COURSE NOTICE FOR CLASS X
1.INTRODUCTION TO INTERENET AND ITS SERVICES
Internet : It is a network of tens of thousands of computer networks. Every network and every network on these networks exchange
Information accounting to certain rules called protocols. Two protocols used for working with the Internet are Internet Protocol or IP and
Transmission control protocol or TCP, generally known as TCP/IP. It enables the computer to talk the net’s language. It needs to known
your IP address and the address of the server to convert domain names into IP address and connects you. All your net softwares such as
newsreaders, web browsers and mail clients rely on to converse.
2. PROTOCOLS OF INTERNET
- Internet Protocol (IP): The most important protocol on which the internet is based. It defines how packets of data get from source to
destination. The path of each packet is determined in a dynamic manner. IP helps to find how a packet received at an intermediate nods will
be transmitted so that it reaches the correct destination.
- Transmission Control Protocol (TCP): The internet is based on the principle of packet switching for data transmission. At TCP level bytes
are organized into packet. At the destination, the packets are reorganized into files as they existed in the source computer. Each packet is stamped
with the IP addresses of the source and destination computer.
- File Transfer Protocol (FTP) : It is used to move files from one computer to another irrespective of the geographical location. It works in
collaboration with IP to guarantee that data is correctly transmitted by the source computer and received by the destination computer.
- Hyper Text Transfer Protocol (HTTP) : It is a protocol to transfer hypertext pages across the world wide web.
- Point to Point Protocol (PPP) : All computers connected to internet have a unique address. Every time your computer is connected to the
internet through modem, it is given a temporary IP address using PPP. It does not have permanent address. However computers permanently
connected to the internet have permanent IP address.
3. ADDRESSING IN INTERNET
- IP Addresses : Every computer connected to the internet has an unique IP address (written in dotted numerical notation) which corresponds
to its domain name. Domain name services convert one to the other for e.g 184.108.40.206. Since it is easier to remember a name than a number,
the internet uses Domain Name System (DNS) parallet to the IP number system. The Domain Name Services locate the numerical IP address
corresponding to the host name.
- Domain : Part of the DNS that specifies details about the host, such as its location and whether it is part of a commercial, government or educational
entity. For e.g. all internet email addresses are in the formet user@host .The host portion breaks down further into
c) Country code
here → shesldh is the user name
net is the domain type
List of Domain Types
a) com : Company or commercial organization
b) edu : Educational Institution
c) gov : Government body
d) mil : Military site
e) net : Internet Gateway or ISP
f) org : Non-Profit organization
Country Codes : Every country has its own distinet code although its not always used. If address doesn’t specify a code, it is more than likely, but not
necessarily, in the USA.
a) au : Australia
b) in : India
c) uk : United Kingdom
d) us : United States of America
e) ca : Canada
f) fr : France
The DNS address of computers in the internet have following from :
Type : // address
Where type is the type of the server
Address is the address of the server.
http : // www.discovery.com
here → http defines the type of the server and the protocol it follows.
→ www.discovery.com is the address of the server (web server) or domain name
4. TERMS RELATED TO WWW :
- Web Service: It is a place where information resides in pages. It is a programme that respond requests from web browsers to retrieve information.
- Web Sites : A web site is simply a collection of information in the form of files that is des to be accessed in a special way.