Computer Science Network

Network of computer science - computer network is very necessary to be studied below are some things that might be useful for you the money want to know what a computer network and how it works

Communication initially relied on transportation: roads between cities, between provinces / states and between countries / continents. Then communication can occur remotely via the telegraph (1844), telephone (1867), electromagnetic radio waves (1889), commercial radio (1906), Television Broadcasts (1931), and then through television, the world became smaller because people can learn and gain information about that happening in other parts of the world. In telecommunications, the information conveyed through the signal. There are two kinds of signals:


Kinds of kinds of signals

1. Digital: specifically refers to information that is represented by two
state 0 or 1. Digital data is sent with only two conditions are represented by 0 and 1.

2. Analog: continuous signal by varying the strength and quality. Eg sound, light and temperature which can change its strength and quality. Analog data is sent in the form of a sustainable, continuous electrical signal waveform TV, telephone and radio are telecommunications technology that uses analog signals, while computers use digital signals to transfer information. However, the current digital signal is also used for voice, picture and combination thereof.

On the other hand, the computer that was originally used as calculating machines and data processing, is used as a means of communication since the computer networks. Computer network computer network is a set of computer numerous separate but interrelated in performing their duties. Two computers for instance say if both are mutually connected
exchanging information. Forms of connection can be through: copper wire, fiber optic, microwave, satellite communications.

In a computer network: The user must explicitly:
- Entering or log in to a machine
- Gave the task of remote
- Move files
- Handle themselves in general throughout the network management

Computer networks became important to humans and their organizations because the computer network has a goal that is beneficial to them. Computer networks objective is to:

1. resource sharing / sharing the source: all programs, equipment and data that can be used by any person on the network without
influenced the location of the source and the user. For example: Staff Academic BUREAU send new students to the library list in the form of a printout with the printer to print directly from computers in the library of academic BUREAU. Or get directly opposite the library staff of new students a list of files stored on your computer BUREAU academic staff.

2. high reliability / high reliability: availability of alternative sources whenever necessary. For example in banking or military applications, if one machine does not work, the performance of the organization is not disturbed because the other machine has the same source.

3. save money: build a network with small computers cheaper than using a mainframe. Data
stored in a computer that acts as a server and other computers that use the data to act as a client. This shape is called client-server.

4. scalability / scalability: increasing performance by adding
server or client computer easily without disturbing the performance
computer server or an existing client computer first.

5. medium of communication: possible cooperation among the people far from each other through either a computer network to exchange data or communicate.

6. broad access to information: access and obtain information from remote

7. communications person-to-man: used to communicate from one
person to person

8. interactive entertainment

In the introduction to computer networks, discussion of views from two aspects:
hardware and software. In recognition of hardware including type of transmission, and other forms of computer network or topology. While the discussion will include the composition of its software protocols and data travel from one computer to another computer in a network

Hardware: Computer Network Classification There are two classifications are differentiated based on computer networks and distance transmission technology.

1. Transmission Technology
Broadly speaking there are two types of transmission technology:
a. broadcast network
has a single communication channel shared by
all the existing machines on the network. The messages are small,
called a packet and delivered by a machine and then accepted by
other machines. Section contains a description of the address on the package
about to whom the package is intended. When you receive a package, the machine will check the address, if the package to the machine, the machine will process the packet. If not then ignore the machine.

b. network point-to-point
consists of several individual pairs of connection machines. For
go from one source to the destination, a packet on the network of this type may be through one or more intermediary machines.
Often must go through many routes (routes) that may be different
distance. Therefore, the routing algorithm plays an important role in
network point-to-point. As a general grip (although many exceptions), smaller networks are geographically localized and tend to use broadcasting, while the larger networks generally use a point-to-point.

2. Distance
Distance is important as a measure of classification because it required different techniques for different distances. The following table describes the relationship between distance and the processor is placed in the same place

Here is limited and briefly described a simple LAN, MAN, WAN and Internet.

a. LAN: connecting personal computers in the office
company, factory or campus: LAN can be distinguished from type
other networks based on three characteristics: size, transmission technology
and network topology

b. MAN
Is a larger size version of the LAN and normally uses technology
The same with the LAN. MAN capable of supporting voice and data, and can even connect with a cable television network. MAN has

c. WAN
Covering a wide geographical area, often include state or
continent. WAN consists of a collection of machines that aims to implement programs (applications) user. This machine is called HOST. HOST linked by a communication subnet or simply called SUBNET. Subnet task was to carry messages from one host to another host. In most of the WAN subnet consists of two components: the cable transmission and switching elements

d. Internet
There are many networks in the world, often with hardware and software are different. People who are connected to the network often expect to be able to communicate with others who connect to other networks. This desire requires the relationship between networks that are often not compatible and different. Sometimes using a machine called a GATEWAY as a translator between incompatible networks. Collection of network-connected internetwork or Internet called. INTERNET common forms is a collection of LANs connected by WAN