Web Services Ppt

Introduction to Web Services

Jane Hsu

Issues „ „ „

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What is a Web Service? Why are Web Services interesting? What e-commerce business models do Web Services enable? What security and privacy issues need to be addressed for Web Services to be successful? What are the platforms supporting web services? ‰ ‰

Microsoft’s .NET Platform Sun J2EE

Copyright (C) 2004 Jane Hsu

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The basic business proposition of web services… I want to be able to do business across the Internet with my customers, partners, and suppliers without having to know the intimate details of how they built their IT systems. „

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Applications, programming languages, operating systems and hardware are still needed to build the Web services and the software that invokes them. Process Automation, Workflow, Data transformation, and Systems management are required to deploy

Copyright (C) 2004 Jane Hsu

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Web as Powerful Archive

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Example: Yahoo! Stock Ticker „

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Vast databases of historical stock prices accessible at http://finance.yahoo.com Browser-oriented userfriendly displays Programs need to mimic users to request the information and then “scrape the screens” Inefficient and fragile Need a better mechanism!

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Copyright (C) 2004 Jane Hsu

Service Oriented Architecture

Bind

Service Requestors

Internet Find

Publish

Service Brokers Copyright (C) 2004 Jane Hsu

Service Providers

Legacy System 6

Loosely-Coupled Web Applications Web Services XM L/H

XM

TT P

T L/H

TP

P TT H L/ XM

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Interoperability Intra-business: „ EAI

Inter-business: „ B2Bi „ Supply chain management

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Software Design Principles „

Abstraction ‰ ‰

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Abstract & reuse useful functions in programs Abstraction hides implementation details

Componentization ‰

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Share code among programs by creating reusable software components Save time coding, debugging & testing Reusable components have value Components are local (i.e. live on your machine) 9

Copyright (C) 2004 Jane Hsu

Componentizing „

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To help different software applications communicate with one another Earlier development efforts ‰ ‰

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COM (Microsoft) CORBA (Sun/Java)

Web services are based on key standards ‰ ‰ ‰ ‰

Extensible Markup Language (XML) Simple Object Access Protocol (SOAP) Universal Description, Discovery and Integration (UDDI) Web Services Description Language (WSDL) Copyright (C) 2004 Jane Hsu

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Software Engineering Coverage Web Services Java RMI DCOM Message Oriented Middleware CORBA RPC DLL Subroutine Centralized Client-Server Distributed Objects Black box Standard interface Network standards 1970

1980

1991

1996

Web Services Open directory

1996

2000 11

Copyright (C) 2004 Jane Hsu

Distributed Component Technology CORBA

DCOM

Java RMI

SOAP

Communication

IIOP

RPC

IIOR or JRMP

HTTP

Message Format

CDR

NDR

Java Ser. Format

XML

Spec. Language

OMG IDL

IDL

Java

WSDL

Search Mechanism

Naming Service

Windows Registry

RMI Registry

UDDI

Copyright (C) 2004 Jane Hsu

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Web Services „ „

A web service is any software component that Is available over the Internet ‰ ‰ ‰

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“Programming the Web” “Remote procedure calls over the Web” Web sites with no user interface

Uses standard web messaging protocols (XML/SOAP) Is platform independent. i.e. Components are not tied to any one operating system or programming language. Enables highly distributed information systems 13

Copyright (C) 2004 Jane Hsu

Web Services vs. Web Applications Web Services

Web Application

Interface

program-program

human-program

Language

XML

HTML

Service Index

Search vis UDDI

Search via search engine

Application domain

B2B

B2C

Protocols

SOAP + HTTP/HTTPS/SMTP

HTTP/HTTPS

Copyright (C) 2004 Jane Hsu

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Features of Web Services „

Services as Components ‰

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Platform-Free ‰

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SOAP、UDDI、WSDL etc.

Dynamic Integration ‰

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Standards-based

Open Standards ‰

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reuse

On-demand Out-sourced

Interoperability Incremental Deployment Copyright (C) 2004 Jane Hsu

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Why will Web Services Succeed? Real Business Value is Delivered! „ „

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Allows for Applications on demand & “Utility-based” Computing ‰ Faster deployments, Lower skill levels, Faster ROI Based on real and open Standards with ubiquity ‰ TCP/IP, HTTP, XML, SOAP, WSDL ... ‰ Utilizes existing infrastructure We made the right choices this time ‰ Loose coupling, simple, business driven Early Industry Deployments ‰ Major Vendors totally committed (IBM, Microsoft, Sun, etc.) ‰ Customers already in production using web services ‰ Fastest Adoption rate of any technology in a long time Can cut cost of integration by up to 20% (McKinsey) -- the single biggest IT cost New business models & types of applications are possible Copyright (C) 2004 Jane Hsu

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Three Standards Based on XML „

UDDI (Universal Description Discovery and Integration) ‰ ‰

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WSDL (Web Service Description Language) ‰

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Yellow pages directory for services White/green pages Document describing the message exchange contract

SOAP (Simple Object Access Protocol) ‰

XML-based protocol for messaging 17

Copyright (C) 2004 Jane Hsu

Web Services Technology Stack Service Flow (WFMS)

XML (XML Schema, Namespace)

Management

Service Invocation & Messaging (SOAP)

Quality of Service

Service Description (WSDL)

Security (WS-Sec)

Service Discovery & Publication (UDDI)

Network (HTTP, SMTP, FTP) Copyright (C) 2004 Jane Hsu

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Evolution of UDDI „

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Goal: automated discovery and execution of ecommerce transactions Universal Business Registry (UBR) ‰ ‰ ‰

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White pages: company contact information Yellow pages: categorization/standard taxonomies Green pages: technical information about services exposed

Web service infrastructure UDDI.org is comprised of more than 200 major software developers and e-business leaders

Copyright (C) 2004 Jane Hsu

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White Pages „ „

Business Name Text Description ‰

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Contact info ‰

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list of multi-language text strings names, phone numbers, fax numbers, web sites…

Known Identifiers ‰

list of identifiers that a business may be known by – D-U-N-S (UDDI registry generated unique number for each business) Copyright (C) 2004 Jane Hsu

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Yellow Pages „

Business categories ‰

5 standard taxonomies in Version 2.0 „ „

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Industry: NAICS (Industry codes - US Govt.) Product/Services: Standard Industrial Classification, USPSC Location: Geographical taxonomy (GGC, ISOGT)

Implemented as name-value pairs to allow any valid taxonomy identifier to be attached to the business white page

Copyright (C) 2004 Jane Hsu

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Green Pages „

New set of information businesses use to describe how to “do e-commerce” with them ‰

Nested model „ „ „

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Business processes Service descriptions Binding information

Programming/platform/implementation independent Services can also be categorized

Copyright (C) 2004 Jane Hsu

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More Details „ „ „

UDDI SOAP WSDL

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BPEL: An Emerging Standard „ „

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Goal: specification for automating complex business processes. BPEL (Business Process Execution Language for Web services) will make it easier for businesses to create Web services applications that automate multi-step business processes, e.g. insurance claims The proposal was led by IBM, Microsoft, BEA Systems, and SAP. Submitted to the OASIS (Organization for the Advancement of Structured Information Standards) technical committee under royalty-free terms. Copyright (C) 2004 Jane Hsu

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Digital Trust Services Framework „ „ „ „ „

By VeriSign Authentication Authorization Transaction service, e.g. bill payment Security standards: ‰ ‰

XKMS (XML Key Management Specification) SAML (Security Assertions Markup Language)

Copyright (C) 2004 Jane Hsu

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The Web Programming Model „

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More loosely coupled that traditional distributed programming models like RPC, DCOM, and CORBA. Simple Web client-server interaction ‰ ‰ ‰

Exchange Messages that carry MIME-typed data Semantics of a message can be modified using headers The destination of a message is specified indirectly using a URL, and this level of indirection can be leveraged to implement load balancing, session tracking and other features

Copyright (C) 2004 Jane Hsu

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Architectural Characteristics of WS „ „ „ „

Distributed Loosely-coupled Standards-based Process-centric

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Promise of Web Service „ „

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CIOs surveyed by Basex Inc. 60% expect their Web services initiatives to be profitable within the next two years. 90% see it happening within the next five years. Jupiter Media Metrix survey of IT managers 50% see web services technology as a way to cut software integration costs. Copyright (C) 2004 Jane Hsu

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Web Services: The Trend „

A September survey of IT execs by Forrester Research reported that ‰

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85% of respondents planned to deploy Web services by 2004. Up from 71% a year ago.

IT managers see web services technology as a way to cut software integration costs. 29

Copyright (C) 2004 Jane Hsu

Web Services (In Practice) Find a Service

UDDI

http://www.uddi.org http://www.uddi.org Link to WSDL document

Web Service Consumer

How do we talk? (WSDL) http://yourservice.com /?WSDL http://yourservice.com/?WSDL XML with service descriptions

Web Service

Let me talk to you (SOAP) http://yourservice.com/svc1 XML/SOAP BODY Copyright (C) 2004 Jane Hsu Design-Time or Dynamic

Runtime

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Web Services Platforms „

Application Servers: ‰ ‰

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.NET J2EE ‰ ‰ ‰ ‰ ‰ ‰

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Provide tools for application development and Support efficient execution of applications

Microsoft

IBM Oracle Sun HP BEA Systems Sybase

WebSphere Oracle 9i Application Server Sun ONE (iPlanet) HP Web Service Platform, eSpeak WebLogic EAServer

Open Source: JBoss, JOnAS Copyright (C) 2004 Jane Hsu

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Web Services Supporters „ „ „ „ „ „

Microsoft .NET My Services IBM Sun HP BEA Systems Oracle

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Microsoft „

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Next year the software giant will release .Net My Services, an initiative formerly known as HailStorm that will deliver content, shopping, banking and other services over a variety of devices ranging from cell phones to PCs and handhelds. The massive operation will employ a global network of Web servers to house all manner of personal information, including e-mail accounts, address books, credit card numbers and photographs. On the infrastructure end, Microsoft is selling a family of e-business software for companies to create and run Web services, which include its forthcoming Visual Studio.Net development tools. Copyright (C) 2004 Jane Hsu

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IBM „

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Big Blue has built support for Web services into its WebSphere application-server software and offers Visual Age tools for building applications. WebSphere includes technology that runs transactions for Web sites and links to IBM's DB2 database software, which stores vast amounts of corporate and Web information, and its Tivoli Web services manager, which monitors performance of such products. IBM's Global Services arm is also said to be planning a move into the hosting end of Web services.

Copyright (C) 2004 Jane Hsu

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Sun „

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The company is building support for Web services standards SOAP, UDDI and WSDL into its iPlanet ebusiness software products, including its applicationserver software. By the end of 2002, Sun will add the existing Web services standards into Java 2 Enterprise Edition (J2EE), the Java standard for writing business software. The company says it will also release a tool for building Web services next year and is working on technology that will allow Java-based Web services to be compatible with Microsoft's .Net operations.

Copyright (C) 2004 Jane Hsu

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HP „

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The computing giant has the potential to be a major player, but it remains to be seen whether the hardware maker can make inroads into the software market. "HP and BEA are likely to have a significant play, and Sun's iPlanet is making some headway and will eventually catch up. HP has an edge because they had the idea before with E-speak," said analyst Mike Gilpin of Giga Information Group. Copyright (C) 2004 Jane Hsu

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BEA Systems „ „

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BEA was not as focused on Web services as IBM a few years ago. As the market leader in application-server infrastructure software, BEA is typically one of the quickest to get products out, and is expected to be highly competitive. BEA WebLogic Server won the 2002 Web Services Journal Editor's Choice Awards. ‰ ‰

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Best Web Services Application Server Best Middleware - BEA WebLogic

BEA's integrated development environment simplifies the creation of Web services for a broad range of developers. Copyright (C) 2004 Jane Hsu

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Oracle „

The database leader is moving in two directions on Web services. ‰

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First it is adding support for XML, SOAP, UDDI and WSDL to its 9i database-management software, application-server software and development tools so that its customers can use Web services in new systems. Second, it is developing Web-outfitted versions of its sales and customer relationship management software.

Oracle 9i Application Server Web Services Copyright (C) 2004 Jane Hsu

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Web Services: Promises vs. Reality Promises „ Can compose services „ Distributed „ Platform-independent „ Heterogeneous „ Can be discovered via UDDI registry „ All potentially developed and deployed independently

Reality „ Yes „ Yes „ Yes „ Yes „ ? „

?

Copyright (C) 2004 Jane Hsu

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Web Services Online Resources „

W3C Web Services Standards ‰

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SOAP document ‰

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http://ws.apache.org/axis/java/architecture-guide.html

WSDL document ‰

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http://www.w3.org/TR/2003/REC-soap12-part0-20030624/

AXIS document ‰

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http://www.w3c.org/2002/ws/

http://www.w3.org/TR/2003/WD-wsdl20-20031110

UDDI document ‰

http://uddi.org/pubs/uddi-v3.0.1-20031014.htm Copyright (C) 2004 Jane Hsu

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The Alphabet Soup of Web Services „ „

SOAP, UDDI, WSDL, XML GXA (Global XML Web Services Architecture) ‰ ‰ ‰

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WS-Security WS-Routing WS-Referral

WS-Policy WS-Addressing SDIG DIME (Direct Internet Message Encapsulation) SOA (Service Oriented Architecture) Copyright (C) 2004 Jane Hsu

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Midterm Report „

Pick a specific topic from the list ‰

Sign up at http://www.csie.ntu.edu.tw/~r92109/pmwiki/pmwiki.php/Main/PresentList

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Present it in class on March 14th, 2004 ‰

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Extra bonus ‰ ‰

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Submit your slides Install and demonstrate how it works Comparison of competing technologies/platforms

Maximum team size: 2 students Copyright (C) 2004 Jane Hsu

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