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EN3515 Lecture 4: Networking and the Internet Net Spaces Case Studies Network Hardware Network Software Network Standards/Protocols Internet Communication Strategies Evaluating Good Websites Net Spaces The landscape of Cyberspace The Matrix (main part of cyberspace] The Internet

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EN3515 Lecture 4: Networking and the Internet

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en3515 lecture 4 networking and the internet

EN3515 Lecture 4:Networking and the Internet

Net Spaces

Case Studies

Network Hardware

Network Software

Network Standards/Protocols

Internet Communication Strategies

Evaluating Good Websites

net spaces
Net Spaces

The landscape of Cyberspace

The Matrix (main part of cyberspace]

The Internet

  • FTP space
  • Telnet space
  • Gopher space
  • WAIS space
  • Web space
  • Email space



Commercial Services

Private Nets

ftp space
FTP Space

The set of all resources accessible through the File Transfer Protocol on the Internet. The resources include directories of files and individual files that might be text or binary (executables, graphics, sound, and video) files. It is among the oldest spaces on the Net and has massive and often obsolete and polluted information on it. It is a major distribution area for software.

Recent trend of Files Transfer on Internet: P2P

ftp keyword searcher
FTP Keyword Searcher

There is no way to search the contents of documents at FTP sites. The only alternative is to use Archie--a tool that indexes the filenames at FTP sites and is good for looking for a software or shareware program of a particular name. Most of these “old world” Internet resources are integrated by WWW today.

telnet space
Telnet Space

Telnet is a protocol for remotely logging into a remote computer. Many Telnet sites still offer valuable and updated information (i.e. card catalogs of libraries). Using Telnet, you can also access your own e-mail account from a long distance.



gopher space
Gopher Space

Gopher, an information system designed at the University of Minnesota, is among the oldest spaces on the Net. Because of the rise of the Web, the Gopher traffic on the Net has declined. Here is the mother of all Gophers at the University of Minnesota


gopher subject tree
Gopher Subject Tree

A good collection of subject-related Gophers is “Gopher Jewels.” A Web-version is at:


The Internet search engine history:


case studies

Case Studies

Build a peer-to-peer LAN

Build a client-server LAN

Build New Media Lab LAN

From CityU to Internet

build a peer to peer network
Build a Peer-to-Peer Network

Minimal items needed:

  • 2+ computers, each with a network card
  • a crossover cable, or a cable and a hub
  • Windows 3.11/95/98 on all computers

(or crossover cable)


the buzz word of peer to peer network p2p kazaa
The buzz word of peer-to-peer network (P2P): kazaa
  • http://www.download.com #1 download!!
  • Let’s do a search on wired.com with “kazaa”


server client network
Server/Client Network

Minimal items needed:

  • a server with networking software
  • 2+ workstation
  • a hub (or switch)
  • Network cables

Link to outside



new media lab lan example
New Media Lab LAN (example)
  • Servers:
    • NT server: primary controller, printer server, file server, and secondary Web server
    • Win2000 server: primary Web server
  • Workstations:
    • 28, running Windows XP, with some of these connected to overhead projector, sound system, scanners, CD-writers, and video conferencing systems
the nml lan 2
The NML LAN (2)
  • Servers, workstations, and printers are connected through 100BASE-T cable (100mps) to designated ports on LAN switches
  • The Lab LAN is connected to the Internet via CityU ATM backbone network (154mps)
  • A router shields the Lab LAN from CityU-EN LAN (i.e., making the Lab a subnet of the LAN), to separate the resources/broadcast messages between the two LANs
the nml lan 3
The NML LAN (3)






EN Staff LAN





24-port Switch

16-port Switch



network vs the internet
Network vs. the Internet
  • Network
    • LAN (private, closed system)
    • WAN (LAN extended to a larger area)
  • Intranet, Extranet, and the Internet
    • Intranet (LAN or WAN using Internet connection): Example: CityU Portal
    • Extranet (Intranet extended to associates)
    • The Internet (a public, open system)
internet vs world wide web
Internet vs. World Wide Web
  • Internet is the physical infrastructure on the global scale whereas WWW is one of the following protocols (i.e., software standards) that run on the Internet:
    • http (for WWW)
    • ftp (file transfer protocol)
    • telnet (remote login protocol)
    • gopher (text-based WWW)
    • mailto (e-mail)
networking standards
Networking Standards
  • Protocol for connection
    • TCP/IP (most popular)
    • IPX (Novell’s proprietary system)
    • NetBIOS/NetBEUI (easy, fast, from Microsoft, for P2P LANs)
  • IP Address
    • Classes (c.l.l.l; c.c.l.l; c.c.c.l)
    • Default gateway (usually the last # in the net)
    • Subnet mask (usually
ip address
IP Address
  • An IP address is a unique identification for any computer connected to the Internet.
  • All IP addresses are in the form of x.x.x.x (where x has 8 bits & ranges from 0 to 255).
  • IP addresses are assigned at levels:
    • Global authority: Network Solutions, Inc.
    • Local authority: the network administrator of your organization
ip address vs internet address
IP Address vs. Internet Address
  • IP address (a 4-quad numeral) identifies a computer connected to the Internet (e.g., 144.214.44.x for our NT server)
  • Internet address (a literal of any length) identifies a Web server (e.g., newmedia.cityu.edu.hk for the NT server) or a subdirectory of a Web server (e.g., newmedia.cityu.edu.hk/en5611)
  • Web server can be a server or a workstation with a fixed IP address and a hardwire connection
dynamic ip address and dial up connection
Dynamic IP Address and Dial-up Connection
  • A dynamic IP address is assigned by a network server during the connection time (often through a dial-up means)
  • A computer is typically assigned a different dynamic IP address each time connected
  • Dial-up connection involves modem-phone line (up to 56kps), or ISDN (Integrated Service Digital Network, 128kps), or ADSL, xDSL, or cablemodem…
other trend of www
Other trend of WWW
  • Connect to the next PPT file…
internet communication fundamentals strategies
Internet Communication Fundamentals & Strategies
  • Effects: a communication perspective
  • Unique features of the Internet (Web) as a communication medium
  • Web design: setting reasonablegoals
  • Types of Web design
  • Basic elements of good Web Sites
  • Do’s and don’ts in Web design
effects a communication perspective
Effects: A Communication Perspective

A simple hierarchy of communication effects:

  • Behavior(actions, performances)
  • Attitude(beliefs, values, opinions, judgments)
  • Emotion(feelings, likes)
  • Cognition (knowledge, information, thinking process)
effective communication
Effective Communication

Communication that comes from trusted sources, reaches the targeted audience with appropriate format (means and channels) and content, and achieves the intended goals.

unique features of internet as a communication means
Unique Features of Internet as a Communication Means

Although the Internet has “inherited” some features from the traditional media, it is distinct in several ways:

  • Interactivity
  • Non-linearity (hypertext and hyperlink)
  • Multimedia capability
  • Porous quality (in pieces)
  • Varying speed (connection speed dependent)
  • Varying browsers (IE, Netscape, Mozilla, Opera, etc.)
  • Varying display (monitors, mostly 14” and 15”)
  • Almost unlimited choices (too many possible links!!)
the 28 8kbps factor
The 28.8Kbps Factor

About one-third of the people using the Internet are connected through 28.8Kbps modems. A bit -- a contraction of the phrase binary digit --is the most elemental unit of computer information, either a 1 or a 0. One byte is made up of 8 bits. Therefore, a 75KB (75,000-byte) file would take 20.8 seconds to transfer at 28,800 bits per second.

web recent trend
Web recent trend

From text-based, to more graphically-represented. From more passively transfer information, to more “interactive,” or even more “immersive” (immersed)

Example: http://flysworkshop.net/as/

Example: http://www.activeworlds.com/ or http://www.worlds.com

internet communication goals
Internet Communication Goals

General goals:

  • Information
  • Entertainment
  • Service
  • Marketing
  • Persuasion
  • Pure presence
internet communication goals marketing
Internet Communication Goals(Marketing)

Some specific goals in marketing:

  • Brand-building
  • Direct marketing
  • Online sales
  • Customer support
  • Market research
  • Content publishing/services
three major types of web sites
Three Major Types of Web Sites
  • Brochureware
  • Show-biz
  • Utilitarian

Brochureware sites are the most commonly deployed ones on the Web. They are normally static, non-interactive and boring “about-my-business”sites.


show biz

Show-biz sites mean two things: First, those misguided attempts to lure visitors to shows of products; second, flashy and showy sites that feature technical dexterity.

Example: Lipton’s margarine http://www.tasteyoulove.com/


Utilitarian sites are those that offer Web surfers a genuine service and experience -- an interactive information/service utility. Federal Express’s (FedEx) site is a classic example.

schools of web design
Schools of Web Design
  • Early ASCII: text
  • Classic: three-part Web page
  • Modern: graphic slabs
  • Postmodern: fragments
  • Early virtual: 2D/3D scene, metaphor
early ascii text
Early ASCII: Text

Influenced by the hierarchical organization common in previous information systems such as Gopher, FTP and Telnet, the early ASCII design style relies heavily on hierarchical organization and links to extend meaning. This school is obsolete.

Example: a telnet web page design.

classic three part web page
Classic: Three-Part Web Page

The classic three-part structure of head, body and column is popular with the use of graphical browsers because the visual impact of a single screen has more visual impact that the scrolling browsers, such as the Lynx browser.

Example: our course site

modern graphic slabs
Modern: Graphic Slabs

Marked by the use of graphics to draw attention, reveal choices and provide ornament, this style runs the gamut of expressions ranging from a single-graphic slab to a mixture of graphics and text often arranged in a grid to reveal functionality.

Examples: compare whitehouse.gov and amazon.com

postmodern fragments
Postmodern: Fragments

Instead of conceiving a page as a fixed structure, a postmodern style generates a page based on user requests by the use of CGI programming to dynamically create web pages and graphics on the fly.

Example: HotWired (http://www.hotwired.com/members/)

early virtual scene
Early Virtual: Scene

The early virtual page involves Virtual Reality Modeling Language (VRML) and can be viewed as an environment in which the room or the scene becomes a unit of attention for the user.

  • VRML
  • Adobe Atmosphere
  • Digital Space
  • Activeworlds..etc.


elements of good web sites
Elements of Good Web Sites
  • Good sites are good communities
  • Good sites are relevant (e.g. personalized content)
  • Good sites entertain (pleasing)
  • Good sites do not stand alone (linked)
some do s in web design
Some Do’s in Web Design
  • Know your audience
  • Build in interactivity and feedback (when necessary)
  • Provide good and user friendly navigation
  • Create consistent, pleasing and efficient look and feel
  • Keep files short and small (45KB or below per page)
  • Content, content, content
  • Link to most relevant resources
  • Use graphics and multimedia only when they are necessary and efficient
some don ts in web design
Some Don’ts in Web Design


  • monster page overloaded with information
  • multimedia overkill example1
  • meaningless links
  • clown pants (disorganized pages)
  • KOOL design (overly fancy but empty sites)


worst websites

evaluating standards and strategies 1
Evaluating Standards and Strategies (1)

Basic assessment:

The Internet is an invaluable source of information, communication, and interaction. It contains diverse information, some of which is good and some of which is garbage.

evaluating standards and strategies 2
Evaluating Standards and Strategies (2)

How to evaluate the information on the Net depends on the purposes and needs of the user.

Some basic needs:

1. Factual information 2. Entertainment

3. Socialization 4. Escape/diversion

5. Services 6. Business

evaluating standards and strategies 3
Evaluating Standards and Strategies (3)

Basic standards:

Accuracy Reliability

Authenticity Readability/Ease

Authority Utility

Accessibility Stability

Currency Links

Interactivity Security

evaluating standards and strategies 4
Evaluating Standards and Strategies (4)

Some good information providers:

1. Academic institutions/experts

2. Tradition mass media

3. Government organizations (i.e., U.S. Census)

4. Major corporations

5. Reputable newsgroups/sites

evaluating standards and strategies 5
Evaluating Standards and Strategies (5)

Some strategies:

1. Lists of top (good) sources

2. Frequently visited sources

3. Frequently linked sources

4. Databases provided by professional providers

evaluating standards and strategies 6
Evaluating Standards and Strategies (6)

Ten things to bear in mind:

1. Traffic might be heavy.

2. Servers can go down.

3. The Net can go down.

4. Resource names can change.

5. Resources can disappear.

6. Resources can be HUGE.

7. Links can break.

8. Your senses might be overloaded.

9. You might be shocked.

10. You can get sick.