Selasa, 07 April 2009


Overall computer connected to the file server in the network
referred to as a workstation. Workstation has a minimum; Card
network, network applications (network software), a cable to connect to
network, usually a workstation does not need such as Floppy
data you want in the store and can be placed on a file server. Almost all
type of computer can be used as a computer workstation.
Network Interface Cards (NICs) or Network Card
Network Card (NIC) is a device that provides media
to connect between the computer, most of the network card is the card
inernal, the network cards that plug in the expansion slot in the computer.
Some computers, such as MAC computer, using a special box
ditancapkan to the serial port or SCSI port computer. On the computer
there is slot for notebook network card which is called a PCMCIA slot.
Network cards which are used at this time are: network card
Ethernet, LocalTalk connectors, and Token Ring network card. That at this time
Ethernet is a popular use, followed by Token Ring, and LocalTalk,
Ethernet Card / Ethernet Network Card
Ethernet network cards are usually purchased with a separate computer, unless
such as the Macintosh computer that already include a network card ethernet
therein. Network card ethernet port has provided a general connection
Koaksial for cable or twisted pair cable, if cable is designed to
koaksial konenektorya is BNC, and when the cable is designed for twisted pair
it will have a RJ-45 connectors. Some cards also sometimes ethernet network
have AUI connector. All that connect with the koaksial, twisted
pair, or with fiber optic cable.
Figure Ethernet Network Card
From Top to bottom:
RJ-45 connectors, connectors AUI, and BNC connectors


The protocol is the rules that set the main communication
among several computers in a network, including the rules
in the instructions that apply to the ways or methods of access
a network, physical topology, cable types and speed of data transfer.
Protocol-Protocol that is known is as follows:
1. Ethernet
2. Local Talk
3. Token Ring
5. ATM

Minggu, 05 April 2009


There are many networks in the world, often with the hardware and
software is different. People connected to the network often
hope to be able to communication with other people connected to the
other network. Desire such as this requires a relationship between network which are often different and not compatible. Sometimes the machine GATEWAY called as a translator between the network that are not compatible. Collection of networks that are connected or called INTERNETWORK, INTERNET. INTERNET general form of the collection is from the LAN connected by WAN.


Covers a wide geographical area, often include state or
continents. WAN consists of a collection of machines that aim to run
programs (applications) user. This machine is called HOST. HOST
connected by a communication subnet or subnet is called.
Subnet is the task of carrying messages from one host to another host. In the
most of the WAN subnet consists of 2 components: cables and transmission
switching element.
Relationship between host-host with a subnet


LAN version is bigger and usually use a technology
the same LAN. MAN is able to support data and voice, and even
can be related to the cable television network. MAN has only
a cable or two and do not have a switching element, the
function to set the package through some cable output.
Direction of flow on the Bus A
Bus A
Direction of flow on the Bus B


LAN: connecting personal computers in the office
perpusahaan, factory or campus: LAN can be distinguished from the type of
other network based on 3 characteristics: size, technology, transmission
and network topology.
Type of LAN topology broadcast: BUS (USB linier)
Type of LAN topology broadcast: RING
Type of LAN topology point-to-point: STAR


Communication was initially dependent on the transport: roads between cities, between province / state and inter-country / continent. Then communication can occur through long-distance telegraph (1844), telephone (1867), radio waves elektromagnetik (1889), commercial radio (1906), television broadcast (1931), and then through television, the world so much smaller because people can see and get information about going on in other parts of the world. In telecommunications, the information delivered through the signal. Signals have two types:

1. Digital: specifically refer to the information that was represented by two
state 0 or 1. Digital data are sent to the two conditions are represented
namely 0 and 1.
2. Analog: the signal is constant with variations in strength and quality.
For example, sound, light and temperature that can change and strength
quality. Analog data is sent in the form of a sustainable, signal
development in the form of electrical waves
Television, radio and telephone is a telecommunications technology that uses analog signals, while using the computer for digital signal transfer
information. However, when this signal is also used for digital voice, image and combination of both. On the other hand, the computer that originally used as a calculator and data processing, is used as a means of communication since the network computer.