1. EN3515 Lecture 4: Networking and the Internet Net Spaces Case Studies NetworkHardware Network Software Network Standards/Protocols Internet Communication Strategies Evaluating Good Websites

2. Net Spaces

The landscape of Cyberspace

• TheMatrix(main part of cyberspace]

• • The Internet

• • • FTPspace

• • • Telnetspace

• • • Gopherspace

• • • WAISspace

• • • Webspace

• • • Email space

• • Usenet

• • BITNET

• • Commercial Services

• • Private Nets

3. Cyberspace: The Matrix 4. 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

5. FTP Keyword Searcher

There is no way to search the contents of documents at FTP sites.The only alternative is to useArchie- -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.

6. 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.

Example:

Telnet:// personal.cityu.edu.hk

7. Gopher Space

Gopher, aninformation systemdesigned 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

http://www.webopedia.com/TERM/g/gopher.html

8. Gopher Subject Tree

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

http://galaxy.einet.net/GJ/index.html

The Internet search engine history:

http://www.galaxy.com/info/history2.html

9. Case Studies Build apeer-to-peer LAN Build aclient-server LAN BuildNew Media Lab LAN From CityU to Internet 10. 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

Hub (or crossover cable) 11. The buzz word of peer-to-peer network (P2P): kazaa

http://www.download.com#1 download!!

Lets do a search on wired.com with kazaa

server 12. Server/Client Network

Minimal items needed:

• a server with networking software

• 2+ workstation

• a hub (or switch)

• Network cables

Server Link to outsidenetwork(s) 13. 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

14. 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

15. The NML LAN (3) EN Staff LAN CityUStaffLAN Router 24-port Switch 16-port Switch Internet scanner scanner V-Con V-Con NT Unix 16. From LANs to Internet 17. From CityU to the Internet Media Lab 18. 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)

19. 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)

20. Networking Standards

Protocol for connection

• TCP/IP (most popular)

• IPX (Novells 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 255.255.0.0)

21. IP Address

An IP address is a unique identification for any computerconnected 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

22. Classes of IP Address 23. 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

24. 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 cable modem

25. Next Generation of IP Address:IPv6 26. IP Address Each x represents 16 bits, written in hex notation (0 through f) x:x:x:x:x:x:x:x IPv6 address: Each x represents 8 bits in dotted decimal notation (1 through 255) x.x.x.x IPv4 address 27. Other trend of WWW

Connect to the next PPT file

28. Internet Communication Fundamentals & Strategies

Effects : a communication perspective

Uniquefeaturesof the Internet (Web) as a communication medium

Web design: settingreasonable goals

Typesof Web design

Basicelementsof good Web Sites

Dos and donts inWeb design

29. Effects: A Communication Perspective

A simple hierarchy ofcommunicationeffects:

Behavior (actions, performances)

Attitude (beliefs, values, opinions, judgments)

Emotion (feelings, likes)

Cognition(knowledge, information, thinking process)

30. Effective Communication

Communication that comes fromtrusted sources , reaches thetargetedaudience withappropriateformat (means and channels) and content, and achieves the intendedgoals .

31. 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!!)

32. 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.

33. 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/orhttp:// www.worlds.com

34. Internet Communication Goals

General goals:

Information

Entertainment

Service

Marketing

Persuasion

Pure presence

35. Internet Communication Goals (Marketing)

Some specific goals in marketing:

Brand -building

Directmarketing

Onlinesales

Customersupport

Marketresearch

Contentpublishing /services

36. Three Major Types of Web Sites

Brochureware

Show-biz

Utilitarian

37. Brochureware

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

http:// www.spam.com / 38. Show-biz

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

Example: Liptonsmargarinehttp://www.tasteyoulove.com/

39. Utilitarian

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

40. Schools of Web Design

Early ASCII:text

Classic:three-partWeb page

Modern:graphicslabs

Postmodern:fragments

Earlyvirtual : 2D/3D scene, metaphor

41. 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.

42. Early ASCII Page Example 43. 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

44. 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

45. 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/ )

46. Early Virtual: Scene

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

VRML

Adobe Atmosphere

Digital Space

Activeworlds..etc.

http://www.taj-mahal.net/blackBack.htm

47. Elements of Good Web Sites

Good sites are goodcommunities

Good sites are relevant (e.g. personalized content)

Good sites entertain (pleasing)

Good sites do not stand alone (linked)

48. Some Dos in Web Design

Know youraudience

Build ininteractivityand feedback (when necessary)

Provide good and user friendlynavigation

Createconsistent , 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

49. Some Donts in Web Design

Avoid:

monster page overloaded with information

multimedia overkillexample1

meaningless links

clown pants (disorganized pages)

KOOL design (overly fancy but empty sites)

sukers

worst websites

50. 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.

51. Evaluating Standards and Strategies (2)

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

Some basic needs:

1. Factual information 2. Entertainment

3. Socialization 4. Escape/diversion

5. Services 6. Business

52. Evaluating Standards and Strategies (3)

Basic standards:

Accuracy Reliability

Authenticity Readability/Ease

Authority Utility

Accessibility Stability

Currency Links

Interactivity Security

53. 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

54. 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

55. 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.