1 Internet Hiroshi Toyoizumi toyo@u-aizu.ac.jp toyo@aoni.waseda.ac.jp.

transcript

Internet

Hiroshi Toyoizumitoyo@u-aizu.ac.jp

toyo@aoni.waseda.ac.jp

Introduction of the Internet

• System of Internet• What can be done using

Internet• Merit of Internet• Technologies in the Internet

Protocol Routing

Stand Alone

• Computers are used to be standing alone.

Connect two machines

• Sharing the information between two machines. Copying files etc.

Local Area Network (LAN)

• Connecting machines.

The Internet

• Connecting LANs globally.

Company A

University B

Agency CLab. D

Provider E

domain

What’s the Internet: “nuts and bolts” view

• millions of connected computing devices: hosts, end-systems pc’s workstations, servers PDA’s phones, toasters

running network apps• communication links

fiber, copper, radio, satellite

• routers: forward packets (chunks) of data thru network

local ISP

companynetwork

regional ISP

router workstation

servermobile

Domain

• The name of organization connected to the internet.

waseda.jp Waseda University waseda.ac.jp ntt.co.jp NTT kantei.go.jp Japanese government

Structure of Domain Name

• Domain name is consisted by the name, attributes and nationality of organization.

http://www.internic.net/faqs/authoritative-dns.html What is waseda.ac.jp?

“waseda” is the name of organization, “ac” represents academia, and “jp” means japan.

Nationality ca:Canada 　 uk:United Kingdom 　 fr:France 　 au:Australia etc.

Attributes co:company 　 go:government 　 ne:internet provider

Name You can name it!

Address

• You need address to send a message to the computer on the receiver side. Use IP address or domain name. IP address

Handled by computers. 164.125.25.10 Consisted by network number and computer number.

Domain name tractable for human being computer ----- aoni.waseda.jp mail ----- toyo@aoni.waseda.jp URL ----- www.waseda.ac.jp

Example of address

Waseda

Fukushima government

waseda.ac.jp

ntt.co.jp

pref.fukushima.jp

ルータ

den.ntt.co.jp(210.173.163.201)

aoni.waseda.jp(202.225.207.18)

www.abc.pref.fukushima.jp

toyo@aoni.waseda.ac.jp

mail address

Domain name

Domain name address

address

What you can do using internet

• Browsing （ World Wide Web(WWW ））• E-mail• FTP: file transfer• telnet: remote login to other computers• BBS (electric bulletin board)• Chat• Multimedia player (Video, music ）

•System to make and look homepages.•Using hyper link.•Browsers

Netscape Navigator Internet Explorer

•Making Home pages Use HTML (Hyper Text Markup Language)

WWW(2)

• Netscape　Navigator

WWW(3)

• Internet Explorer

A Simple HTML Example

<html><head> <TITLE> A Simple HTML Example </TITLE></head> <body>

<H1> HTML is Easy To Learn </H1> <P>Welcome to the world of HTML. This is the first paragraph. While short it is still a p

aragraph!</P> <P>And this is the second paragraph.</P> <P>This is an example of link.

<A HREF="http://www.u-aizu.ac.jp/~toyo">Click it!</A> </P> <P>This is also an example of inline image. Can you find where the original is?<BR>

</body> </html>

Result of the Simple HTML Example

QuickTime˛ Ç∆TIFFÅiLZWÅj êLí£ÉvÉçÉOÉâÉÄ

Ç™Ç±ÇÃÉsÉNÉ`ÉÉÇ å©ÇÈÇΩÇflÇ…ÇÕïKóvÇ≈Ç∑ÅB

E-mail

Outlook

E-mail

Outlook

• Transfer (get or put) files via network.

telnet

• You can access to other computers.

News, BBS

• You can discuss a specific topic and sharing information.

• Chat using text (or even voice).

Multimedia Player

• Play movies or music on the internet.

Advantages of internet

• You can access global information without going there.

• You can communicate with people all over the world.

• You can do business world wide. • You don’t have to consider the national

border. • Distance education and distance medical

care.• Reduced cost of transportation.

Explain what we can do using the following applications.

(1)e-mail (2)WWW(3)ftp (4)BBS(5)telnet (6)chat(7)multimedia player

Internet Technology

• Protocol• Routing

What is Protocol?

• Protocol is the rule for communication. • As you need to follow the traffic rule when you d

rive a car, you need to follow the rule during communication.

• Internet employs a protocol called TCP/IP is mainly used. IP Rule for controlling path along internet. TCP Rule for transfer data without error.

Hierarchy

Application

Presentation

Session

Transport

Network

Data link

Physical

Application

Presentation

Session

Transport

Network

Data link

Physical

Data unit Data unit

Addheader

Removeheader

Communication link

Hierarchical Protcol

What is Routing

• You need to decide a path from source to destination in order to transmit your data.

A Ltd.

B University

C officerouter router

router

destination Port #

C office 1

B university 2

Routing table

Variation of routing

Routing methods Static routing

• You don’t change the route which is decided at the beginning.

Dynamic routing• Depending on the network condition, the optimal route

is automatically found and configured.

Examples of Your Assignments

1. Blog2. Search Engines3. Streaming Service4. Instant Message5. Internet Service Provider6. ADSL7. Peer-to-Peer8. Hot Spot9. XML10. E-commerce

Procedure of group work

• Research Select a topic and do research. Study and discuss the findings.

• Preparation of Presentation Arrange the findings. Consider the effective ways to show your findin

g. Upload the related documents to the Web serv

Midterm Exam Problem(30 min.)

• Suppose you are a non-fiction writer. You are asked to write a non-fiction article about Bali-island on an on-line magazine.

• Describe how you prepare and write the non-fiction article by using the power of internet. Use the following tools as many as you can and explain how you are going to use it. (1)e-mail (2)WWW (3)ftp (4)BBS(5)telnet (6)chat (7)multimedia player

This is just an example of Midterm Exam!

Easy steps to submit your solution

1. Make a file describing your solution on your PC. You can use anything to describe it, word, power point, plain-text, html…

2. Name the file with your student ID. For example, w1111111.doc.

3. Place your file on the shared folder as ordered in the class.

Or you can write your solution with pen and paper, and submit it by your own HAND.

1 Internet Hiroshi Toyoizumi toyo@u-aizu.ac.jp toyo@aoni.waseda.ac.jp.

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