2008-13-en - naist...cgm is note as central character of web2.0 – difference factor that compare...

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Information Network 1　-13- 1 Information Network 1　-13- 2

 Review the web service  Recent trends of Web  Why web become widely used?


  Late 1980’s –  Concept of “Engineering Workstation”

•  1M workstation (1 MIPS, 1MB memory, 1M pixel display) •  UNIX system + Ethernet

–  Research & Education environment •  “Campus Network” •  University’s (undergraduate) students use campus network

environment, but what can the university provide that system? •  Evolution of “Information service”

–  Pilot services •  “Gopher” for directory services

–  Client / server model –  Hierarchical menu navigation & multimedia (text & images)

•  “WAIS” for digital library –  Client server –  Z39.50 protocol (ISO std.) for information retrieval

Information Network 1　-13- 5

 World Wide Web –  Late 1980’s, CERN –  Client / Server model –  Sharing research information over the Internet

•  Technical / research articles shared over the internet •  Mechanism for “annotation” •  Text only system, but structured document “hyper text”

–  Initial engine implemented in early 1990’s, •  Servers, clients by CERN and other groups •  University of Illinois's “NCSA Mozaic” •  Multimedia hypertext

–  mid 1990’s: standardization process –  Around year 2K: industrialize much on many countries


The Internet

client server

Web browser Web server

GET uri

Server response

Mime document

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The Internet

client server


GET uri

Server response

Mime document

cgi-bin

CGI (common gateway interface) • program execution in the server side • execution result is replied as a MIME document

generate


The Internet

client server


GET uri

Server response

Mime document

Helper application • program execution in the client side • program that process the MIME document form server • There are also integrated into browser (plug-in).

interpretation・processing


The Internet

client server


POST data

Server response


 Uniform Resource Identifier –  RFC 3986 “Uniform Resource Identifier (URI): Generic

Syntax”

 Hyper Text Markup Language (HTML) –  RFC1866, HTML version 2.0 → HTML 4.01 (W3C doc.) –  XHTML 1.1 (W3C doc.) –  HTML is a media type of MIME framework

•  RFC2045, “Multipurpose Internet Mail Extensions (MIME), Part One: Format of Internet Message Bodies”

 Hyper Text Transfer Protocol (HTTP) –  RFC1945, HTTP v1 –  RFC2616, HTTP v1.1bis


scheme://authority/path?query#fragment

 scheme: access procedure for the server （protocol）  authority: user@host:port  path: path for resource access (hierarchical

structure)  query: used for resource access of nonhierarchical

structure  fragment: this information is evaluated after the

resource access . For example, the paragraph number of page is specified by this information.

http://www.naist.jp/japanese/ippan/daigaku_annai/daigaku.html Information Network 1　-13- 12

 Multilingualization –  contents expression by MIME –  enable by contents expression –  text that plural languages are mixed is resolved by Unicode

 Multimedia-compatible –  handling of various data by utilization of image, voice and

helper –  recently, there are beautiful contents that use video and

flash.  Data transmission from users

–  File uploader, blog, CGM, web2.0  Integration with another applications

–  data base etc –  feasible technology in the Web server side –  CGI-BIN work effectively

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Touch Panel PC Windows or Linux Arcade Mode　(Web browser)

Utilization of closed IP network

service is provided by web server

Backend system

  There is PC that has touch panel interface   Utilization of Web browser arcade mode

–  in this mode, menu bar and window title are hided   increasing the case that ATM constructed by Web browser

–  reduction of development period, ease of contents replace –  is able to brake out of the specified embedded system → does not need

special engineers


  Web services are provided by Web server that associated with embedded system

–  http server on Vxworks, Linux, T-engine, etc. –  there are many embedded system that has a network interface

  using web for system management –  decrease development cost of user interface –  lead to dramatic improvement in maintenance performance

Network Equipment: Cisco, Juniper Networks…

Embedded Device: Web Camera, Sensor Node…

Home Electric Appliances: HDD Recorder


 Movie/Image –  YouTube is typical example


 Fusion with a map information – Google maps


 Digital library replaces the function of old library –  IEEE Digital Library is well-know

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 Various systems are developed as a Webware –  Cybozu is well-known group ware that based on Web –  account processing,　group ware, E-mail, asset

management, room management, schedule management, etc.



 There is no information service platform which has great success. –  E-mail ?

•  E-mail exists as a network service that is used by everyone •  mailing list and an announcement service exists •  E-mail is weak than web when looked at e-mail from scalability

and technology concentration

 Why did the Web develop into only this well? –  It may be that we understand the secret of development of

application in the internet –  this is important for leaning about an application


  First step in academic area –  1990 Web developed for information sharing in high-energy

physics area by CERN –  Mosaic that is developed by NCSA cleared the way for utilization of

multimedia contents.   Standardize Process

–  IETF & W3C

  Industry excited –  1990’s　many technologies have thought in relationship with Web –  browser war between Microsoft Internet Explorer and Netscape

Navigator –  The Strategy by Adobe –  etc


Technology Development Engineering Deployment

Standardization “De Facto”

Regulations Marketing strategies

No demarcation


Technology Development Engineering Deployment

Standardization “De Facto”

Regulations Marketing strategies

No demarcation

CERN & NCSA IETF

W3C

Open Source Community

Industries

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 HTTP = General Purpose Data Transmission Protocol –  Request / response type transmission –  transmission data has the MIME

The Internet

client server

http server Web browser (helper)

HTTP


 MIME Type –  is format for multilingualization and multimedia of E-mail –  MIME type is defined for data that use in the internet

•  various language and application data can use in E-mail by MIME type

 In principle, information that expressed by MIME type can transmit in HTTP protocol –  even if File format is anything, http can transmit the

information that MIME type is defined –  freedom of information that is used in HTTP is improved by

the appearance of the helper application


 Most of the internet services are read-only –  Most of users does not complain when change the method

of information update. –  note that we cannot say so in the Web 2.0 era

 Most service is idempotent –  it was able to apply a large scale of the service


 a few servers for many clients

The Internet

Contents uploader

contents supplier • access by another method and route　

Idempotent Process • 　load balancer • 　cluster •  valid for load balance and fault management

side effect process • 　process aggregation • 　target : DB etc


 HTTP protocol needed the preservation at an early date –  technology about encrypted communication is integrated –  https : SSL, TLS, etc. –  Basic functions

•  encrypted communication •  peer authentication

 Various profits –  preserve login information and credit information –  preserve all accesses for the server –  Recently, there is no wonder that utilization of SSL/TLS


Client Server

server certificate (X.509), public key (server)

cipher set, compression type, session ID

server certificate

generates pre-master key by random number generator

encryption by server public key

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Client Server

secrete key

start encrypted communication

server key client key server key client key


 Simple operation  only use static link

 Description of HTML is easy  Coordinate dynamic behaviors to cgi-bin  Web interface is the button and input field

In the end, creator and user can use easily


  Server is MIME translator   Implementation of the HTTP structure is easy   In client side, if contents are limited, implementation is very easy

and compact   simple html processing is very easy

–  Style sheet and XHTML processing are difficult  Cgi-bin implementation is very easy  Multifunctional products are provided for the market

  constructs the environment that is provided the impractical performance in embedded system,

  Even OSS is a commercial product, but correspondence is possible in both


 Server and client are developed by many enterprises. But, Many elements (HTTP, MIME, etc.) are standardized by IETF –  does not need to get the license from specified enterprise –  provided open source software for specified implementation. All industry were able to refer to these resources. –  protocols are standardized in IETF and W3C that have open

environment –  industry had open mind

•  e.g. Adobe, Microsoft, etc


 Most information is expressed by text, image and movie –  Now, many blogs provides image and movie contents. –  Flash contents are high cost contents by business base （in

my opinion）

 1990’s technology –  Mosaic has supported image since about 1994 –  Real Networks etc have supported movie since about 1996


 Another success factors exists  What kind of factors exists?

–  technical elements –  market elements –  compatibility with social system –  etc.

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 Customer Generated Media  Service use various contents that is provided from

users  CGM is note as central character of Web2.0

–  difference factor that compare Web2.0 and another network service is the information sharing in general public and data that is provided by user side manages in the server side.

–  requires the methodology different from Blog  SNS (Social Network System) is one form of CGM

–  utilization of environment information that is generated by members

–  but, it’s my guess that SNS is service that relate to CGM

 Enormous Blogs (blogspot, ameblo.jp, ….)  SNS (mixi, linkedin, facebook, gree, …)  Video hosting service (YouTube, Nicovideo, ….）  Map information（postmap.org, Google maps, ….）  Word of mouth site (kakaku.com, tabelog, …)  Q&A Site (hatena, goo, ….)  COI (Community Of Interest) site (関心空間 http://

www.kanshin.com/)  ….


 Server manages data. Client processes the information that independent from the model.

 In this side, –  typical environment is Google tools –  Gmail, Google document, Google Calendar, …..

 This technology needs enormous computer –  needs new business model –  In the future, advertise income model become weak

•  In Y! and Google, advertisement is a base of income


 Google Document  Google Calendar


 Sophisticated application is processed by the helper application –  Adobe flash –  Java script & program –  platform that generate dynamic contents

 Helper application is external processing unit when looked at from web browser. Therefore helper application denies that application implements to web browser. –  In this situation, how do you recognize new contents? –  How to embed to system?

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 Security –  Security is our first priority, but how? –  Scalability on server configuration –  Realtime applications can be supported by this web

architecture? –  Web 2.0 movement –  Retro fit problem if we have an old application sever, say

developed in year 2000 –  ……


 How does this web world improve?

 What kind of role does the user have? –  What is the thing at the end of world that customer

generated “something”? –  battle about originality and credibility is started

 What kind of research will be possible? –  Can research pass the business? –  Maybe Google has the research achievement.


 We focus on the Web  Web is the infrastructure that widely use in around

the world  But, we must solve many problems of Web.

–  Web is important as a research theme –  Web has many problems

 Pros & Cons  Web is interesting as a subject

 Which web services do you think advanced? Choice two web services and write your answers of them with reasons in perspective of engineering .


2008-13-en - naist...cgm is note as central character of web2.0 – difference factor that compare...

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