|
|
Basic Internet
fundamentals
CHAPTER #
1
History of
Internet
- Internet Vast network
of networks, that connects millions of people world wide.
- Formation formed in 1968,(During
the Cold War Era) when the Department of Defence (US) created ARPA(Adavanced
Research Projects Agency). The ARPANET(ARPA NETWORK) allowed the government
(US) and researchers to interact from any location on the network.
- In the 1980's The Department
of Defence assigned the ARPA to NSF (National Science Foundation).
It increased the suppercomputer to FIVE.The NSF Network(NSFnet) plus
thousands of other networks combined togather make up what is call
INTERNET.
How The Internet
works
- TCP/IP: Transmision
Protocols and Internet Protocols are softwares used to connect one
computer to the Internet. TCP/IP makes sure that the information is
tranfered quickly and reliably. It breaks information into small packets.
If any packet is lost due to some reason, TCP/IP make sure that that
packet will be resend. If connection between two computers are not
working, the Internet protocol recognizes it and bypass that route
and take some other route to the destination.
- IP address: Each
site in internet is identified by an address called IP address. This
is used by the TCP/IP to address the packets of information it sends.The
IP address consists of a series of four sets of numbers separated
by dots so the name doted squads.
- Eg. 304.102.65.15
Clients and
Serverson the internet
- A client is program on
the user's computer which sends a reqest for an information to another
computer on the internet in which anither program called server is
installed. The server process the request send by the client and send
the client the required files of info.
Conecting to
Internet
The four main things required
to accomplish and internet tasks
- A computer connected to
the Internet using TCP/IP.
- An IP address of the computer
which is authourised to use.
- A client program.
- And info such as address
of the internet site.
Direct
vs Indirect connections
|
Direct
connection
- The computer is
connected to the Internet as an individual node wlth a dedecated
line.
- can handle large
bandwidth.
- The speed of connection
depend on the type of lines used.
- T3 45 M bps
- T1 1.54M bps
- 56K 56 K bps
- Routers are used
to for LAN based Direct connections to connect to internet.
|
Dial-up
connection
- The computer is
simple terminal.
- A modem is used
to connect to the Internet using a standard telephone line.
So the speed of connection is limited by the speed of the modem.
Typical modem speeds are,
- 56K bps
- 33.6K bps
- 28.8K bps
- 14.4K bps may
not support streaming audio & video.
|
Internet
protocols
|
| HTTP |
To transfer Web pages
from the Web server to client |
HTTP server |
| FTP |
To transfer large amount
of data |
FTP server |
| SMTP |
To send E-mails |
SMTP server |
| POP |
To receive E-mail |
POP server |
| Telnet |
To conect a remote time
sharing computer. |
Telnet server |
| NNTP |
To trasfer usenet news
articles |
NNTP server |
| Gopher |
To retrieve Gopher resourses |
Gopher server |
|
Domain Name
system (DNS)
The Domain name system translates
the dotted squads (numerical IP address) to easily remeberable domain
names. www.microsoft.com server type company domain name domain
category
The business
of domain names
The Internet Network Information
Center (InterNIC), established in 1993 as a project to lead corparations
and National Science Foundation (NSF) is the clearing house for all domain
names.
The Uniform
Resource Locator
Now a days the web browsers
are not only a web client but it can be even an FTP or Gopher client.
The URL consists of four defferent parts , that when combined, completely
define a file or service anywhere on the Internet. These are
- Protocol
- Domain name
- Path
- File name
Eg
- Web page http://www.geocities/sur_42/index.htm
- FTP ftp://ftp.apple.com
- Gopher gopher://gopher.tc.umn.edu/
- No URLs for E-mail or
news.
The information posted are
best to my knoledge. |
