the internet

The Internet

Chapter VI?

The Internet is a worldwide collection of interconnected networks.

Just how big the internet?

The Net, the internet’s nickname, links over a million networks with even more internet host server computers in every country in the world.

What is the Internet?

Some Historical Perspective of the Internet

A small group of computer scientist on both coasts of the United States were busy creating a national network that would enable the scientific community to share ideas over communication links.

The Department of Defense’s Advance Research Project Agency (ARPA) sponsored the project, named, ARPANET, to unite a community of geographically dispersed scientists by technology.

The first official demonstration linked UCLA with the Stanford University, both in California but, this historic event had no records ,photographs and reports.

By 1971, the ARPANET included more than 20 sites including Harvard.

By 1981, the ARPANET linked 200 sites.

ARPANET eventually lost its reason to exist as other special-interest networks took its place.

In 1990, ARPANET was eliminated, leaving behind a legacy of networks that evolved into the internet.

The Transmission Control Protocol / Internet Protocol (TCP/IP) are the communications protocol that permits data transmission over the internet.

Communications over the Net are built around this two-layered protocol.

Protocol is a set of rules computers use to talk to each other.

The Transmission Control Protocol (TCP) sets the rules for the packaging of information into packets.

The Internet Protocol (IP) handles the address, such that each packet is routed to its proper destination.

♣ The Uniform Resource Locator (URL) is the internet equivalent of an address.

♣ It gives those who make information available over the internet a standard way to designate where internet elements, such as server sites, documents, files, newsgroups, and so on can be found.

Ex. http://www.rtu.edu.ph/rtu.php?cid=7/Careers6.html

URL: The Internet Address

http://www.rtu.edu.ph/rtu.php?cid=7/Careers6.html

specifies access method.

This indicator tells your client software to expect an http (hyperText Transport Protocol) file.

http is the primary access method for interacting the internet.

Access Method

http://www.rtu.edu.ph/rtu.php?cid=7/Careers6.html

Domain Name

The Domain Name, which is a unique name that identifies an internet host site, will always have at least two parts, separated by dots (periods).

The part to the right of the domain name is the most general and the part on the left is the most specific.

Domain Name

Domain Description

com Commercial Organizations

edu Educational Organizations

gov Government Organizations

mil Military Organizations

net Network service providers or network resources

org Non-profit organizations

Common country codes

Domain Description

au Australia

dk Denmark

fr France

jp Japan

Major Domain Name Types

http://www.rtu.edu.ph/rtu.php?cid=7/Careers6.html Directoryo The Directory contains the resources for a particular topic.

Filenamehttp://www.rtu.edu.ph/rtu.php?cid=7/Careers6.html

Filename

o The specific filename of the file that is retrieved from the server and sent to your pc over the internet.

Directory

oThe HTML (Hypertext Markup Language) is the language used to compose and format most you see when cruising the net.

Browsing is when browsers poke around the internet with no particular destination in mind.

A ll the popular portals on the Net offer a menu tree of categories, these includes Yahoo, Facebook, Multiply, Google and others

Browsing the Net

• An internal portals is always a good place to start. These portal sites divide the wealth of resources on the internet into about a dozen major categories (for ex. Arts, business, computers, education, entertainment, health and so on)

• You may navigate through several levels of categories before reaching the pages you want.

• Many pages have banner ads that entice us to click on them and travel to totally unrelated site.

Search engine

Search Engine provides a resource discovery tool to help you to find the information or service you need.

The rules by which you enter the keywords and phrases vary slightly between the search engines.

Using Search Engine to Search the Net

Searching

Tips

Read the search rules.

If you don’t get the results with one search engine, try another.

The results of the search are seldom exhausted .

Choose search words carefully.

Be persistent.

WWW: World Wide Web World Wide Web affectionately called the Web, is an

internet system that permits linking of multimedia documents among servers on the internet

By establishing a linked relationship between Web documents, related information becomes easily accessible

These linked relationships are completely independent of physical location.

Internet Applications: The Web, FTP and More

Attributes set Web servers apart from other internet servers

User-friendly

Multimedia Documents

Hyperlinks

Interactive

Frames

The File Transfer Protocol (FTP) allows you to download and upload files on the internet.

FTPing is a popular activity on the net.

You can download exciting games, colorful art, music from up and coming artists and applications programs basically anything that can be stored digitally.

Many FTP sites invite users to contribute (upload) files of their own.

FTP: Downloads for the asking

Gopherspace is the home of thousands of gopher servers throughout the world.

The Gopher system, which predates the World Wide Web, was developed at the University of Minnesota.

It is designed for distributing, searching, and retrieving documents over the Internet

Gopherspace: Go-for Information

Gopherspace was released by Mark McCahill, together with his associates Farhad Anklesaria, Paul Lindner, Daniel Torrey, and Bob Alberti

Telnet:

Remote Login

Telnet refers to a class of internet application programs that lets you log onto a remote computer using the Telnet communication protocol.

Telnet is a terminal emulation protocol that allows you to work from a PC as if it were a terminal linked directly to a host computer.

Once online to one of these sites, you can run a normal interactive session as if you were sitting at an on-site terminal.

TELNET : REMOTE

LOGIN

hi hello Communicating with People: E-mail,

Newsgroupand Chat

Electronic mail, most commonly referred to as email or e-mail since 1993,

is a method of exchanging digital messages from an author to one or more recipients. Modern email operates across the Internet or other computer networks.

E-mail sent to a particular person can be “opened” and read by that person.

E-mail on the

Net

The attached file is routed to the recipient’s e-mail server computer along with the server.

A news group is the cyberspace version of a bulletin board.

USENET is a worldwide network of servers that can be accessed over the internet.

“Newsgroups” is misnomer in that you seldom find any real news , they are mostly electronic discussion groups.

Newsgroup : Electronic Bulletin Boards

Newsgroups

The Internet Relay Chat (IRC) protocol allows user to join and participate in group chat sessions.

A chat session is when two or more internet users carry on a typed, real-time, online conversation.

Chatting is a favorite past time of millions of cybernauts.

INTERNET RELAY CHAT: CHIT-CHAT

INTERNET RELAY CHAT

E-commerce is simply conducting business online and that , of course, means the electronic transfer of money of plenty of opportunity for fraud and theft.

Issues on the Net

Firewall is software that is designed to restrict access to an organizations network or its intranet. The firewalls screens electronic traffic in both directions so that organizational security is maintained.

Spam is unsolicited junk e-mail , mostly advertising for commercial products or services.

Spammers or those who send spam unsuspecting people with political messages.