Network concept

Definition of network

Network is two or more computer that are connected for sharing the data and the other tools,

Computer network also known as a combination of hardware and software and using cable as a connector for communicating between computers, to exchange information (Odom, 2004)

The good of network

·         Resources Sharing, can share data and information between system

·         Savings, can share expensive resource

·         High Reliability, can have alternative sources of supply

·         Scalability, have ability to increase system scale gradually

·         Medium Communication, for communication between personal in one system using computer network

Computer network classifications

1.    Based on transmission technology

·         Broadcast network

Having a single communication channel by all engines on the network.

·         There are 3 type of operations :

·         One resource to one destination

·         Broadcasting

·         Multicasting

 

1.    Based on distance

·         LAN (local area network)

LAN is private network in a building or a university, LAN is usually use for connecting computer in a room for sharing resource like data or printer

LAN:

ü  Local area network (in a building).

ü  Speed between 10Mbps – 100Mbps, and nowadays it has been reach 1 Gbps.

ü  Usually used by a university or an office.

ü  Have range about 1 km (based on CISCO)

    ·         MAN (metropolitan area network)

MAN (Metropolitan Area Network)

·         MAN is LAN in a big capacity using the same technology like LAN. MAN was implemented by a company for public facility, but used by individually or the other organization. The error an delay in MAN is more higher than LAN, it’s because MAN connecting so much LAN with different topology.

·         MAN is just have one or two cable and don’t have switch that usually used for arrange package the output cable.

MAN :

ü  Work space is between city.

ü  Connected LAN.

ü  Connection speed between 10 Mbps – 100 Mbps.

ü   Using satelite, Telkom, or radio wave.

ü   Range between city (based on CISCO)

 

·         WAN (wide area network)

WAN is not only a media transmission, but also some of router that connected each other. WAN is usually by a company that have office in different country. WAN was uses satellite or cable under the ocean.

 WAN:

ü  Combination of LAN and MAN.

ü  Speed between 10 Mbps – 100 Mbps

ü  Using network satelit (VSAT), radio wave

ü  Range between country.

 

Network component

There are basic component that we have to know first :

ü  Server, is computer that have a task to give service to the clien, used in a department and few user. We can divide server as from the function, which mean mainframe. Mainframe is a computer with ability for processing with very fast speed, but with expensive price. Mainframe until now is still need for processing database an complex application.

ü  Client or workstation, is computer that used by user, it can be a PC, laptop, or the other hardware that support for network. Client task is requesting service to the server.

ü  The other network component, like NIC (Network Interface Card), switch, router, cable and wireless component, etc.