Networking Concepts

Networking of computers mean interconnection of two or more computers or computer peripherals, which are joined by some type of communication media.

Advantages Of networking

• Sharing of data – Computers if networked, can share data amongst themselves.
• Sharing of peripherals – Computers can also share expensive peripherals like printers, scanners, etc.
• High communication speed– Sometimes inter office mail takes long time for receipts, but in case of a computer, the communication speed is very high and data reaches the destination quickly.
• High communication accuracy – Data transmitted does not get lost and no ambiguous messages are taken by the message from others. Messages are more easily composed, edited and saved for future use.
• Interactive data transfer – Data can be transmitted in interactive format, for which various media (sound, animation, video, etc.) are used.
• Lower cost – Data transmission being fast and accurate is cheaper than a fax.

There are different types of networks. They are classified according to the geographical area they can cover, as

LAN (Local Area Network)

This type of network can transmit data within a local or small area, usually one kilometer across like within an office, within a floor of a building, amongst various floors of a building, etc. As they cover smaller distances hence wired media – cables is used as an interconnecting medium between computers.

Advantages of LAN

• Data transmission speed is high, in the range of 10 or 100 Mbps.
• Low errors are encountered during data transmission.
• LAN increases productivity of employees, of an office.

Disadvantages of LAN

• LAN setup and maintenance require high cost.
• Experts are required for proper maintenance of a LAN.
• As data is shared, proper security measures are required for proper functioning of a LAN.
• All application software does not run over a network.

WAN (Wide Area Network)

This type of network can transmit data over large geographical areas. It interconnects long distances. It can also interconnect various LAN in different locations, as a single network, spanning large distances. For example Internet is a WAN.

Advantages of WAN

• It interconnects distant places, which is not possible by LAN.
• It serves various users in different locations.
• Cost of communication over long distances is very low.

Disadvantages of WAN

• WAN setup and maintenance require higher cost.
• Data transmission speed is lower than LAN.
• High errors are encountered during data transmission than that in LAN.

Topology

Topology means the manner in which various physical devices are connected in a network. Some topologies are

Bus

In it a single main cable runs across the network and it is connected to each node (computer or device) by another cable joining it and the computer. Thus, computers access the network from end to end.

Ring

It is similar to bus, but in it nodes are connected to each other in a circle with cable segments.

Star

Each node is connected to a central node by a dedicated cable between it and the central node.

Internet

It is an example of WAN (Wide Area Network). It is a very huge network and is also known as worldwide network of networks. It has a backbone network operating at high speed. Internet works on TCP/IP (Transmission Control Protocol / Internet Protocol). A protocol is a set of rules and regulations, about how data should be transmitted over a network. Internet provides various services like E-mail, WWW, FTP, etc. Internet can be accessed by an ISP (Internet Service Provider) like BSNL, MTNL, Satyam, Airtel, etc. in India.

Intranet

It is WAN which uses Internet for transmission of data. It interconnects various offices of a company, which are at distant places. Different offices are interconnected and they interact, as if they are on a LAN.