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					   SMAD 307
Multimedia for the Web
           Internet Basics
              IP Addresses
• Every computer is a “node” on the
Internet and has a unique IP Address

• Four numbers between 0 and 255


• Example: 134.126.47.45
            Internet Basics
             IP Addresses
 • Each segment is an 8-bit number




• More than 4-billion IP addresses are
possible
 4,294,967,296 = 256 * 256 * 256 * 256
               Internet Basics
                  IP Addresses
• Blocks of IP addresses are allocated to
research, education, government, corporations,
and Internet Service Providers
http://www.iana.org/assignments/ipv4-address-space


• Individual IP addresses are in turn allocated
to individual computers
             Internet Basics
 “Dynamically Assigned” IP Addresses
• Modem Dial-Up connections: Dynamic




• ISPs pay for a “block”
• They have fewer IP addresses than
customers
              Internet Basics
          “Static” IP Addresses
• Dedicated connections: Static




• Each computer gets a dedicated IP that
doesn’t change from session to session
• One IP address needed for each customer
            Internet Basics
         Domain Name System
• IP Addresses are hard to remember

• Domain Names are mnemonic devices

• Every domain name has specific IP address

               Example:
     www.internic.net = 207.151.159.3
             Internet Basics
         Domain Name System
          i.e. www.beaweb.org
• Organized by levels. Top level on right
      • TOP LEVEL DOMAINS (TLDs)
com: commercial (now, any type)
edu: educational institutions
org: non-commercial organizations
net: sites about the Internet
gov: U.S. government sites
mil: U.S. military sites
            Internet Basics
        Domain Name System
         i.e. www.beaweb.org
       SECOND LEVEL DOMAINS
            beaweb.org
             yahoo.com
           whitehouse.gov

• Companies/organizations “register” for
these names with an accredited registrar
                  Internet Basics
           Second Level Domains
         ????????????????????.com
        Can be any of 61 characters
    • 26 Letters (A – Z)
    • 10 Numbers (0 - 9)
    • Hyphen (except it can’t be the first or last
    character)
        How many different domain names?
433,018,769,429,481,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000

• Except, the one you want won’t be available 
             Internet Basics
         Domain Name System
          i.e. www.beaweb.org
         THIRD LEVEL DOMAINS
            www.beaweb.org
             mail.beaweb.org
             ftp.beaweb.org
• Owned by people with second level domains
• Used for different purposes
• Each is attached to its own IP address
                Internet Basics
         Domain Name System
           COUNTRY DOMAINS
 • Each country has its own 2-letter domain
    ca = Canada       www.internic.ca
    au = Australia    www.mcg.org.au
    ke = Kenya        www.museums.or.ke
    no = Norway       www.uio.no
    ro = Romania      www.infoeuropa.ro/
• Each country maintains their own second
level domains
               Internet Basics
          Domain Name Servers

• IP addresses must be “mapped” to domain
names

• When you type: www.acmewidgets.com….
  - Your computer connects to a “Domain
    Name Server”
  - The “DNS” server looks up the address
    to see its IP address and sends it to you
  - Your computer then uses the IP address
               Internet Basics
          Domain Name Servers

• IP addresses may change, but domain
names won’t have to.

• When you “register” a domain name……
  - You are creating an entry in the file kept by
    DNS servers


        http://his.com/cgi-bin/nslookup
            (enter a domain name)
         Internet Organization
• No central authority for control of content
• There is “management” through ICANN
(Internet Corporation for Assigned Names & Numbers)
       Internet Organization
   Internet Corporation for Assigned
     Names and Numbers (ICANN)
• Manages the domain name system, and the
allocation of Internet Protocol numbers.
• Funded through the many registries and
registrars that comprise the global domain
name and Internet addressing systems

• Vinton Cerf: Chairman of the Board
(Recall: He co-invented TCP/IP)
         http://www.icann.org/
          Internet Organization
     Internet Corporation for Assigned
       Names and Numbers (ICANN)
• A nonprofit corporation whose board of directors is
accountable to the attorney general of the state of
California and under the authority of the U.S. government.

• Established in 1998 by Clinton Administration.
• Until 1998, the Internet was overseen almost exclusively by one
man: Jon Postel, a computer science professor at the University
of Southern California.
• 1960s: Postel was a Graduate Student
• Among the handful of engineers who built the Internet.
• For the next 30 years, he managed it on behalf of the
Department of Defense's Advanced Research Projects Agency.
            Internet Organization
      Internet Corporation for Assigned
        Names and Numbers (ICANN)
• 2004: International community favors transferring
authority over the Internet to the UN

• 2005: Commerce Department statement – The United States
will retain its authority over ICANN.

    • National Telecommunications and Information
    Administration (Part of Commerce Dept.) Statement:

http://www.ntia.doc.gov/ntiahome/domainname/USDNSprinciples_06302005.htm
        Internet Organization
  ICANN’s 3 Supporting Organizations
• Address Supporting Organization
(Manages the IP address space)

• Generic Names Supporting Organization
(Sets Policy and Manages “generic” TLDs)


• Country Code Names Supporting Organization
(Sets Policy and Manages “country-code” TLDs)
      Internet Organization
Generic Names Supporting Organization
          Administers the gTLDs


                EXAMPLES
• http://www.beaweb.org (ORG is the gTLD)
• http://www.yahoo.com (COM is the gTLD)
     Top Level Domains
   Top Level Domains - TLDs
            Two Types
• Generic TLDs (gTLDs) (aka “Global”)
       The Original Six gTLDs - 1985
                   .com
                    .edu
                   .gov
                    .mil
                    .net
                    .org
• Country Code TLDs (ccTLDs) - Examples
              .uk (Great Britain)
              .fr (France)
              .tv (Tuvalu)
        Top Level Domains
Newer Generic Top Level Domains
    .aero *                      .biz *
    .cat #                       .coop *
    .info *                      .jobs #
    .mobi #                      .museum *
    .name *                      .post #
    .pro *                       .tel #
    .travel #

* Selected in 2000. Final approval came a bit later. All but
.pro existed by the end of 2001.
# Selected in 2005. Some still not operational (.post & .tel)
          Top Level Domains
gTLDs Proposed/Under Consideration
.xxx (Also proposed in 2005.   Later rejected.)

.mail (Under consideration. Attempts to eliminate/reduce
spam by “maintaining a list of domains authenticated as
both not belonging to known spammers, and providing
verified contact information.” Would use existing domain
name with .mail appended i.e. jmu.edu.mail).

.kid (Proposed by European Parliament for children.
Monitored by an independent authority.)

.kids (kids.us)
                 Top Level Domains
    gTLDs Proposed/Under Consideration
                       So-Called: “GEO gTLDs”
      (Spawned by Success of .cat. Rationale is the the web is
                 becoming more regional and local.)
  .berlin (Berlin)
  .bzh (Brittany - Breton Culture and Language)
  .cym (Cymraeg - Welsh Culture and Language)
  .gal (Galicia - Nationality of NW Spain)
  .nyc (New York City)
  .sco (Scotland)

•There is also a proposal for .geo - an attempt to classify sites geographically.
               Top Level Domains
               Three Types of Oversight
• Sponsored domains (such as .coop)
- Open only to a defined community represented by the Sponsor.
- The sponsor does the work of determining eligibility and sets
policy for this “narrower” community.
• Unsponsored/Restricted domains (such as .gov & .edu)
-Can only be used by organizations that meet the eligibility criteria.
.gov can only be used by governments, .edu can only be used by
educational institutions.
• Unsponsored/Unrestricted domains (such as .com
.org .net)
- Most non-commercial organizations use .org, and most commercial
businesses use .com. to characterize their operations.
              Top Level Domains
              Unsponsored/Restricted
      .edu                    .gov                          .mil
    Educause         General Services Admin.   Defense Info. Systems Agency
(www.educause.edu)       (www.gsa.gov)                (www.disa.mil)
                         Top Level Domains
                  ICANN Sponsors/Operators
                                                                      -Unsponsored/Unrestricted
                                                                      domains have operators
                                                                      - Unsponsored/Restricted
                                                                      domains have operators.
                                                                      - Sponsored domains have
                                                                      sponsors.
                                               |
     .com .net                      .org                        .aero                    .biz
      Verisign            Public Interest Registry          SITA INC B.V.              Neulevel
  (www.verisign.org)          (www.pir.org)                 (www.nic.aero)         (www.neulevel.biz)

           .cat                    .coop                     .info                   .jobs
     Fundació puntCAT        DotCooperation LLC,            Afilias            Employ Media LLC
     (www.domini.cat)          (www.nic.coop)            (www.nic.info)         (www.nic.jobs)

                 .mobi                        .museum                          .name
        Nokia/Vodafone/MS/Afilias            MuseDoma                   Global Name Registry
             (www.nic.mobi)              (musedoma.museum)                (www.nic.name)

        .post                  .pro                        .tel                      .travel
Universal Postal Union      Registry Pro             Telnic Limited        The Travel Partnership Corp.
  * Not Yet Official       (www.nic.pro)             (www.nic.tel)             (www.travel.travel)
           Top Level Domains
                      .com .net
                 Verisign (Operator)
                 (www.verisign.org)
• Unsponored/Unrestricted: Anyone can get these
- Verisign formerly knows as “Network Solutions”
- Once registered all the domain names (.com .net .org)
- Gave up .org Jan. 1, 2003
- A diversified company today offering a range of
business services, including digital certificates.
- Still manages the domain name database

• .com: Considered the MOST valuable TLD
           Top Level Domains
                          .org
          Public Interest Registry (Operator)
                    (www.pir.org)
• Unsponored/Unrestricted: Anyone can get .org
- “Public Interest Registry” began as operator on
Jan. 1, 2003
- Intended for non-profit organizations
- PIR is itself a non-profit corporation


 • .com: Considered the MOST valuable TLD
           Top Level Domains
                       .aero
               SITA INC B.V. (Sponsor)
                   (www.nic.aero)

• Sponsored/Restricted: Aviation Community
   • Airports, airlines, organizations, agencies
   & individuals
• The first one based on a single industry

• Example: http://www.srilankan.aero
             Top Level Domains
                           .biz
                    Neulevel (Operator)
                    (www.neulevel.biz)
• Unsponsored/Restricted: Businesses eligible
(For “bona fide business or commercial use”, but in reality there
is not legal definition making this a de facto “unrestricted”
domain --available to anyone.)
(Unsponsored here means they don’t set policy, just
enforce the rules set by ICANN)

• .com domains are in short supply
• Not considered as valuable as .com
           Top Level Domains
                        .cat
             Fundació puntCAT (Sponsor)
                  (www.domini.cat)

• Sponsored/Restricted
• Not restricted geographically like a ccTLD
• Though Catalon area is NE Spain (Barcelona) and SE
France
• The Catalon people were reluctant to use .es (Spain) or .fr
(France), since desire independence.
• Town of Girona in “Catalonia” used .gi (www.ajuntament.gi)
for their domain name. (.gi is ccTLD for Gibraltar)
    • The Spanish town using .gi embarrassed the Spanish
    government, which seeks sovereignty over Gibraltar. This
    seemed to endorse Gibraltar independence.
          Top Level Domains
                      .coop
          DotCooperation LLC, (Sponsor)
                (www.nic.coop)

•   Sponsored/Restricted: Only for “cooperatives”
•   For businesses and organizations that operate
    according to the 7 cooperative principle

             1.   Voluntary and Open Membership
                2. Democratic Member Control
              3. Members’ Economic Participation
                4. Autonomy and Independence
            5. Education, Training, and Information
              6. Cooperation Among Cooperatives
                  7.   Concern for Community
           Top Level Domains
                        .info
                 Afilias (Operator)
                  (www.nic.info)

• UnSponsored/UnRestricted: Anyone can get
• The most successful “new” domain
• Used by business, individuals and organizations
• Example: http://mta.info (NYC Metropolitan Transit
   Authority)
         Top Level Domains
                   .jobs
         Employ Media LLC (Sponsor)
               (www.nic.jobs)

• Sponsored/Restricted: Employment Related Sites
• Approved in 2005
• Makes it easy for someone to find the jobs
  information with a company…
      Examples: microsoft.jobs & walgreens.jobs
   …though most simply forward to a .com URL.
           Top Level Domains
                    .mobi
    Nokia/Vodafone/Microsoft/Afilias (Sponsor)
                (www.nic.mobi)
• Sponsored/Restricted: Managed by a large group
• For sites intended to be delivered to mobile
  phones and other small mobile devices.
• Very new (2006), but making big headlines:
  • 6-Figure sales for…
        sportsbook.mobi, flowers.mobi, fun.mobi
•    Criticized for not being “device independent” (We are
    supposed to be designing sites that can work on multiple
    platforms via CSS)
•   Praised because sites will have to look good on the small
    screens
            Top Level Domains
                        .museum
                   MuseDoma (Sponsor)
                   (musedoma.museum)

•   Sponsored/Restricted: Restricted to museums,
    museum organizations and individual members
    of the museum profession
• Example: historyofscience.oxford.museum

        (Like others, many URLs forward. This will happen until
    there’s greater acceptance of the .museum gTLD.)
          Top Level Domains
                      .name
               Global Name Registry
                 (www.nic.name)
•  UnSponsored/Restricted: Restricted to individuals
  and families (real names, nicknames, screen names,
  pseudonyms or other personal names)
• Can be registerd on…
  • Second level: steve.name
  • Third level: steve.anderson.name
• Can register for 10 year periods
• Is possible to register an email address in the form
  of steve@anderson.name, instead of
  steve@steve.anderson.name (email for life)
         Top Level Domains
                       .post
               Universal Postal Union
                 * Not Yet Official

• Sponsored/Restricted
• Universal Postal Union is an international
  organization based in Switzerland.
• It wants to offer its TLD for national postal
  agencies, such as "usa.post”
• Will provide a “trusted, stable and secure
  standard identifier for the postal community.”
• NOT YET APPROVED
             Top Level Domains
                             .pro
                          Registry Pro
                         (www.nic.pro)

•   UnSponsored/Restricted: Accountants, lawyers,
    physicians, and other professionals
•   “Each registrant's identity and professional license
    information will be verified against relevant public and third-
    party databases prior to domain name activation.”
• Will allow sub-distinctions: i.e.
  JamesRClarke.med.pro or JamesRClarke.law.pro or
  JamesRClarke.cpa.pro
• Has not become popular
          Top Level Domains
                         .tel
                   Telnic Limited
                   (www.nic.tel)
•  Sponsored/Restricted: Restricted to “Internet
  Communication Services”
• .mobi sponsor is contested, arguing this is similar
• .tel allows a person’s or company’s contact
  information to be part of the DNS record. A user
  could call or send a text message directly from the
  site. If your company has a .tel site, others will
  have access to your contact information, even if it
  changes. Good for VoIP, SMS etc.
• NOT YET AVAILABLE
          Top Level Domains
                       .travel
             The Travel Partnership Corp.
                 (www.travel.travel)
•  Sponsored/Restricted: Restricted to travel
  agents, airlines, B&Bs, tourism bureaus etc.
• Is supposed to provide a higher level of trust for
  the consumer that the travel information is
  legitimate.
            Top Level Domains
              Accredited Registrars
 - ICANN and Sponsors/Operators accredit other
 companies to do registrations and these “registrars”
 charge what they want, BUT…
 - Verisign charges a fee for maintenance of the
 database…
    Prior to Oct. 15 2007:    After Oct. 15 2007:
    .COM $6.00 | .NET $3.50   .COM $6.42 | .NET $3.85

 - ICANN charges a fee of 25 cents per each year for
 .com, .net, .org, .info, .biz, .name, .jobs, .mobi

http://www.icann.org/registrars/accredited-list.html
      Acquiring a Domain Name

• Some registrars (see list below) also offer
“Web Hosting.”
http://www.icann.org/registrars/accredited-list.html
        Acquiring a Domain Name
            Domain Name Conflicts
       FOUR CATEGORIES OF CONFLICT
1. Infringement: …on another company’s trademark
- Attempt to make money selling goods or services using another’s
    trademark

2. Speculation: (“CyberSquating”)
- Held in reserve hoping the trademark owner will buy it.

3. Character String Conflicts:
- More than one legitimate, non-speculative user

4. Parody:
- Domain names for acts of parody, preemption, or
   expression
   Acquiring a Domain Name
      Domain Name Conflicts



  Excellent Source of Information:
http://www.domainhandbook.com/dd.html
        Acquiring a Domain Name
            Domain Name Conflicts
1. Infringement: (“Trademark” Infringement)
- A trademark is either a word, phrase, symbol or design which
    identifies and distinguishes the source of the goods or
    services of one party from those of others


• Mattel , manufacturer of the popular Barbie dolls,
sued Internet Dimensions Inc. in Fort Lauderdale,
Fla., for trademark infringement when it discovered
a porn site called BARBIESPLAYPEN.COM


• A judge ordered them to stop using the trademark
        Acquiring a Domain Name
            Domain Name Conflicts
2. Speculation: (“CyberSquating”)
             (Attempting to “extort” money)

• Dennis Toeppen: (Owner of an Illinois ISP)
- Registered: panavision.com (among others)
- Established a "web site" displaying aerial views of Pana,
Illinois
- When Panavision called asking for the name, Toeppen
offered to discontinue its use for $13,000


• Court ruled he diluted the value of the
trademark. Panavision won!
        Acquiring a Domain Name
            Domain Name Conflicts
3. Character String Conflicts
- More than one legitimate, non-speculative user

• Words like prince, united, glad
• The word “glad” is trademarked by more than 200
companies ranging from cosmetics to detergents to
electrical apparatus
- Was disputed: “Glad Bag” people won.

 Case Example: utahrealestate.com
       Acquiring a Domain Name
            Domain Name Conflicts
4. Parody
- Domain names for acts of parody, preemption, or expression

          ?????.stinks AND ?????.sucks
 • Registering negative names such as….
 netscapesucks.com
 walmartcanadasucks.com
• Are there “FREE SPEECH” issues here?
• Companies buy the “dirty domains”
- Schwab, WalMart, Vail Resorts, and Volvo Cars
have registered offending domains.
            Acquiring a Domain Name
                   Additional Problems
            “Reverse Domain Name Hijacking”
- The act of a bigger, richer, more influential company or
   individual who threatens you with lawyers and legal fees in
   a fight over a domain name to which you may have a lawful
   right.
                         “Stealth URLs”
-       Addresses intended to trick confused users into visiting
        their site. i.e. whitehouse.com versus whitehouse.gov

        “Registering Commonly Misspelled Words”
    -    Registering domain names based on commonly misspelled
         words. i.e. http://www.consumereports.com
      Acquiring a Domain Name
 Domain Name “Dispute Resolution”
                THREE OPTIONS
1. Submit a complaint to an “Approved Dispute
Resolution Service Provider”
http://www.icann.org/udrp/approved-providers.htm


• For “abusive” registrations (i.e. CyberSquating)
  “Cyber squating”: registering a domain name in hopes of
     selling it back to the trademark owner for a profit

 • Expedited Process
     Acquiring a Domain Name
Domain Name “Dispute Resolution”

2. “Court Litigation”
 • Hire a Lawyer
 http://www.domainnamedisputelawyers.com/


3. “Hire a Company to Negotiate”
 The VeriSign® Recovery and Acquisition Services team
 helps you obtain the brand name you want without
 revealing your identity and without incurring high legal
 fees. On your behalf, we attempt to identify, negotiate, and
 acquire restricted domain names in any top-level domain.
               Internet
• internet: Any Network of Networks
• Internet: A Network of Networks
Using TCP/IP
- (TCP/IP = Transmission Control
Protocol/Internet Protocol)
      World Wide Web

• A distributed hypermedia system.
• A vast collection of interconnected
documents, spanning the world.
• The WWW “rides” on the Internet.
• The WWW is essentially an Internet
Protocol (i.e. HTTP)
        How the Internet Works
 Circuit Switching vs. Packet Switching


 • Part of what makes the Internet
 “survivable’ is the way it sends data


• Voice Telephone Messages = Circuit Switching
• Internet Messages = Packet Switching
       How the Internet Works
            Circuit Switching




• Public Switched Telephone Network
• The path stays open throughout the length of
communication
• Constant Bit-Rate: Bandwidth is “fixed”
       How the Internet Works
             Packet Switching




• Good for “bursty” traffic (Computers)
• Packets go different routes
        How the Internet Works
               Packet Switching

• More than one communication can share a
given link at the same time

• ARPANET was the first “Packet Switching”
network
• Connections are managed via………
   - Routers: Figure out the most efficient route
         (“Routers are like regional post offices”)
  - Bridges: Less “intelligent” than routers.
    Simply pass messages along.
How the Internet Works
   Packet Switching
        How the Internet Works
                    Packets



1. Source: The IP address of the computer sending the
  packet
2. Destination: The IP address of the destination
   computer
3. Length: The length of the packet in bytes
4. Number: The total number of packets in the
   complete message
5. Sequence: The number of this packet in the whole
   list of packets making up this communication.
       How the Internet Works
                 Ethernet
• Used to catch the “Ether Bunny”
• High speed connection to go the “last mile”
• The most common way to carry the Internet
  on local area networks
        How the Internet Works
                  Bandwidth
             Two Ways to Move Data
Atoms    •    Packaging, Shipping & Inventory Costs
         •    Slow Movement
         •    Data Can't Be Changed
         •    Finite Limit of Space
         •    Not Always Accessible
         •    High Cost of Access

Bits     •    Low Cost
         •    Instantaneous Movement (Speed of Light)
         •    Data Can Be Easily Changed
         •    Virtually Infinite Space
         •    Universally Accessible
      How the Internet Works
                Bandwidth
• Bandwidth = How much data, how fast?
• For some things, “ATOMS” work better




 “Never underestimate the bandwidth of a station
 wagon full of tapes hurtling down the highway!”
        How the Internet Works
           Bandwidth Definitions
• The capacity of a network to transmit data is called
Bandwidth, and it is expressed in bits per second.
• Sending data through a phone wire is like sending
water down a pipe. The wider the pipe, the more
information you can send, faster.
        How the Internet Works
           Bandwidth Definitions

• The narrower the bandwidth, the less amount of
information that can be "squeezed" through it at any
one time, and the longer it takes.
How the Internet Works
     Bandwidth
How the Internet Works
4 Electronic Delivery Paths
  • Telephone
  • Cable
  • Satellite
  • Terrestrial Broadcast
        How the Internet Works
                 Telephone
                   • Lines Radiate Out From a Point
                   (Star)
                   • You Can Follow Your Phone Wire
                   Back to the Phone Company
                   • Bits Go to Individuals

                   • Two-Way (Upstream/Downstream)

                   • Not Good for Point-to-Mass

“Modems” / “ISDN” / “xDSL”
        How the Internet Works
                    Cable
                • Lines Connect Like Christmas Tree
                Lights (Ring)
                • Small Cables Join Larger Cables

                • Bits Go to Everyone
                • Two-Way (Upstream/Downstream) BUT
                More Downstream = Asymmetrical
                • Good for Point-to-Mass

“Cable Modem”
How the Internet Works
          Satellite

      • All Bits Go By Everyone
      • Good for Point-to-Mass
      • Good for Remote Locations
      • One-Way (Downstream)




     Upstream handled via modem
 http://www.skycasters.com/
       How the Internet Works
            Two-Way Satellite

               • NOW AVAILABLE
               • Both Upstream and Downstream
               • Excellent for Remote Locations
               • NO PHONE LINE NEEDED




http://www.starband.com
http://www.FastInternetUSA.com/starbandhow.htm
     How the Internet Works
        Terrestrial Broadcast

                • All Bits Go By Everyone
                • One-Way (Downstream)
                • Good for Point-to-Mass
                • Modem Used for Upstream
                • Broadcasters Want This Very Much!
“DTV” Service
        How the Internet Works
                “Broadband”
      A term to describe “fast” connections

   Common “In-the-Home” Broadband Today

• ISDN (Integrated Services Digital Network)
• DSL (Digital Subscriber Line)
• Cable Modem
          How the Internet Works
                          ISDN
        Integrated Services Digital Network
• Uses regular “twisted-pair” copper telephone lines
                      Symmetrical
     - Same speed Upstream and Downstream

   • Two Variations:
          - Single-Channel ISDN: 56 kbps
          - Dual-Channel ISDN: 128 kbps

This technology is being “leapfrogged” by DSL and Cable Modem
         How the Internet Works
                      DSL
             Digital Subscriber Line
• Uses regular “twisted-pair” copper telephone lines
                  Asymmetrical
    - Downstream: Speeds range from 512
    kbps to 1.5 mbps
    - Upstream: Usually around 128 kbps

                  “Dedicated” Bandwidth:
                  Doesn’t Change if More People
                  are Online
         How the Internet Works
               Cable Modem
 • Uses cable TV’s “coaxial” cable
               Asymmetrical
-Downstream: Speeds range from 512 kbps to 1.5
mbps
- Upstream: Usually around 128 kbps
                  “Shared” Bandwidth:
                 Goes Slower as More People are Online
                 - System Uses Equivalent of 1 TV Channel
                 “Down” and 1 TV Channel “Up”
                 - (1) 6 MHz television channel may support up
                 to 27 Mbps of downstream data
        How the Internet Works
           Speed Comparisons




• Everything
else is in the
BLUE shaded
area
How the Internet Works
   History of the World Wide Web
 Ted Nelson



                     • Nelson’s speech at Vassar, 1965
                     • Reported in Vassar College Newspaper
• First use of the term “hypertext”
• Vision owes much to Vannevar Bush
• Navigation through the information would be non-
linear, depending on each individual's choice of links.
This was more than text -- it was hypertext
•Nelson first used the term "Xanadu" to refer to his
hypertext vision in 1967.
    History of the World Wide Web
Tim Berners-Lee
                   • Physicist
                   • Worked at CERN in Switzerland
                          (Conseil Européen pour la Recherche Nucleaire)
                   • Today Called: European Particle Physics
                   Laboratory
 • 1989: Completed a project proposal for a system to
 communicate information among researchers
 • Researchers worked with diagrams (images)
 • Researchers worked different protocols (ftp, telnet,
 mail, etc.)
 • Envisioned a new way of thinking and a means to greater
 freedom and social growth than ever before possible
   History of the World Wide Web
              Tim Berners-Lee




• 1990: Invented term “World Wide Web”
• Invented protocol of the web (HTTP)
• Invented language of the web (HTML)
• Today: Director of the World Wide Web Consortium
     (The coordinating body for Web development)
                 http://www.w3.org/
 History of the World Wide Web
           First Browser - Mosaic
                              • U. of Illinois: NCSA
                              • Marc Andreessen
                              (Undergraduate Student)




          Mosaic 1.0
    (Released Nov 11, 1993)

• The first “graphical” browser
• 1993: Started a revolution
  History of the World Wide Web
        Second Browser - Netscape

            • Andreesen goes “corporate”

            • 1994: Marc Andreessen and colleagues
            leave NCSA to form "Mosaic
            Communications Corp" (now Netscape)

            • Founder of SGI, Jim Clark involved


• Andreesen netted $174 million by the age of 24
   History of the World Wide Web
 Dominant Browser – Internet Explorer

             • Microsoft
             • IE = About 90% of all browser usage

Bill Gates   • Netscape is down to about 8% - 10%
Founder
                 Other Browsers
               • Opera       • Mozilla
               • WebTV       • Mosaic

                 Browser Statistics
   http://www.upsdell.com/BrowserNews/stat.htm
   History of the World Wide Web
       Netscape Goes “Open Source”
• Netscape released the code
• Started an “Open Source Community” called
mozilla.org

• Netscape 6.0 and 7.0 are based on the work
of the “community”

• The “community” also created the browser
“Mozilla”
 The End



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