Скачать презентацию Web Services The Next Dimension of Enterprise Computing Скачать презентацию Web Services The Next Dimension of Enterprise Computing

35b0da7063cd74eb40b751446bd9a796.ppt

  • Количество слайдов: 38

Web Services The Next Dimension of Enterprise Computing Dr. Billy B. L. Lim School Web Services The Next Dimension of Enterprise Computing Dr. Billy B. L. Lim School of Information Technology Illinois State University

Outline n Web Services ¡ ¡ ¡ What Why How Who When Not Outline n Web Services ¡ ¡ ¡ What Why How Who When Not

Questions n Assuming that you’re a venture capitalist: ¡ n Would you fund a Questions n Assuming that you’re a venture capitalist: ¡ n Would you fund a company that proposes to build xyz. Books. com and compete directly with the Amazon. com’s of the world? Assuming that you’re a IT 168/177 student: ¡ Would you be able to write an app that gather user addresses and plot a map that shows the route from ISU to the closest address?

E-Commerce Scenarios n n Objective: Capitalize on the success of e-commerce and build a E-Commerce Scenarios n n Objective: Capitalize on the success of e-commerce and build a web site to sell books, CDs, and others Scenario 1 ¡ ¡ Build Billy. Books. com and compete directly with the Amazon. com’s of the world Any chance of success here?

E-Commerce Scenarios n Scenario 2 Source: Atkin, J. , “Amazon Everywhere, ” PC Magazine, E-Commerce Scenarios n Scenario 2 Source: Atkin, J. , “Amazon Everywhere, ” PC Magazine, 9/2003.

What are Web Services? n W 3 C 2003: ¡ “A Web service is What are Web Services? n W 3 C 2003: ¡ “A Web service is a software system designed to support interoperable machine-to-machine interaction over a network. It has an interface described in a machine-processable format (specifically WSDL). Other systems interact with the Web service in a manner prescribed by its description using SOAP-messages, typically conveyed using HTTP with an XML serialization in conjunction with other Web-related standards. ”

Why Web Services? Observations n “I couldn’t make DCOM work. I tried and failed, Why Web Services? Observations n “I couldn’t make DCOM work. I tried and failed, again and again. But I can make a Web service in a heartbeat. ” -- Jim Gray, Microsoft Distinguished Engineer (Turing Award (~= Nobel Price for computing) Winner)

Explosive Growth of API Calls / WS n Reference: http: //www. slideshare. net/jmusser/open-apis-state-of-themarket-2011 Explosive Growth of API Calls / WS n Reference: http: //www. slideshare. net/jmusser/open-apis-state-of-themarket-2011

Why Web Services? Observations n Projected Revenues ¡ 380 millions in 2001 vs. 15. Why Web Services? Observations n Projected Revenues ¡ 380 millions in 2001 vs. 15. 5 billions in 2005 (Source: Zap. Think, Inc. ’ 02) ¡ IDC estimate: 1. 6 billions in 2004 vs. 34 billions in 2007 (Source: South China Morning Post, May 28, ’ 02)

Why Web Services? Observations n “When do you expect your company to develop a Why Web Services? Observations n “When do you expect your company to develop a Web Services strategy? ” Source: Info. World Web Services Survey, July ‘ 01

Why Web Services? Observations www. ws-i. org n The industry is aligned … ¡ Why Web Services? Observations www. ws-i. org n The industry is aligned … ¡ ¡ Broad industry initiative for Web services n Over 150 industry leaders Interoperability across platforms, applications, and languages

Why Web Services? Observations Why Web Services? Observations

Why Web Services? Observations n Technology of the Year (Info. World ’ 02) Why Web Services? Observations n Technology of the Year (Info. World ’ 02)

Why Web Services? n n Interoperable Easy to use Reusable Ubiquitous Why Web Services? n n Interoperable Easy to use Reusable Ubiquitous

1 st Generation Web Applications UI Logic Biz Logic Browsers OS Services Source: Gusmano 1 st Generation Web Applications UI Logic Biz Logic Browsers OS Services Source: Gusmano ‘ 02 Servers Data, Hosts

2 nd Generation Web Applications Rich Client UI Logic Richer Browsers Biz Logic Tier 2 nd Generation Web Applications Rich Client UI Logic Richer Browsers Biz Logic Tier OS Services Source: Gusmano ‘ 02 Servers Data, Hosts

Next Generation Web Applications Other Services Smarter Clients Applications Become Programmable Web Services XM Next Generation Web Applications Other Services Smarter Clients Applications Become Programmable Web Services XM L XML Standard Browsers HTML Smarter Devices XM L Biz Logic & Tier. Web Logic Service OS OS Services ML X Public Web Services XML Foundation Services XML Internal Web Services XML Open Internet Communications Protocols (HTTP, SMTP, XML, SOAP) Servers Data, Hosts Source: Gusmano ‘ 02

Web Services: Life Cycle Service Registry (e. g. , IBM UDDI service) publish service Web Services: Life Cycle Service Registry (e. g. , IBM UDDI service) publish service (e. g. , stock quote) Service Provider (e. g. , Brokerage House) find service bind to service Service Requester (e. g. , XYZ Financial Software) Life Cycle of a Web Service Execution (Registry, Lookup, and Consumption)

What is Under the Hood? n n XML SOAP WSDL UDDI What is Under the Hood? n n XML SOAP WSDL UDDI

Web Services: SOAP, WSDL, UDDI Web Services: SOAP, WSDL, UDDI

An Overview of SOAP n n Simple Object Access Protocol Lightweight XML-based messaging format An Overview of SOAP n n Simple Object Access Protocol Lightweight XML-based messaging format Builds on ¡ W 3 C XML standards ¡ IETF HTTP standard Works with: ¡ ¡ ¡ Any operating system Any programming language Any platform

What is a SOAP Message? SOAP Message The complete SOAP Message Protocol Headers Standard What is a SOAP Message? SOAP Message The complete SOAP Message Protocol Headers Standard Protocol (HTTP, SMTP, etc. ) and SOAP Headers SOAP Envelope encloses payload SOAP Headers SOAP Body Message Name & Data

encloses headers Individual headers contains SOAP Message Name and Data XML Encoded SOAP Message Name and Data

Simple SOAP Request (Using HTTP) POST /Stock. Quote HTTP/1. 1 Host: www. stockquoteserver. com Simple SOAP Request (Using HTTP) POST /Stock. Quote HTTP/1. 1 Host: www. stockquoteserver. com Content-Type: text/xml Content-Length: 323 SOAPAction: “www. stockquoteserver. com/Get. Last. Trade. Price” DIS

Simple SOAP Response (Using HTTP) HTTP/1. 1 200 OK Content-Type: text/xml; charset=utf-8 Content-Length: nnnn Simple SOAP Response (Using HTTP) HTTP/1. 1 200 OK Content-Type: text/xml; charset=utf-8 Content-Length: nnnn 24. 5

WSDL n n Web Services Description Language Lets Web Services describe ¡ ¡ ¡ WSDL n n Web Services Description Language Lets Web Services describe ¡ ¡ ¡ what they are where they can be found how they should be used

" src="https://present5.com/presentation/35b0da7063cd74eb40b751446bd9a796/image-29.jpg" alt="Simplified WSDL example " /> Simplified WSDL example

Complete one: ISU Hello in Foreign Language Translator

UDDI n n Universal Description, Discovery, and Integration Lets companies find publicly available Web UDDI n n Universal Description, Discovery, and Integration Lets companies find publicly available Web Services on the Internet or corporate Intranets.

UDDI UDDI

How useful are Web Services? n Web services: Some possibilities ¡ ¡ ¡ ¡ How useful are Web Services? n Web services: Some possibilities ¡ ¡ ¡ ¡ Financial information (e. g. , stock quotes) Sports information Weather information News Delivery status Tax and shipping calculations Any data that is relevant to the client

Web Services: Who? n Who is doing this? ¡ Vendors n n ¡ Users/Consumers Web Services: Who? n Who is doing this? ¡ Vendors n n ¡ Users/Consumers n n n Microsoft, IBM, Sun, Oracle, HP, BEA, etc. . NET passport, Calendar, Alerts, Amazon Web Services, etc. Nordstrom, General Motors, etc. List of public Web Services http: //www. xmethods. net/ Who should pay attention to this? ¡ All of us!

Web Services: When? Web Services: When?

Web Services: When? n Web Services will enter most organizations in three distinct phases: Web Services: When? n Web Services will enter most organizations in three distinct phases: [Source: IDC] ¡ 2002 (within the firewall) n n ¡ 2004 (contained external users) n n n ¡ Simplified app integration Increased developer productivity Simplified business-partner connectivity Richer app functionality Subscription-based services 2006 to 2008 (fully dynamic search and use) n n Casual / ad-hoc use of services New business models possible Commoditization of software Pervasive use in nontraditional devices

Web Services: The Not? n Challenges/Issues ¡ ¡ ¡ ¡ Reliability / Consistency Security Web Services: The Not? n Challenges/Issues ¡ ¡ ¡ ¡ Reliability / Consistency Security Authentication Privacy Billing Reuse Performance Incompatible implementations of standards

Web Services: “Lingua Franca” Source: Clarke ‘ 02 Web Services: “Lingua Franca” Source: Clarke ‘ 02

References n n n Clarke, N. , “. Net & the J 2 EE: References n n n Clarke, N. , “. Net & the J 2 EE: Web Services - Can we live together? , ” Java. One 2002. Gosling, J. , Next-Generation Web Services Conference, Keynote address, Jan, 2002. Gusmano, M. , “Build Web Services with VB. NET, ” Microsoft Internet Developer Group, April 2001.