Page 2 - LN1

Lesson Note

• The IP (i.e., Internet Protocol) part is responsible for handling the address of destination
computer so that each packet is routed (sent) to its proper destination. You shall learn about
TCP/IP in details later in the chapter.

Steps followed for communication is Internet are:
• At the source computer, the message or the file/document to be sent to another computer is
firstly divided into very small parts called Packets.
• Each packet is given a number serialwisee.g., 1, 2, 3.
• All these packets are then sent to the address of destination computer.
• The destination computer receives the packets in random manner. (It may even receive packet
10 before packet 1 arrives). If a packet is garbled or lost, it is demanded again.
• The packets are reassembled in the order of their number, receiver system acknowledges and
the original message/ file/ document is obtained.

INTERSPACE
The future of Internet is said to be in Interspace. Let us know what Interspace is.
InterSpace is a client server software program that allows multiple users to communicate online with
real time audio, video and text chat in dynamic 3D environments. InterSpace provides the most
advanced form of communication available on Internet today.

Terminologies of a Network
Node/Workstation – Any computer attached to a network is a node of the network and are seeking to
share the resources of the network.
Server – A computer in a network that facilitates the sharing of data, software and hardware resources
to other computers in the network. Server can be
• Dedicated server (can be file/printer/modem server etc)
• Non-dedicated server
NIU (Network Interface Unit)/ NIC (Network Interface Card) – A NIU is a device that helps to establish
communication between the server and the workstations. It is attached to each workstations and
servers. Each NIU has a unique identification number (given by manufacturer), called MAC (Media
Access Control) address and helps to identify each node uniquely in a network.

Switching Techniques
In large networks there might be multiple paths linking sender and receiver. Information may be
switched as it travels through various communication channels. There are three typical switching
techniques available for digital traffic.

Circuit switching – In this technique first a physical connection is established between the sender and
receiver computers and then the data transmission starts. Example – Telephone network. The working
principle is to set the end-to-end connection and then to start the transmission.
Simple, but as dedicated channel needed so poor utilization of channel.

Message switching