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Web Services

Web Services. It’s About Standards, Not Infinite Choices Barry Walsh . Thanks . To many, but especially these four valued colleagues Carl Jacobsen, U Del Bob Kvavik, U Minn Ed Lightfoot, UW Mark Olson, NACUBO Steve Relyea, UCSD. Today’s Overview. Emerging Technology – Web Services

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Web Services

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  1. Web Services It’s About Standards, Not Infinite Choices Barry Walsh

  2. Thanks • To many, but especially these four valued colleagues • Carl Jacobsen, U Del • Bob Kvavik, U Minn • Ed Lightfoot, UW • Mark Olson, NACUBO • Steve Relyea, UCSD

  3. Today’s Overview • Emerging Technology – Web Services • Standards…who needs them??? • Intra-institutional systems implications • Q & A

  4. Web Services Some of the following slides on Web Services borrow from the remarkable work in the current EDUCAUSE Review article on Web Services by Carl Jacobsen, University of Delaware, and are used with the express permission of the author and EDUCAUSE.

  5. Definitions • Web Services refers to an architecture that facilitates the interoperation of software through common protocols. IDC predicts that Web Services, which is still in its infancy, will grow from a $1.6 billion market in 2004 to $34 billion by 2007. Now we know why the big boys are singing from the same hymnal

  6. Web service • Definition: A Web service is a software application identified by a URI/URL, whose interfaces and binding are capable of being defined, described and discovered by XML artifacts and supports direct interactions with other software applications using XML based messages via internet-based protocols Web Services Architecture Requirements W3C Working Draft 29 April 2002 http://www.w3.org/TR/2002/WD-wsa-reqs-20020429

  7. Web Services • “Web services are a new breed of Web application. They are self-contained, self-describing, modular applications that can be published, located, and invoked across the Web. Web services perform functions, which can be anything from simple requests to complicated business processes… Once a Web service is deployed, other applications (and other Web services) can discover and invoke the deployed service.” “A Web Services Primer” quoted by Venu Vasudevan Senior Researcher, Motorola Labs www.xml.com - from IBM tutorial

  8. Web Services • “The promise of Web services lies in its ability to resolve the differences among shared, networked applications. Applications from different vendors, of various vintages, written in different languages, running on disparate platforms, easily communicate and cooperate, resolving their differences to act in concert.” Carl Jacobsen, University of Delaware EDUCAUSE Review March/April 2002

  9. What’s NOT a Web Service? • Standard web applications • Wrappered front ends to legacy systems Unless they have the WS attributes

  10. Web Services: THE ACRONYMS • XML • SOAP • UDDI • WSDL

  11. Web Services: THE ACRONYMS • XML – like HTML, XML is a “markup language” and the “x” stands for “extensible” • While HTML uses text tags to describe how the contents of a document will appear (tags for bold, header, underline, etc), XML uses text tags to describe how a document will be used (tags for invoice number, item number, price, grading format, etc.) • HTML is used to describe how a document will be displayed on a browser; XML describes how a document can be processed by a program, or application or system.

  12. Web Services: THE ACRONYMS • SOAP – stands for “Simple Object Access Protocol” and is just a messaging standard or protocol to allow Internet applications to communicate. • SOAP allows process control to be passed between two networked applications • It is not a language, nor a component, but a communications protocol that defines rules for disparate systems to interact.

  13. Web Services: THE ACRONYMS • UDDI – is the “white pages” and the “yellow pages” of Web Services. • Stands for “Universal Description Discovery and Integration” and is a Web directory that allows applications to announce its availability and services to other applications. • Web services registered in a UDDI directory may be “discovered” by other Web applications hunting for specific services, goods or partners.

  14. Web Services: THE ACRONYMS • WSDL – Web Services Description Language is an XML format used to describe the capabilities and interoperability required of a Web Service • WSDL provides an abstract definition of the communication details/rules between two applications, how a Web service will work with another application.

  15. Implementing the traditional way vs. using Web Services: http://www.webservicesarchitect.com/content/articles/apshankar02.asp?m49

  16. Web Services offers advantages • Capitalize on existing investments: • Portability: A Web Services solution is not only portable across platforms, it also facilitates cross technology integration. • Scalability: Web Services are highly scalable components, supporting industry strength scalability requirements. • Multiple client access: In addition to PCs-- palmtops, PDAs, cell phones etc. • Low costs: Web Services solutions may be cheaper to develop, maintain, and upgrade. http://www.webservicesarchitect.com/content/articles/apshankar02.asp?m49

  17. Why is the concept of web services important to us on campus? • External services • FSA • EBPP • Grant submission • Etc. • Internal development standards

  18. What’s the big deal about standards anyway? • Windows; Linux; Unix; MacOS, ES390 • Java, VStudio.Net, Cold Fusion, Lizardware • HP, Sun, IBM, Intel, ?? • Outlook, Lotus Notes, Groupwise • Client server, web, mainframe

  19. Let’s look at some other standards? • Electrical

  20. What if we let the electrical engineers decide what standards they wanted? • Voltage/Current: • Highest/lowest possible? • Frequency: • Highest?...motor speed? • Lowest?...circuit breakers

  21. What if the campus departments chose the voltage? • Physics would want 3 x 106 Volts

  22. What if the campus departments chose the voltage? • Math would want 3.1415926535897932 Volts

  23. What if the campus departments chose the voltage? • English department would want ?? Volts

  24. What if the campus departments chose the voltage? • Controller would want 34 or 35 Volts

  25. So what do we actually have? (in the US) • 115 v @ 60hz • Why? • We need a standard

  26. How do the engineers cope???? • Because it’s a standard!!!!

  27. “Web services won’t (in and of themselves) transform business. Business transforms business… Technologies only provide new opportunities; if enterprises are unwilling or unable to change their cultures and approaches to business, then very little transformation will occur.” Gartner Research Note: “What Web Services Will and Won’t Do” February 19, 2002 Web Services

  28. So What’s the Problem? • Institutional Vision • Portal based Service Delivery-one place! • Larry Faulkner at UT Austin has it • Stove piping • Functional • Technical • Provider-Centric view of Service Delivery

  29. Architecture Design Principles for a Proposed Higher Education Application • Design a highly functional and flexible financial information system and infrastructure by utilizing component-based design and development methodologies • Facilitate integration with existing university portals, enterprise applications and departmental systems • Select and utilize technologies that balance cost, vendor viability, support, functionality, and portability • Provide transactional document workflow and routing capabilities based on XML documents and technologies • Utilize web services to support application services and application integration.

  30. Technical Architecture Client Desktop 3rd Party Systems Internet Explorer / Netscape / Mozilla SOAP MS Windows, Macintosh OS/X Unix, Linux HTTP Web Server(s) Application Server(s) Apache Struts JDO log4j Apache HTTP Unix IP J2EE (Websphere) XML IP JDBC Unix SOAP Database Server(s) Oracle Unix JDBC

  31. Workflow Scenario • Workflow: aka routing and approval • In the following workflow scenario, the term ‘document’ refers to any electronic transaction designed to perform or complete some business process for the institution • Student requesting a drop/add approval • A purchase requisition • A hire event in HRMS • A transfer of funds in the fiscal system • A timesheet approval for student hourly • Etc. Hundreds of possible txns

  32. Scenario • Sample scenario describing workflow interaction with system: • ‘Document’ (transaction) is entered into the system • Routing instructions are created based on document type and additional input from user • Instructions are stored in associated XML document • System submits XML to route modules • Route modules scan XML for specific routing instructions and match to action request rules • Route modules return list of action requests for this document

  33. Scenario (cont’d) • System activates appropriate action requests by placing them on users’ action lists---in the portal!! • Users view the list of documents requiring their attention • User can view document in originating application, and can then perform an action on the document • If action is performed, the XML doc is updated with this info and sent back to the routing modules, where is then routed to the next destination • This continues until all routing is complete. • Every action along the way is logged for audit trail purposes

  34. Web Services • A powerful standard emerging in the Web world • Supported by all the major vendors • Enables loosely coupled business processes • Currently, the emphasis is on external partners such as FSA and others • Web Services model can accomplish the same objectives inside the academy • common application standards and protocols • Java or .Net • Significant downstream payoffs in system support and maintenance • Encourage creation of services that can be called as components • Enables the decentralization of application development without losing integration opportunities

  35. Questions ? Barry Walsh walsh@indiana.edu 812 855 6416

  36. Web Services: • Loosely coupled – “forgiving” interfaces rather than traditionally strict integration requirement of our legacy systems, including our “new” legacy systems • Self-describing and self-announcing: all specifications related to the use and behavior of a service are part of the service itself • Applications may invoke remote processes or applications as if they were a part of the invoking application • Specific technologies to: build, publish,and relate business and learning components across the network

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