computer network using packet radio technology band 70cm & 2m. Network is known as w: w JASIPAKTA with support: DLR Germany. W Protocols: TCP / IP protocol running on top w: AX.25 packet radio on infrastructure. Muhammad Ehsan operates relay link between w: ITB in Bandung with the existing Internet gateway in the w: w in BPPT :1993-w: 1998.

Mr. Firman Siregar was one of the motor in w: BPPT that operates the gateway w: packet radio 70cm band worked on in the year 1993 to 1998-an. 386 simple PC running the program w: NOS on the operating system w: DOS is used as a gateway packet radio w: TCP / IP. w: IPTEKNET still in the very early stages of development of communication channels to the Internet are still using the protocol w: X.25 network via Data Communication System Package (w: Public switched data network) related to the gateway at the w: DLR Germany.

Putu Surya a name that stuck with PUSDATA development lead times DEPRIN time you run Ariwibowo Tungki Minister w: pusdata.dprin.go.id BBS. In the early days of development w: BBS Mr. Putu was instrumental in building an e-mail users, especially in Jakarta, Mr. Putu very fortunate to have a minister Mr. Tungki the "maniac" w: IT and impressive than Mr. Tungki he would answer his own e-mail. Perhaps Mr. Tungki is Indonesia's first minister to answer e-mail itself.

Suryono Adisoemarta N5SNN at the end of 1992 returned to Indonesia, the opportunity is not missed by members of the Amateur Radio Club (ARC) w: ITB as Suhardiman Basuki, Aulia K. Arief, Arman Hazairin supported by Adi Indrayanto to try to develop a gateway w: packet radio at w: ITB. Starting with the spirit & capitalize PC 286 marks perhaps w: ITB is the poorest institutions are desperate for work in PaguyubanNet network. Other colleagues such as w: UI, w: BPPT, w: LAPAN, PUSDATA DEPRIN is the first institution related to the network in the 1990s they have the facilities much better than w: ITB. In w: ITB modem w: a packet radio Terminal Node Controller (w: TNC) is an equipment loan from Muhammad Ehsan from w: LAPAN.

Suryono Adisoemarta N5SNN own when I was taking S2nya college at the University of Texax in Austin, Texas, to connect the TCP / IP Amateur Austin to the Internet gateway for the first time, at the Chemical and Petroleum Engineering University of Texas, Ameria States, so that the community Amateur Radio TCP / Austin IP network can connect to TCP / IP all over the world and even allow direct access to the Internet by using a radio amateur (Lim, 2005). Knowledge is what then was applied in packet radio development in the ITB.

Starting from the technology w: packet radio 1200w: bps, w: ITB was developed in 1995's get connection w: 14.4Kbps leased line to the w: RISTI w: Telkom as part of the w: Internet access remains IPTEKNET provided free of charge to colleagues the other. September 1996 was a year of transition for the w: ITB, because the association w: ITB Asia with the research network Internet Interconnection Initiatives (w: AI3) to get to Japan 1.5Mbps bandwidth are kept together with a connection to Telkomnet & IIX for 2Mbps. w: ITB eventually become one of the most important part of the Indonesian education network calling itself w: AI3 Indonesia linking 25 + education institutions in Indonesia in the years 1997 to 1998-an.

This educational network is not only a monopoly w: ITB course, other educational networks bigger is the network w: CMS are dibawahi w: Dikmenjur (dikmenjur@egroups.com). In the year 2006, practically there are more than 4000 schools in Indonesia that are connected to the Internet mostly w: SMK.
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Mampukah Manusia Mengendalikan Technologi Seutuhnya. (English Version)

The accident could not have predicted all that happened beyond our control as humans.
Life is all there is the good and bad, we are only able to experience the life of this well even if the reality does not match the reality

is nothing new when the aircraft fell uncontrollable, almost all the airlines may be experiencing the same thing, but that's different is how the result of the disaster.




Airline aircraft Turkies Wednesday (25 / 2) fall in the Amsterdam Schipol Airport, the airport is popular with the strict regulations of the plane.

aircraft is split into 3 even parts for its aircraft engines are throwing up to 100 meters from the location of the incident and the aircraft tail separated from the fuselage about three meters. The muzzle nyungsep aircraft in the area is empty.

while the results for the investigation said there is no victim killed in the incident plane experienced Turkish Airlines Boeing 737-800. Aircraft numbered flight TK1951 was broken when three landed at Schiphol Airport at around 10 o'clock local time.
According to information, the unlucky plane carrying 135 passengers from Istanbul.

Despite three broken parts from the head, body, and the cockpit, the plane did not burn. About 50 passengers are injured in the incident.


This small example of the human face does not freeze the natural result of technology that is made, but people can prevent this by performing maintenance, repairs and supervision. Sometimes we are too dependent to technology, technology that can actually destroy mankind if not ready to progress with technology in the era of seconds to minutes for the progress.

Reference : Kompas.com
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