Computer Science XII

Components of Computer Network

The communication between two computers is possible by interacting between hardware and software Components.
1). Hardware Components:
All the physical component of network that is used to connect or communicate is hardware components. The different hardware components are:

• Server:
A server is a computer that makes its resources available to the network and responds to the commands of a client. The server in a network performs a variety of complex tasks. It is the main computer in network which has high storage capacity and high processing speed. The following are some examples of different types of server included on many large networks:

i). File and Print Servers
ii). Database Servers
iii). Mail Server

• Client / Workstation:
A client is a computer that uses the resources made available by a server. The client must have sufficient processing power on its own to run applications that interact with the resources on the server. It is also called as work station

• Cables:
Cables are the pathway or channel along which the signals or data can be transmitted from one point to another. The most commonly used cables are coaxial, twisted pair and fiber optics.

• Network Interface Card:
Network Interface Card is the computer circuit board or card that is installed in a computer so that it can be connected to a network by using physical channel. Each NIC is assigned a unique MAC (Media Access Control) address by the manufacturer through which data is sent to the destination. The main function of NIC is to convert data into electrical signals and transfer them through cable and vice versa.

• Hub:
Hubs are centrally connectivity devices that connect computers in a star topology. Hub contains multiple ports for connecting to network components. It amplifies (/increase) the signals and sends them to all connected devices. Use of hub has become very common in most of the computer networking as it cost lower and easier to install.

• Connectors:
It is an interface between NIC of the computer and the cable that passes data from one computer to another. It depends on type of cable and devices used in the network. The different types of connectors are; BNC connector, RJ 45, ST, RJ 12 etc.

• Repeater:
A repeater is a physical layer device used to interconnect the media segments of an extended network. It amplifies the incoming signals, creates a new copy of it and transmits the signals on the network. A repeater essentially enables a series of cable segment to be treated as a single cable.

• Bridge:
A bridge is a device that passes data packets between multiple network segments that use the same communication protocol. A bridge passes one signal at a time. It filters the data or inspects incoming signals and decides whether to forward the signals or discard them.

• Switch:
Switches are similar to bridge but offer a more direct network connection between the source and destination computers. The main difference between bridge and switch is the way that filtering happens. With a switc0h, filtering and performance better than bridge.

• Router:
Router is a device that acts like a bridge or switch but provides more functionality. It uses addresses for filtering and forwarding the data. Router enable all user in a network to share a single connection to the Internet or a WAN.

• Gateway:
A gateway is a device that enables communication between different network architecture. A gateway takes the data from one network and repackages it, so that each network can understand the other network’s data.

• Modem: (Modulation-Demodulation)
A modem is a communication device that enables a computer to transmit information over a standard telephone line. A modem is required when connecting to the Internet using telephone line. It is an essential link between the computer running browser and dial up service providers. A modem is needed to convert digital signal to analog signal and vice versa. During the modulation phase, it is used to translate digital signals of a computer to analog signals, which are then transmit across the standard telephone line. The reverse takes place during its demodulation phase, as the MODEM receives analog signals from a phone line and converts them into digital signals for the computer. A modem speed is measured in terms of BPS (Bit Per Second). Speed of telephone service also affects the connection speed. ISDN (Integrated Service Digital Network) allows a modem to connect at 128 KBPS.

Analog Signal:
An analog signal is a constantly changing electrical wave signal that changes in a rounded or smooth pattern.

Digital Signal:
A digital signal uses a square waveform, which is reliably used to transmit electronic data.

Types of Network (Prev Lesson)
(Next Lesson) Transmission Media or Communication Media or Network Media
Back to Computer Science XII

No Comments

Post a Reply

error: Content is protected !!