INTERNET

1. 5 Chapter INTERNET

2. Objectives of this chapter: You can… Discuss the history of the Internet Explain how to access andconnect to the Internet Describe the types of Web sites Imagine the future of the internet

3. This chapter covers Introduction History Internet Software Internet Services Future of the Internet Overview GO!

4. 5.1 Introduction

5. What is the Internet? The largest network of networks in the world Uses TCP/IP protocols and packet switching Runs on any communications substrate Introduction

6. Also called the Net One huge global interconnected networks that comprised millions of computers A world-wide collection of networks that links millions of businesses, government agencies, educational institutions, and individual Internet services widely use – World Wide Web & e-mail Introduction (cont’d)

7. A technology to link LAN network to a bigger network Every computer in the network can directly share data and information with other computers Internet Service Provider (ISP) are responsible to provide Internet services: Examples: Jaring, MIMOS, TMNet, Telekom, Maxis.net , Time Telekom Introduction (cont’d)

8. “Galactic” Network A network that is connected globally where each computers are able to retrieve data directly and share information Every computer on the internet has an IP address (similar to a telephone number) and it is able to exchange data directly with other computers by “dialing” the computer’s address The Internet uses packet switching concept where data sent are divided into smaller units known as packets Each unit of packet has a number and destination address Introduction (cont’d)

9. Interoperability The Internet allows every computer in a network to operate even tough each remote computers are of different brands and models or in a cross-platform network. For example, a user can contact other computers like MAC, Windors PC, UNIX Machine and Mainframe using MAC. Telnet is an example of an Internet service where a user can access a remote computer in a network after keying in login and password Introduction (cont’d)

10. How to connect to the Internet? Introduction (cont’d) Slow-speed technology High-speed connection Dial-up accessmodem in your computer uses a standard telephone line to connect to the Internet Digital subscriber line (DSL),cable telephone Internet services (CATV), cable modem,fixed wireless, and satellite modems Connection must be established each time you log on. Slow but inexpensive Connection is always on—whenever the computer is running

11. All computers have a unique Internet Protocol (IP) address. All computers use TCP/IP protocol to communicate. Requires communication device like modem, ISDN adapter, Ethernet card, telephone line Download - to transmit data from a remote computer to a local computer Upload - to transmit data from a local computer to a remote computer Introduction (cont’d)

12. TCP/IP Transmission Control Protocol/Internet Protocol (TCP/IP) – a combined set of protocols that tells computers how to exchange information over the Internet. TCP monitors and ensures correct transfer of data. IP receives the data from TCP, breaks it up into packets, and ships it off to a network within the Internet. Introduction (cont’d)

13. Each Internet services require different protocols. Examples like FTP and HTTP sit on top of TCP/IP. FTP (File Transfer Protocol) – accessed using FTP browser or DOS prompt HTTP (Hypertext Transfer Protocol) – accessed using Web Browser POP3 and SMTP – accessed using Mail Browser Introduction (cont’d)

14. Role of ISP Access is provided by the Internet Service Provider (ISP) i.e. Jaring, TMNet. ISP provides a back bone to the network – either: PSTN (Public Switch Telephone Network) ISDN (Integrated Services Digital Network) or SONET (Synchronized Optical Network) ISP also provide domain name registration for each organization. Introduction (cont’d)

15. What is a domain name? Introduction (cont’d) • Text version ofInternet protocol (IP) address • Number that uniquely identifies each computer or device connected to Internet

16. Communication Link Shell Access Usually by free shell account providers used for text-based email, IRC. Modem and phone line  temporary IP Computer  providers that connect to the Internet (not directly connect to Internet) Dial-up Point-to-Point (PPP) Modem, phone line, ISDN adapter  temporary IP Computer  Internet Introduction (cont’d)

17. Cable/Satellites Dial-up with modem and phone line  temporary IP. Faster transmission rate. Leased Line Modem and dedicated line  fixed IP. Usually to host Internet/Web Server. Support Extranet (external Internet) i.e. Sony Malaysia and Sony Japan. Introduction (cont’d)

18. How might data travel the Internet using a cable modem connection? How the Internet Works

19. 5.2 History

20. 1962 Started from Lickder’s “Galactic Network” idea that introduced the concept of Packet Switching. RAND researchers concluded that Packet Switching was the best concept 1968 Lawrence G Roberts from DARPA formulated the specifications for Advanced Research Agency Network (ARPANET) 1969 ARPANET connected 4 computers in California and Utah, connecting university and research center with the Department of Defence (DoD) - USA History

21. 1973 ARPANET became an international network 1981 ARPANET connected 213 computers 1984 Total computers connected to ARPANET reached 1000 1987 Total computers connected to ARPANET reached 10,000 History (cont’d)

22. Packet Switching In 1962, Galactic Network introduced the concept of packet-switching, a new technology to transfer information between 2 distant computers Packet-switching technology will break each message/data into smaller unit called packets for speedy and guaranteed delivery Each packet carries a unique identification number and the destination address History (cont’d)

23. ARPANET – (Advanced Research Projects Agency Network) In 1968, L.G. Roberts from DARPA institute published a specification for Advanced Research Agency Network (ARPANET) In 1969, ARPANET successfully connected 4 research computers in California & Utah E-mail services was introduced in 1972 – people exchange text messages across a long distance In 1973, ARPANET become international network History (cont’d)

24. By 1981, ARPANET has 213 inter-connected computers called the Internet In 1982, ARPANET was taken by DARPA and given to NSF (National Science Foundation) In 1983, the Internet Protocol (TCP/IP) was introduced by Kahn & Cerf By 1984 the network has grown to 1,000 computers and increased to 10,000 in the following 3 years History (cont’d)

25. World Wide Web (WWW) In 1989, a researcher named Tim Berners-Lee proposed the idea WWW while working at CERN (a physics laboratory in Europe) In 1993, a group of professors and students at the University of Illinois National Center for Supercomputing Applications (NCSA) release mosaic – the first graphically based web browser History (cont’d)

26. A worldwide collection of electronic documents Also called the Web Each electronic document is called a Web page Can contain text, graphics, sound, video, and built-in connections A Web site is a collection of related Web pages History (cont’d) • What is the World Wide Web (WWW)?

27. 5.3 Internet Software

28. Internet software allows user to use the services provided by the Internet 1. Web Browser Allows user to view web page and browse Internet sites Internet Software

29. Example of Web browser MicrosoftInternetExplorer Netscape Mozilla Firefox Opera Safari Internet Software - www

30. How does a Web browser display a home page? Step 2.Web browser looks up the home page setting Step 4.The home page displays in the Web browser Internet Software - www Step 3.The Web browser communicates with the ISP’s server to retrieve the IP address. The IP address is sent to your computer. Step 1.Click the Web browser program name

31. 2. Pager A software that allows a individual user to communicate with other Internet users. Each user has to have the same software in their computer and register at a certain website for them to obtain an unique identity or ID The user can then use this software by adding in other user’s ID in his/her pager software to be able to know whether the other user is online on the Internet Internet Software (cont’d)

32. It is usually used to communicate with other “known” individual; as the user needs to know the other user’s ID Examples of pager software - Yahoo Messenger, ICQ and MSN Messenger etc Some software such as Skype also allows user to communicate via telephone, using Internet as the intermediary medium Internet Software (cont’d)

33. 3. E-Mail A software that allows user to read, write and store e-mails Examples of e-mail software – Microsoft Outlook, Outlook Express, Netscape Messenger and Mozilla Thunderbird 4. Internet Relay Chat (IRC) A software that allows user to use Internet Relay Chat services (Real-time Chat). An examples of IRC software – mIRC Internet Software (cont’d)

34. 5. Download Manager Allow users to download files to their computers It can continue to download the file if the user decide to continue downloading at a later time, or if the user got disconnected and connected again from the network, without having to start the download again from the beginning of the file However, to continue downloading from where you stop depends on the server that hosts the file(s). Note that not all server support this process The software is also capable of searching other server that hosts the same file(s), which is faster and/or closer to the user’s location. E.g. – FlashGet, Download Accelerator Plus, Godzilla and RealNetwork download manager Internet Software (cont’d)

35. 6. Internet Music Player Capable of playing music from the internet Some web pages like radio or tv station’s web sites, provide a web based audio and/or video broadcasting/streaming through the internet. It can only be viewed using special software Among the popular software are RealPlayer and Microsoft Media Player This technology of listening/viewing audio/video through the internet is called “Streaming” Internet Software (cont’d)

36. 5.4 Internet Services

37. 1. E-mail Used to send messages digitally through the internet Every message delivery should have: address of the recipient, address of the sender, subject of the message and body of the message Email operations include - reply, forward, delete, save and print Email will take a few seconds to be sent, it will be stored in the recipient’s email server until the recipient retrieves it. Then the recipient may reply, forward, delete, save or print the email Internet Services

38. azuramasura@jpa.gov.my User name/ID: azuramasura Domain name: jpa Top-level domain: .gov Two-letter country extension: .my Internet Services (cont’d)

39. How does an e-mail message travel? Step 1.Using e-mail software, you create and send message Step 2.Your software contacts software on your ISP’s outgoing mail server Step 4.When recipient uses e-mail software to check for e-mail messages, the message transfers from incoming mail server to recipient’s computer Step 3.Software on outgoing mail server determines best route for data and sends message, which travels along Internet routers to recipient’s incoming mail server Other Internet Services

40. 2. File Transfer Protocol (FTP) FTP is a protocol used to transfer (download or upload) files between computers on the internet. FTP Client software can be used on PCs to connect to FTP server. 2 types of modes to transfer files using FTP are: ACII (text files) Binary (usually programs, graphics and basically all other file types other than text) Internet Services (cont’d)

41. Usually username and password is required to login to FTP service on a FTP server Anonymous FTP is one way to connect to FTP server without having to identify yourself. Anonymous FTP example: Type the following command on a DOS prompt  ftp ftp.jaring.my Enter the following username an password when asked Login: anonymous or Anonymous Passwd: <enter your email address> Internet Services (cont’d)

42. 3. Newsgroup/Message boards Internet Services (cont’d) • Newsgroup • Online area where users discuss a particular subject • Message board • Type of discussion group • Many Web sites use message boards because they are easier to use

43. 4. Chat Real-time typed conversation that takes place on a computer Chat room is location on server that permits users to discuss topics of interest Instant Messaging Example: mIRC, Yahoo Messanger, Skype, MSN Messanger etc Internet Services (cont’d)

44. 5. Internet Telephony Real-time audio and video technology, such as Voice Over IP (VoIP) and Video Conferencing is getting more popular VoIP techology uses three methods: PC-to-PC – Using sound card, microphone and computer Phone-to-PC Phone-to-Phone – Using Telephones that support VoIP The quality is not guaranteed (No QoS), There are noise and echo. All calls are charged as local calls.

45. 6. Telnet Allows users to login to remote computers using valid username and password. Users need to have an account on the remote computer. Issue the following command in DOS promt telnet www.upm.edu.my A secured alternative to telnet is by connecting to remote computer using SSH (Secure Shell) ssh www.upm.edu.my The remote computer must have Telnet/SSH server running for users to connect to it Internet Services (cont’d)

46. 7. Ping Allows users to check whether a remote computer is up/operational. Type the following command in DOS prompt ping www.upm.edu.my This command or service might not work properly if: The server or user is behind a firewall and it blocks ICMP request. Your ISP does not allow this type of request. The server has an embedded firewall on it and it blocks ICMP request. Internet Services (cont’d)

47. 8. Web Sites A framework architecture used to share and access documents that is connected to the internet Information displayed are intuitive, easy to use and using interesting graphical interface Information are exchanged using client server concept. A web document that interconnects pages is called hypertext A text string that links a page to other pages is called a hyperlink Hypertext that contains other media (graphics, audio, video, etc.) is called hypermedia WWW is a world wide hypermedia and hypertext system Internet Services (cont’d)

48. Every address is unique and is called Universal Resource Locator (URL) http://www.jaring.my/intro/index.html URLs consists of 4 parts: Protocol: HyperText Transfer Protocol (HTTP) Server: Internet domain name Path: The location of the document in the server- folder/directory name Resources name: The filename, usually in one of these formats html/cgi/sound/movie/graphic server path File name protocol Internet Services (cont’d)-website

49. What is Search engine Internet Services (cont’d)-website • Program used to find Web sites and Web pages by entering words or phrases called search text • Also called a keyword

50. What is a hit? Step 2.Select type of search you wantto run Step 1.Go to search engine Step 3.View hits Step 4.Click link to view Web site Internet Services (cont’d)-website • Any Web site name that is listed as the result of a search