Artikel

L A N

 ( Lokal Area Network )

A.    Lokal Area Network (LAN)

LAN (Local Area Network) is a network the limitedness in local or distance area. This Network used many in one connective companies between department in one building. LAN differ from WAN (Wide Area Network) that is LAN can use cable for the transmission of his data (as link). WAN still require to use additional communications paths for example telephone, satellite and others. In general topology of LAN is network star or bus of network.

Data transmission in LAN have speed which different each other and can be grouped as following :

1.      High Speed Network.

High Speed Network is network having data transmission capacities bigger than 20 MBPS which was usually applied in LAN for the mainframe of computer the bigness for example Loosely Coupled Network ( Control Data of Coorporation ) Hyperchannel ( Network System Coorporation ).

2.      Medium Speed Network.

Medium Speed Network is network having data transmission capacities between from 1 MBPS - 20 MBPS which was usually applied for the mainframe of computer the smallness or mini computer for example Ethernet developed by Xerox, ARC Net developed by Datapoint Coorporation.

3.      Low Speed PC Network.

Low Speed PC Network is network having data transmission capacities smaller than 1 MBPS was usually applied for the personal of computer for example Omninet with bus topology of network by Corvus System able to connect computer which is one with other computer to together to use harddisk and peripheral of other device.

LAN is usually used to join some micro computer in companies. Server can in the form of micro computer or workstation system. Ad for the server or mini computer functioning as data of server and application program also other equipments. Topology of LAN usually is network star and bus of network.

LAN can be attributed to other network outside organization, so that LAN can change over information with other network. For this, hence LAN require a gateway the in the form of communication processor. A gateway will connect LAN with other network though differ protocol. If some is same networks will be connected, hence required a bridge. If LAN will be attributed to other LAN or with WAN, hence required a router.

Network of LAN require special operating system is so-called with Network Operating System ( NOS ). Some Network Operating System the famousness for LAN is Novell Netware, MS Windows NT Server and IBM’s  OS / 2 Warp Server.

In process development of him, network system developed to become Wide Area Network system. Wide Network System is a connective system of computer resources separate far one another. Because connecting in area which is far separate, wide network using many medias of satellite and microwave

There is two kinds of wide network system, that is  :

1.      Wide Area Network. 

2.      Value Added Network.

1.      Network system in the form of  Wide Area Network.

Wide Area Network is computer network wich entangle some node the separateness far and attributed to link. Link is communications path which weared many by WAN by using special phonecall paths.

 

2. Network system in the form of  Value Added Network.

Value Added Network is a made by computer network a service firm of commercial network which equiped by many additional facilities.

B.  Network Topology

B.1. Star Network.

Star Network is a network system attributing to a node center and form like star. All communicationses handled and arranged direct by node central. Node central do all responsibilities to arrange information current among other node. If node which is one wishing to communicate with the other node, hence have to pass node central. Node central usually in the form of big computer which attributed to other node which in the form of some terminals pass a link.

B.2. Bus Network.

Bus Network is a connective network some node in data paths. each node can do different operation duty. In bus of network there no node central and all node have same statuses, except a node which earn to be determined as server.

B.3. Loop Network.

Loop Network is a coresponding network between node serially in the form of a closed cirche. In the form of this there no node central, altogether have  same statuses, except one of the node determined as server.

B.4. Ring Network.

Ring Network is aliance form network loop and bus of network. If one of the node not function, hence will not influence communications of node other because separated from data path.

B.5. Hierarchical Tree Network

Hierarchical Tree Network is this network form is like tree branching, what consist of center of node attributed to other node by have ladder.

 B.6. Web Network.

Web Network is network form which is each node in network can relate to the other node passlink. Web Network used if wanted all node can correlate one another him.

B.7. Meta Network.

Meta Network is aliance from some networks which forming one system.

 

H. SYAMSUDDIN, S.Pd, M.M

Guru TIK & Ka.Lab.Komp