Networks

A Computer Network can be defined as a group of computers and other peripheral devices that are linked together for the purpose of sharing data and hardware resources.

Transmission medium is the physical path through which the message travels from the sender to the receiver. Twisted pair cable, coaxial cable, fibre optic cable and radio waves are some examples of transmission medium.

Two advantages of networking are:

1. Reduction in hardware costs — In a network, the hardware devices that are not used very often, like modems, printers, scanners, CD-writers, etc. can be shared. This reduces the cost of the hardware.
2. Efficiency — In a network, the deletion, modification or upgradation of the software/data is to be done at a single point only. This brings more efficiency and effectiveness into the working system.

A Coaxial cable consists of central copper wire surrounded by insulation and then a shield of braided wire. It is used in transmission of video, communications and audio specially in the cable television industry.

Difference between Broadband and Baseband Coaxial cable is that Baseband Coaxial cable supports quick transmission of a single signal at a time and is mainly used for LANs whereas Broadband Coaxial cable transmits multiple signals at the same time and is used for longer distances.

Domain name is a unique name given to each website or resource connected to the internet. Domain names are easier to remember than IP addresses since name has strong correlation with the website. For example, to use Google search engine, the domain name is google.co.in and to use Wikipedia, it is wikipedia.org.

A Gateway is a network point that acts as an entrance to another network using different protocols. It is a shared connection between a local area network and a larger system i.e. WAN. It basically works as the messenger agent that takes data from one system, interprets it and transfers it to another system.

Wi-Fi

Wi-Fi stands for Wireless Fidelity. It uses radio waves to create a secure, reliable and fast Wireless Local Area Network (WLAN). The devices require a wireless adapter to connect to the WLAN using WiFi. It is widely used to share an internet connection among the devices connected to the WLAN. Its advantages are:

1. It can be used to connect to Internet anywhere and anytime and is quickly replacing the wired medium.
2. It is relatively cheaper compared to the wired medium.
3. Multiple devices can be connect with WiFi to create a WLAN.

Its limitations are:

1. Higher power consumption.
2. Slower speeds than wired medium.
3. Transmission breaks or slows down when there is noise interference.

Modem

Modem stands for Modulation/Demodulation. Modulation is the process of converting digital signals to analog and Demodulation is the process of converting analog signals to digital i.e. reverse of Modulation. Thus, Modem helps in transmitting and receiving data between devices over a transmission medium like telephone lines, co-axial cables, radio waves, etc. Modem are of two types — internal or built-in modems and external modems.

Cluster Area Network

Cluster Area Network (CAN) also known as Campus Area Network, is a network comprising a series of small LANs over a small geographical area, such as a college campus, office building, etc. It is generally limited to an area between local area network and metropolitan area network.

Riya can connect her mobile and computer through Bluetooth wireless networking technology. As the mobile phone can be brought in close range to the computer so the transmission range of Bluetooth is well suited for this setup.

As the branches are located in two different cities so Mr. Nanda should use Wide Area Network (WAN) to connect the computers of the two branches.

To connect the computers present in different buildings of the school, a Cluster Area Network (CAN) is best suited.