Lecture 1 How the Web Works

8/14/2019 Lecture 1 How the Web Works

1/18

Internet Fundamentals

Contact Information: John Anthony Rose, PhD (Associate Professor)

APU Institute of Information Communication Technology

Office Address: B-414

Phone: x4414

E-mail:[email protected]

Web-page: under construction.
mailto:[email protected]:[email protected]


2/18

Texts and References

Our Primary Texts Internet & World Wide Web: How To Program, 3rd Ed.

Authors: H. M. Deitel, P. J. Deitel, and A. B. Goldberg Publisher: Pearson Education (2004) ISBN (Intl Standard Book Number): 0-13-145091-3

HTML for the World Wide Web, 5th Ed. (Elizabeth Castro)

Publisher: Peachpit Press (2003 ISBN: 0-321-13007-3

Other Text Resources: Learning Web Design: A beginners guide to HTML, Graphics, and

Beyond, 2ndEd, (Jennifer Niederst)

Publisher: OReilly (2003) ISBN: 0-596-00484-2

HTML for Dummies (E. Tittel and S. E. James) Wiley (1997), ISBN: 0-7645-0214-X


3/18

Course Syllabus (2007 Spring Q2)

A. Introduction to the Internet and the Web

Lecture 1: Introduction to the Internet Lecture 2: The Netscape Internet Browser

B. XHTML Lecture 3: Introduction to XHTML Lecture 4: Design Fundamentals; XHTML Lists

Lecture 5: HTML Formatting; Simple Tables Lecture 6: Web Page Division and Organization; Complex Tables Lecture 7: Image Maps and Frames

Midterm Exam (In Class) and Final Project Assignment (1st Half).

C. Cascading Style Sheets (CSS) Lecture 8: Introduction to CSS: Creating Styles Lecture 9: Applying Styles: Internal and External Style Sheets Lecture 10: Formatting with Styles I: Font Properties Lecture 11: Formatting with Styles II: Text Properties Lecture 12: Layout with Styles I: Flow and Positioning Lecture 13: Layout with Styles II: The Box Model

-----------------------------------------------------------------------------------------------------------------------------------------------------------------------

Final Exam and Final Project Due (Both 1st and 2nd Halves).


4/18

Course Evaluation (Grading)

The final grade (100%) will be awarded using the followingcriteria for evaluation:

Attendance: 20% Please come to every class.

Mid-Term Exam (In Class): 30%

After Lecture 7

Final Project (Personal Web-page): 15% Due during Exam Week

Final Exam (In Class): 35%

Note: The above schedule and weights are tentative.


5/18

Course Methodology

Lecture materials will be distributed at the beginning of eachclass,

Followed by the Lecture

Where possible, examples will be presented with figures.

Each class is 95 minutes. After each lecture-period:

students will be provided time for practice (as time permits). For a total of 95 minutes (lecture + practice)

Teaching Assistants (TAs) will be available to answer questions

during the practice period.

Note: substantial practice and work beyond the class period

WILL be required.


6/18

Miscellaneous Instructions

Students should bring their own data storage devices:

Necessary for storing work: USB 2.0 Flash Memory

64 MB or higher

Windows XP Compatible

CD-RW

650 or 700 MB

Floppy Disk

3.5, 1.4 MB

These can be purchased at the

APU Book Store.


7/18

Lecture 1 Introduction to the

Internet


8/18

Some Web Resources for Ch.1

www.wikipedia.org The freely available on-line Encyclopedia, Wikipedia

Provides comprehensive discussions of Internet and WWW topics; Available in 10 languages!

www.deitel.com The web-site of one of our primary texts. This site provides various resources

netforbeginners.about.com The About.comInternet for BeginnersGuide

History and workings of the Internet and World Wide Web.

www.learnthenet.com/english/index.html The Learn the Net Website

Contains a complete overview of the Internet and the WWW.
http://www.wikipedia.org/http://www.deitel.com/http://netforbeginners.about.com/http://www.learnthenet.com/english/index.htmlhttp://www.learnthenet.com/english/index.htmlhttp://netforbeginners.about.com/http://www.deitel.com/http://www.wikipedia.org/


9/18

The Internet (The Net)

This course will be focused on the World Wide Web (WWW) Specifically, in the creation ofweb documents (XHTML, CSS). But first, lets talk about the Internet

Which provides the underlying basis for the Web.

The Internet is a publicly accessible, world-wide network of

computer networks This is a Cooperative Effort:

No single company owns the Internet;

The Net Achieves a Virtual Network: The illusion of a single network.

Achieved by governing information transfer by rules and standards.


10/18

A Brief History of the Net

The Net has a D.O.D. origin DARPA: The Defense Advanced Research Projects Agency

ARPANET: The Grandfather of the Internet The first node (computer) was operational on Oct 29, 1969 Big unexpected benefit: Electronic Mail (e-mail).

Use quickly became peaceful

One Primary Goal of ARPANET: Allow many users to send/receive information along the same

phone lines

Rules (protocol) for communicating on ARPANET: Became known as Transmission Control Protocol (TCP)

Information exchanged in small units = packets Exchange by packet-switching

Packets from many users all mixed together; Replaces dedicated lines between senders and receivers. Drastically lowers costs.

TCP ensures correct, intact delivery of each packet.


11/18

The Internet Protocol

As the Net evolved Organizations world-wide began implementing their ownnetworks; Both intranets (within each organization) And internets (between organizations).

Using a wide variety of hardware/software

Big Challenge: develop a set of rules allowing them ALL to communicate!

To achieve smooth packet travel, these rules must: Provide a unique address for each computer on the Net. Be communicable to all computers on the Net.

This set of rules is called the Internet Protocol (IP). The combined set of protocols: TCP/IP

operates on top of . The first TCP/IP Network:

National Science Foundation: USFNet (Jan. 1, 1983)


12/18

Internet Increasing Exponentially

At first, the Internet was used mostly by NationalLabs/Universities However, the military began large-scale use; Also, the Government eventually allowed commercialuse.

Growth since then has been monitored.

See figure Growth is Exponential

(Note the log scale) Dec, 2003: > 10

8clients.

Jan, 2006: > 109

clients!

Old worry: Net will become saturated! and performance will decline. However, the reverse is actually true:

Businesses need to optimize intranetperformance. Thus

Information carrying capacity (bandwidth)

has increased tremendously.


13/18

The World Wide Web (WWW)

The World Wide Web (WWW) was created in 1990 By Tim Berners-Lee ofCERN (Switzerland) This system allows users to view multimedia-based documents:

Text, Graphics, etc.

Use of the Web exploded in 1993 With creation of the Mosaic web-browser by the NCSA

The National Center for Supercomputing Applications Mosaic featured a user-friendly Graphical User Interface (GUI)

The WWW is a publicly-accessible, world-wide network ofdocuments Thus, the Web is not the same as the Internet.

Rather, the Web is a service, that operates ON the Internet.

In this course, our focus is on the Web Specifically, we will focus on creation of Web documents:

Mainly via XHTML and CSS (possibly a little JavaScript).

But first, lets briefly discuss how the Web works.


14/18

Some Basic WWW Terms

The Web is the combination of 4 simple ideas: Hypertext:

the ability to move within or between documents, throughinternal connections (hyperlinks);

Resource Identifiers: the ability to locate a particular resource (computer, printer, etc)

on a network Via Universal Resource Locators (URLs) more on this next lecture.

The Client-Server model of Computing: Client software/computers make requests for resources (data)

A program called a Web Browser.

Serversoftware/computers provide the requested resources.

Markup Language: Characters included within the textindicate how the text should

be formatted HTML = Hypertext Markup Language


15/18

How the Web Works These 4 ideas work together on the Web, as follows:

1. A Client program (browser) requests information from a Server; e.g., a Web-page or a file.

Service provided by an Internet Service Provider (ISP)

2. The Server is identified using its Network Address; From the Server part of the informations URL.

Accomplished by a special server:

A Domain Name System (DNS) server.

3. The requested information is quickly returned to the client.

4. The Browser displays the returned information Typically on a computer screen.

5. The Markup Language controls how the retrieved text is displayed. As a Web Page, integrating all text, images, links, etc, as directed.

Hyperlinks in the Web Page then allow page-to-page travel

Often called web surfing.

Web pages are often grouped into structured units, orWeb-

sites.


16/18

World Wide Web Consortium (W3C)

In 1994, Tim Berners-Lee founded theW3C Mission: to develop non-proprietary technology for the Web.

Non-proprietary = Freely accessible to everyone.

Primary Goal:Establish Universal Web accessibility, Regardless of language, culture, or ability.

Thus, W3C is the Webs United Nations. Another Goal: Web Standardization:

Establish standard technologies for uniform Web use: Recommendations.

Some examples:

HTML Hypertext Markup Language (legacy tech.: out-dated) XML Extensible Markup Language XHTML Extensible Hypertext Markup Language CSS Cascading Style Sheets

We will discuss all of these, in the coming lectures.

Visit W3C Web-page, at:http://www.w3.org
http://www.w3.org/http://www.w3.org/


17/18

Conclusion

In this Lecture, we have introduced: The Internet: A world-wide network of computers

The World Wide Web: A world-wide network of documents

and the relationship between these two terms.

Along with brief discussions of: Internet protocols for communication (TCP/IP); Basic Web Functionality.

In the next Lecture, we continue our discussion With a detailed tour of a popular Internet Browser: Netscape.

A tool for Web Browsing. We will then discuss various other Web services:

Electronic mail (e-mail) Instant Messaging

And become familiar with the differences between the various

browsers.


18/18

Task for Today

Open the Internet Browser, Netscape 7.2:Then, visit each of our suggested web resources:

The Web Encyclopedia, Wikipedia

Our textbooks web-site (Deitel.com).

The About.comInternet for BeginnersGuide

The Learn the Net Website

Also visit the Web page of the WWW consortium.

Documents

Lecture 1 How the Web Works