When you need to establish a computer network. You first need to do is to use some hardware devices connect each computer, these hardware devices in addition to the media, and also need to have the media connector, network interface board, Lee demodulator such as these lead is responsible for connecting the computer, the router works provided by this channel of data communication. Sometimes in order to extend the distance of transmission and ease of wiring, the number is also used for network interconnection devices, such as repeaters, hubs, bridges, and so on.

Each transmission medium has one or more physical connectors in order to connect a variety of devices. For example, a thin coaxial cable typically use a t-connector (or t-joint) will the media and the computer's network interface Board connects. Twisted-pair cable you need a BJ-45 connector (commonly known as Crystal head) twisted-pair and connect computer network interface board. In addition, like DH-25 (RS-232) connector, DB-15 connectors, and so on.

1, network adapter

Network Technical Board is also known as the network card, which contains all of the computers or other physical and logical connections between the devices and the media. In General, the network adapter is installed on your computer, through a connector (such as t-connectors or RJ-45 connector) to connect to on the cable. A network adapter can provide one or more connector types, for example, you can either connect the t-connector, you can connect to RJ-45 connector. So that the card can be either connected to the coaxial cable, you can also connect with twisted-pair continued. As long as the computer that is connected to the Internet, no is a workstation or a server, are equipped with at least one network adapter.

2, modem

Many types of modem, can be divided into three types: frequency shift keying, phase shift keying and amplitude shift keying.

Large local area networks, typically the turn is made up of a variety of topologies and cable lines, we route the cables on the same workstation is divided into a group, website construction issues in the work of each group have the same network address (workstation address must not be the same), different groups by connecting devices, such as e bridge connections.