Computer Networks
Classification of computer network is divided into:

    Based on geography, computer network divided into local areas network or Local Area Network (LAN), metropolitan area networks or Metropolitan Area Network (MAN) and wide area network or wide area network (WAN). [7] [8] local area network ]] is a private network inside a building or place that size up some 1-10 kilometers. [7] [3] LAN is often used to connect personal computers and workstations (workstations) in a corporate office or factories to use shared resources (eg printers (printers) and exchange information. [3] While the metropolitan area network is a LAN network expansion to include a fairly broad one, consisting of dozens of buildings within 10-50 kilometers. [8] [7 ] used transmission cable is fiber optic cables (Fiber Optic). [8] wide area network is a network of intercity, inter-provincial, inter-state, even between continents. [8] The distance could cover the whole world, for example, a network that connects all the banks in Indonesia, or the network that connects all Indonesian representative offices around the world. [8] The main transmission medium is the communication via satellite, but many rely on fiber-optic connections between countries. [8]
    Based on the function, divided into client-server network (client-server) and End to end Network (Peer-to-peer). [8] Network client-server on one computer ddasaranya prepared to servers (server) from other computer as a client (client). [8] All service requests from the client computer resource should be passed to computer servers, computer servers that will manage the service. [8] If communication is very busy service requests could even put up more than one computer to servers, so no division of tasks, such as file-server, print-server, database server, and so on. [8] Of course, the configuration of computer servers usually more than the client computer configuration both in terms of memory capacity, capacity of hard disk {disk), and the speed of prosessornya. [ 8] The end to end network is indicated with computers to support each other, so that each computer can request the use of shared resources from other computers, so too must be ready to serve requests from other computers. [8] The network model is usually only applied to the number computer that is not too much, maximum 25, because communication will be complicated and bogged down when the computer too much. [8]
    Based on the network topology, computer networks can be distinguished [3]:
        Bus topology
        Star Topology
        Ring Topology
        Mesh topology
        Topology trees
        Linear topology
    Based on the distribution of sources of information / data
        Centralized network

            This network consists of client computers and servers in which a client computer that serves as an intermediary to access sources of information / data from one computer servers. [9]

        Distributed Network

            Is a combination of several centralized network so that there are several computer servers that are interconnected with the client establish a certain network system. [9]

    Based on the data transmission medium
        Wired Network (Wired Network)


            In this network, to connect one computer to another computer in the form of a network cable connecting required. [9] The cable network is working on sending information in the form of electrical signals between networked computers. [9]

        Wireless network (Wi-Fi)

            Is a network of the medium in the form of electromagnetic waves. [9] In this network cables are not required to connect between computers because it uses electromagnetic waves will transmit signal information between networked computers.