1 CP586 © Peter Lo 2003 Multimedia Communication Multimedia and the Internet.

CP586 © Peter Lo 2003 1

Multimedia CommunicationMultimedia Communication

Multimedia and the Internet

CP586 © Peter Lo 2003 2

The InternetThe Internet The key to Internet operation is Client Server model in

which computers, called clients, can simultaneously access a server.

Internet Backbone: Provides connectivity and services between servers.

It relies on high speed communication lines to rapidly move information and commands between servers and individual work stations.

DNS, TCP/IP, Internet functions, origin of the WWW and web authoring.

HTML overview.

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Some services found on the InternetSome services found on the Internet e-mail Web File transfer Chat Message board Instant messaging

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How did the Internet originate? How did the Internet originate?

Goal:

To function if part of network were disabled

Became functional September

1969

Goal:To allow

scientists at different

locations to share information

ARPANETNetworking project

by Pentagon’s Advanced Research

Projects Agency (ARPA)

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Who provides the Internet’s Who provides the Internet’s structure today?structure today?

Government

Cable companies

Satellite companies

Telephone companies

Networks from corporations, commercial

firms, and other companies

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How has the Internet grown?How has the Internet grown? Today

More than 100 million host nodes

1984 More than 1,000 host nodes

1969 Four host nodes

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Who controls the Internet?Who controls the Internet? Nobody; it is public, cooperative, and an independent

network Several organizations set standards

World Wide Web Consortium (W3C)

• Oversees research, sets standards and guidelines

• Tim Berners-Lee, director

Internet2 (I2)

• Internet-related research and development project

• Develops and tests advanced Internet technologies

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What are ways to access the What are ways to access the Internet?Internet?

1 Regional ISP

2 National ISP

3 OSP(Ex. AOL)

4 Wireless Internet Service Provider

local call

long-distance call

1

local call

2local call

toll-free call

3

local call

4

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How can you connect to the Internet?How can you connect to the Internet? Very high-speed connection Digital subscriber line (DSL) and cable modem Dial-up access

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What are three parts of an What are three parts of an Internet connection?Internet connection?

BackboneClient Server

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How might data travel the Internet using a How might data travel the Internet using a telephone line connection?telephone line connection?

How might data travel the Internet using a telephone line connection?

Step 1Step 1Step 2

Step 1Step 2

Step 3

Step 1Step 2

Step 3

Step 4

Regional ISP

Step 1Step 2

Step 3

Step 4

Step 5

Regional ISP

National ISP

Step 1Step 2

Step 3

Step 4

Step 5

Step 6

Regional ISP

National ISP

National ISP

Internet backbone

Step 1Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Regional ISP

Local ISP

National ISP

National ISP

Internet backbone

Step 1Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Regional ISP

Local ISP

National ISP

National ISP

Internet backbone

1: Request data from the a server on Internet.

2: Modem converts digital signals to analog signals.

3: Data travels through telephone lines to a local ISP.

4: Data passes through routers.

5: Regional ISP uses leased lines to send data to a national ISP.

6: National ISP routes data across the country.

7: National ISP passes data to local ISP.8: Server sends

data back to you.

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Internet protocol (IP) addressInternet protocol (IP) address Number that uniquely identifies each computer or

device connected to Internet

IP address 199.95.72.10

first part identifies network

last part identifies specific

computer

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Domain nameDomain name Text version of IP address

IP address 199.95.72.10

Domain name scsite.com

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What is a URL?What is a URL? Unique address for Web page located on Web server

protocol domain name path

http://www.nationalgeographic.com/travel/index.html

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The InternetThe Internet The Internet is a vast network of interconnected

computers that can share and exchange information.

Started in 1960’s & was called “ARPAnet” The Internet is often called the Information Super

Highway and the World Wide Web. Web pages are based on the HTML standard.

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Internet BasicsInternet Basics HTTP: is a connection orientated protocol

designed for the rapid transport of files. HTTP uses a simple protocol that supports

negotiation between the client and server. This negotiation allows web browsers and servers

to be developed independently of emerging technologies.

Eg. Get, put, checkout, delete, text search.

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Internet Naming StructureInternet Naming Structure INS uses labels separated by periods. It uses a hierarchical structure where organisations

are grouped into primary domain names. com : Commerce, gov : Government, edu :

Educational, mil : Military, Net : Internet Network Support Centres, org : Another Organisation, au : Australia.

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Standardised AddressingStandardised Addressing TCP/IP : Transport Control Protocol / Internet

Protocol. The Internet uses TCP/IP. Each node on the Internet has an associated IP

address X.W.Y.Z and a physical address of the form XX:XX:XX:XX. (MAC)

X,W,Y,Z are integer values ranging 0-255. IP is to postcode as MAC is to address.

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ReferenceReference Discovering Computers World 2003 (Ch. 2) Multimedia, Technology and Applications

(Ch.10)