Internet Essentials

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Internet Essentials

• Today
• Introduction of the course
• Introduction to the internet
• Lecturers
• Yong Yue
• Fiaz Hussain
• Marc Conrad
• Email marc.conrad_at_luton.ac.uk
• Room D104 (Park Square).

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Aims Objectives

• To provide a broad understanding of the Internet,
  its essential components and the relationship
  which exists between them.
• To allow for the construction of basic, but
  professional, web-sites using industry standard
  software tools.
• To provide an understanding and awareness of the
  major protocols used within an Internet
  environment.
• To develop an appreciation of the issues (such as
  security) relating to the construction of
  web-sites.

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In-Course Assessment (50)

• The first assessment will be a group project
  consisting of the design development,
  demonstration, and documentation of a web-site,
  based on a given scenario. Students will be
  expected to form groups of 4 or 5 in the first
  three weeks of the semester. Though the
  assessment is completed through group work, it is
  expected that every student is knowledgeable in
  all development aspects of the project and an
  appropriate peer group assessment will take place
  to reflect individual contribution.
• Handout date Week 5
• Hand-in date Week 11

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Exam (50)

• The second assessment will be a centrally
  invigilated examination covering mainly the
  material presented in the lecture, as well as the
  practical sessions.

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References

• Internet World Wide Web How to Program,
  Deitel, Deitel Neito, Prentice-Hall, 2000.
• Essential Dreamweaver 4.0 fast Rapid Web
  Development, Fiaz Hussain, Springer 2002.
• http//w3schools.com

See also bookshops/WWW for Web design,
HTML/XML, protocols internet security.
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Teaching Schedule

• Week 1 Introduction
• Week 2 3 Dreamweaver
• Week 4 The WWW
• Week 5 Web browsers search engines
• Week 6 Web design management
• Week 7,8,9 HTML, XML, CSS
• Week 10 Protocols Internet Security
• Week 11 Assignment 1 Presentations
• Week 12 Revision Group
• Week 13 Revision Individual

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Teaching Resources

• The slides of the lectures can be found on
• J drive
• Blackboard
• http//www.perisic.com/luton/XCT02

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Ah the data, at last a space for the reason we
are going through all this nonsense.(Jon
Postel in IEN 2, the defining document of TCP/IP)
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Introduction to the Internet

• How does it work?
• Is this a good design?
• Is this the Internet?

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Information is exchanged through a network
SERVER
University of Luton
Amazon
CLIENT
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What is the Internet?

• Not World Wide Web (WWW)
• Global network of computer networks
• Universal medium
• - publishing
• - distribution
• - real-time communications
• - broadcasting
• Try List five day-to-day Internet applications

The WWW is only one aspect of the Internet
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Internet Applications

• Day-to-day Internet applications include
• electronic mail (e-mail)
• information browsing
• down/up loading of files
• electronic transactions (e-commerce)
• distance learning
• low-cost Internet telephony
• video-conferencing
• radio broadcasting
• Web Tv (television broadcasting)

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Internet Protocols

• Comprises many protocols
• What is a protocol?
• format used to transmit and to receive data
• typically consists of four components
• - an information field for data
• - the destination address
• - originating address
• - error detection and correction codes
• Single unit is used to hold the four components
  together
• Single unit packet, cell or frame
• IP networks packets
• Packets assembled at source and sent across
  various
• paths to their destination

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A short history of Internet protocols
Acronyms RFC Request for Comments IEN
Internet Engineering Notes TCP Transmission
Control Protocol IP Internet Protocol FTP File
Transfer Protocol SMTP Simple Mail Transfer
Protocol POP3 Post Office Protocol, Version
3 HTTP Hypertext Transfer Protocol

• 1974 TCP RFC 675
• 1977 TCP/IP IEN 2
• 1980 Telnet RFC 764
• 1980 FTP RFC 765
• 1982 SMTP RFC 821
• 1983 Usenet RFC 850
• 1993 Gopher RFC 1436
• 1993 POP3 RFC 1460
• 1996 HTTP/1.0 RFC 1945
• 1997 HTTP/1.1 RFC 2068

• Try Write at least one sentence about each of
  the above protocols (search the Internet for the
  RFC numbers).

Useless informations RFC 1 1969 RFC 3595
09/2003 RFC 3 defines RFC
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Internet

• TCP/IP
• Transmission Control Protocol/Internet Protocol
• TCP manages the packets, sequencing and error
  
• control
• IP
• manages the addressing
• each machine has a unique IP address
• library.luton.ac.uk 194.80.215.212
• Stateless as each client request is considered
  new
• and unrelated to previous one
• HTTP
• Files can contain references to other files,
  whose
• selection will result in additional transfer
  requests

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Understanding a Web address

• http//www.perisic.com/marc/hello.html

means
Use the http protocol to retrieve the file with
the name hello.html that is located in the marc
folder on the machine www.perisic.com
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Understanding a Web address

• Example http//www.perisic.com/marc/hello.html

Use the http protocol to retrieve the file with
the name hello.html that is located in the marc
folder on the machine www.perisic.com
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Web addresses
Use the http protocol to retrieve the file with
the name hello.html that is located in the marc
folder on the machine www.perisic.com

• Example http//www.perisic.com/marc/hello.html

• http is now the mostly used protocol, other
  protocols are
• ftp Sometimes used for the transmission of
  software, program files (files you save on the
  disk).
• https Secure transmission of html files.

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Web addresses
Use the http protocol to retrieve the file with
the name hello.html that is located in the marc
folder on the machine www.perisic.com

• Example http//www.perisic.com/marc/hello.html

• www.perisic.com is an alias for the computer
  where the data is located.
• A nameserver matches the domain name to a real
  machine.
• Each top level domain (.com, .net, .uk, .edu,
  .hr, .de, .tv, .ac, .info, ) has it own rules
  for the other levels.

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Web addresses
Use the http protocol to retrieve the file with
the name hello.html that is located in the marc
folder on the machine www.perisic.com

• Example http//www.perisic.com/marc/hello.html

• Usually the files on a web server are ordered in
  a hierarchy of folders, similar to the folders on
  your local machine.
• A folder can have subfolders, subsubfolders,
  etcExample
• http//news.bbc.co.uk/sport1/hi/golf/calendar/defa
  ult.stm

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Web addresses
Use the http protocol to retrieve the file with
the name hello.html that is located in the marc
folder on the machine www.perisic.com

• Example http//www.perisic.com/marc/hello.html

• hello.html is the name of the file that is
  retrieved from the machine.
• The extension .html means that the Hypertext
  Markup Language is used to encode this file.

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Summary

• The internet is not homogenous, or centrally
  organised.
• The internet is a global network of computers.
• Usually, one computer can identified as the
  server, and another one as the client when a
  specific task is performed.
• Information between the server and the client is
  interchanged via protocols. Protocols are
  organised in layers. The most important ones are
• TCP/IP (lowest layer protocol)
• HTTP (highest layer protocol)
• A web address defines the location of a document
  and the protocol used for retrieving this
  document.