- 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]
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.
- 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
-
- 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
-
- a server with networking software
Server Link to outsidenetwork(s) 13. New Media Lab LAN
(example)
-
- NT server: primary controller, printer server, file server, and
secondary Web server
-
- Win2000 server: primary Web server
-
- 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
-
- 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:
-
- ftp (file transfer protocol)
-
- telnet (remote login protocol)
20. Networking Standards
-
- IPX (Novells proprietary system)
-
- NetBIOS/NetBEUI (easy, fast, from Microsoft, for P2P LANs)
-
- 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
- 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:
- Non-linearity (hypertext and hyperlink)
- 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
35. Internet Communication Goals (Marketing)
- Some specific goals in marketing:
- Contentpublishing /services
36. Three Major Types of Web Sites
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
- Classic:three-partWeb page
- 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.
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.
- 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
- 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
- monster page overloaded with information
- multimedia overkillexample1
- clown pants (disorganized pages)
- KOOL design (overly fancy but empty sites)
50. Evaluating Standards and Strategies (1)
- 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 .
- 1. Factual information 2. Entertainment
- 3. Socialization 4. Escape/diversion
52. Evaluating Standards and Strategies (3)
- Authenticity Readability/Ease
53. Evaluating Standards and Strategies (4)
- Some good information providers:
- 1.Academic institutions/experts
- 3. Government organizations (i.e.,U.S. Census )
- 5. Reputable newsgroups/sites
54. Evaluating Standards and Strategies (5)
- 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.
- 4. Resource names can change.
- 5. Resources can disappear.
- 6. Resources can be HUGE.
- 8. Your senses might be overloaded.