Web Technology

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Web Technology

• http//www.csie.ncnu.edu.tw/hychen/web_tech
• Herng-Yow Chen (???)
• Multimedia and Communication Laboratory
  (?????????)
• Dept. of Computer Science and Information
  Engineering
• National Chinan University, Taiwan
• email hychen_at_csie.ncnu.edu.twphone 049-2910960
  ext 4843

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Agenda

• Administrations
• Reference books, papers, and web sites
• Homework and grade
• Coverage
• Software component (client, proxy, server)
• Quick review of computer network
• Web protocols (HTTP)
• Evaluating web performance
• Web caching and multimedia streaming
• Research perspectives

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Coverage

• Web Architecture
• HTTP protocols
• Web documents (HTML, SGML, XML, etc)
• Search Technology on Web
• Performance Turing of Web
• Multimedia over Web
• Web applications
• Paper reading, report writing, project
  implementation, and technical presentation

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What we wont cover definitely

• Web software usage
• Homepage design and tool usage
• Web programming details
• Java, Java applet, Java servlet
• JavaScript, VB script and Dynamic HTML controls
• Server-side script (e.g, PHP and ASP
• Plug-Ins and ActiveX
• how to connect to database (e.g., MS-SQL, mySQL)
• Any programming skills you should pick up on your
  own for your final project.

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Textbook and Reference books

• TextbookHTTP, The definitive guide, OReilly
  2002Lecture notes (.ppt, require MS-powerpoint)
• References
• Web Protocols and Practice, 2001
• Web Server Technologies, 1996
• Wildes WWW technical foundations of the world
  wide web, 1999
• Web site optimization, 1997
• Capacity planning for web performance metrics,
  models, methods, 1998
• Computer network and Internet, 1999

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Supplementary Papers

• Find Papers
• IEEE Xplore (http//www.ieee.org)
• ACM digital library (http//www.acm.org)
• Selected Papers (.pdf, require acrobat reader)
• IEEE Internet Computing magazine
• IEEE Communications magazine
• IEEE Multimedia magazine
• ACM Communications magazine
• Communication of the ACM
• Web-related conferences or journals

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Web resources

• My pages
• http//www.csie.ncnu.edu.tw/hychen/web_tech
• Others
• W3C, the World Wide Web Consortium,
• http//www.w3.org
• IETF, the Internet Engineering Task Force
• http//www.ietf.org
• Apache software foundation, http//www.apache.org
• others

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Grade

• No examination!
• Report, Project, and Presentation (90)
• Assignments 30,
• Midterm- oral report 30,
• Final exam- project presentation 30
• Class participation 10
• Good answering to questions in discussion class
• Good report (presentation) in English
• Good class attitude (without skipping class)

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Class Format

• Classes are divided into two forms.
• Topic Presentation
• 1 period
• Students or TAs will be assigned to help this
  part.
• Lecture
• 2 periods

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Question 1 Expectations

• Topics that you want me to cover or discuss in
  this course?
• Any other expectations?

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Question 2 Web Basics

• Who invented Web?
• Have you heard MOSAC or Lynx before? Whats that?
• Whats the different between HTTP and TCP?

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Rules of Homework

• Turn in your report in class.
• E-mail an electronic copy to me before deadline.
• Deadline 1200 p.m. Sunday
• Email subject web-tech, homework, student-id
• Attached document format ms-word (.doc) or
  acrobat (.pdf)
• Make all your reports accessible through
• http//www.ncnu.edu.tw/youraccount/web_tech

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Making Presentation

• Present reading assignment (sometimes in class).
• Final Presentation (in final exam. week)
• Format
• powerpoint format or web-compliant format
• Presenters who speak in English will be rewarded
  a 10 bonus grade.

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Question and Problem

• Find me
• Office R401, technology building III
• Phone ext. 4843
• Email hychen_at_csie.ncnu.edu.tw
• Lab. Multimedia communication lab (R407)
• Phone ext. 4864

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Overview of Web Architecture and its related
Technologies

• Period 6 hours at most.
• Homework 1 paper report at least.
• Reference book 1. Web protocol and practice.

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Web software components

• Web client
• Web server
• Web Proxy
• Others
• DNS server
• search engine (spiders or robots)
• multimedia streaming server

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Web components (fig.)
DNS Server
Web Server
Web Client
Proxy Server
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Semantic Components of the Web

• Uniform Resource Identifier (URI)
• popular term URL
• Hypertext Markup Language (HTML)
• derived from SGML
• Hypertext Transfer Protocol (HTTP)
• a request-response protocol

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Standardization

• Internet Engineering Task Force (IETF)
• an open community contributing to the evolution
  of the Internet (http//www.ietf.org)
• publications Request for Comments (RFCs)
• the first RFCs was published in 1969
• World Wide Web Consortium (W3C)
• was founded in 1994 (http//www.w3c.org)
• has developed a variety of standards, called
  Recommendation, related to the web.
• tend to focus on the representation of Web
  content
• such as HTML, CSS, XML, MathML, SMIL, etc.

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Web protocol HTTP

• Internet protocol (IP)
• Transmission Control protocol (TCP)
• Domain Name System (DNS)
• DNS-based Web server load balancing
• Other issues
• Application-layer protocols
• telnet, FTP, SMTP, NNTP, etc.

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Layering of Protocol
Application layer
Transport layer
Network layer
Link layer
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Layering of Protocol
Application layer
Transport layer
Network layer
Link layer
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Protocols involved in transferring HTTP messages
HTTP messages
TCP segments
Datagrams
Datagrams
Datagrams
Ethernet
Ethernet
ATM link
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HTTP 1.0 and HTTP/1.1

• Overview of HTTP
• RFC 1945 and RFC 2616
• HTTP extensibility
• Security
• HTTPS using SSL in Web exchanges
• Security in HTTP/1.0

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Web Traffic and Performance

• Overview for web traffic measurements
• monitoring the web transfers
• generating the measurement records
• preprocessing the data in preparation for
  analysis
• Performance Turing

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Web applications

• Information retrieval and search engine
• Multimedia streaming
• Real Time Streaming Protocol (RTSP)
• which borrows several key concept from HTTP/1.1

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Quick reviews on Internetworking

• Period 6 hours at most.
• Homework 1 paper report at least.
• Reference book Computer Network and Internet,
  comer

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Computer Network and Internet

• PART 1 Data transmission
• PART 2 Packet Transmissions
• PART 3 Internetworking
• PART 4 Network applications

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PART 1 Data transmission

• Transmission media
• Copper wires, glass fibers, radio, satellite,
  microwave, infrared, laser, etc.
• Local Asynchronous Communication (RS232)
• Using electric current to send bits
• Standard for short-distance communication
• Baud rate, Framing, and errors.
• Device mouse, connected to modem
• Long-distance transmission (Modulation)
• Modulation scheme (FM, AM, etc.)
• Time Division Multiplexing

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PART II Packet Transmission

• Packet and error detection
• Parity bit checking, checksum, CRC code
• Local Area Network (LAN) technologies and network
  topology
• Ethernet (bus), Token ring (ring)
• Hardware addressing and identification
• LAN wiring and LAN extension
• Repeater, bridge, switches
• Wide Area Network (WAN) technologies and routing
• Protocols and layering

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PART III. Internetworking

• Internet Protocol (IP) address
• Classes of IP Addresses, special IP address
• Binding Protocol address (ARP)
• IP datagrams and its forwarding
• IP encapsulations, fragmentation, and reassembly
• The Future IP (IPv6)
• Error Reporting Mechanism (ICMP)
• TCP reliable transport service

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PART IV Network Applications

• Client-Server Interaction, the socket interface
  and programming
• Domain Name System (DNS)
• Electronic mail system, file transfer, and remote
  file access
• World Wide Web pages and browsing
• Web Programming CGI, Java.
• Network Security

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Hypertext Transfer Transfer Protocol (HTTP)

• Period 6 hours at most.
• Homework 1 paper report at least.
• Reference book