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Escaping the Legacy Jungle. XML and Web Services in Digital Government. Today’s Speakers. Dave McComb, Semantic Arts Sanjeev Batta, Coraxis Corporation Todd Shelton, Netdesk Corporation Rick Cook and Paul Piper, TAAG, Web Services Subcommittee. Agenda.
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Escaping the Legacy Jungle XML and Web Services in Digital Government
Today’s Speakers • Dave McComb, Semantic Arts • Sanjeev Batta, Coraxis Corporation • Todd Shelton, Netdesk Corporation • Rick Cook and Paul Piper, TAAG, Web Services Subcommittee
Agenda • Dave McComb: Web Services and Legacy Apps: A Marriage of Convenience? • Sanjeev Batta: Service Oriented Architecture • Todd Shelton: Getting to Web Services • Rick Cook and Paul Piper: Web Services TAAG
Web Services and Legacy Apps:A Marriage of Convenience? Dave McComb Semantic Arts, Inc www.semanticarts.com (970) 490-2224
Three responses • What’s one more string? • Cutting the Gordian Knot/ Starting over • Untangling the mess, a bit at a time
Frustration • Being a systems person these days is frustrating • Everything takes many times longer than we know it could, because we have to deal with the spiderweb of existing interconnections
Before we get to the answer • How did we get in this situation? • Mostly through a series of ad hoc decisions about what things mean, and how systems should communicate • How do we get out? • This will require some leadership above the project level to determine the language systems should use to talk to each other • It requires renegotiating new agreements between systems • This presentation is about…
Hope • New technology • New approaches • New methods and with hope comes…
Buzzwords • XML • Message Oriented Middleware • Web Services
The Distinctionary • Is: a glossary • Is distinct from other glossaries: structurally each definition first specifies what the more general type of thing the word is, and then provides a way to distinguish this thing from others that are similar.
XML • Is: a markup language <person> Dave McComb </person>
XML • Is distinct from other markup languages: by allowing tags that at least have some hope of being Semantic html for instance <H1> Dave McComb </H1> <H1> Fido </H1>
What makes XML interesting and potentially useful for us • Preserves context and structure • Document/ Message duality • Potential for application to application communication But for the most compelling factor in XML’s future success…
The Final Jeopardy Answer 4’ 8 ½”
What is the distance between North American standard gauge RR tracks, and a good analogy for the reason for XML’s coming ubiquity?
MOM (Message Oriented Middleware) • Is: Infrastructure Software • Is distinct from other infrastructure software: in that it allows you to send messages between applications without necessarily knowing the identity or location of the other application, and without necessarily waiting for a response.
Other Interesting Things About MOM • Promotes asynchronicity • Promotes loose coupling • Allows broadcast of messages & multiple use of messages • Opens up many avenues for redundancy and parallel conversions
Web Service • Is: A way to invoke functionality remotely • Is distinct from other ways to invoke functionality remotely: in that it allows you to express the calling arguments in XML over the internet.
Other Interesting Things About Web Services • Exposing your API as XML • Unaffected by many changes to invoking message • SOAP allows inter-machine calls, even through firewalls • Easy to set up and use
Web Service“show me” • Normally, there is nothing to show • It’s systems integration, when it works you don’t see it • Mostly behind the firewall • But here is a pretty public example
“If Amazon were as easy to use as Google” www.mockerybird.com
I type my search into mockerybird’s site, they then call amazon through their web service
Mockerybird then reformats the returned results. I then add one of these books to my “list”
Zoom in on “Your List” my selected item immediately shows up… I click checkout
I get a summary, and some options, including buying from Amazon
I’m at amazon’s site now (new window) and the book I selected from Mockerybird is right in with my other amazon selections!
Two ways to think about web services • From the consumers standpoint • And from the producers standpoint
Web Services, from the providers standpoint • You have a value added service, you’d like to make it available to the widest possible audience • You might want to charge for this privilege • Maybe something as simple as reporting air quality at a certain location, or most recent outbreaks of west nile virus. • Maybe it’s supplying 9 digit zip codes for addresses.
Web services from the consumers standpoint • What additional information would you like to make available at the point of consumption? • What additional services would you like to make available?
EAI, Portals and Composite App • There are three main points of consumption for Web Services: • EAI • Portals • Composite Apps
Finding and Negotiation with a Web Service UDDI WSDL SOAP
Some Example Web Service(very fine grained) • Calculation • Currency Conversion • Email validation
Some Example Web Service(medium grained) • Immigration status • Language Translation (gist) • Issue Line of Credit • Immunization Requirement for Travel to Foreign country
Some Example Web Services (coarse grained) • Outbound Correspondence • Imaging • Accounts Receivable • Auditing • Abstracting
Some Example Web Services (very coarse grained) • Contact management • Payroll
Strategies for taking advantage of this trend • Message Enable your legacy systems • Publish Services that will add value and help you at the same time (ZIP +4) • Implement Portals and Composite Apps with • Internal Services, and • Optional external services
Untangling Gulliver XML Message Bus Web Service or other Adapters
Compelling reason to get on the Web Services Bandwagon • Freedom – from the legacy bonds of confinement • Economics – it’s far cheaper to build systems this way • Looking good – this will be the measure of eGov success in the future • Not looking bad – avoid having to explain why you can’t do this
Thank you If you have questions, or would like additional copies of this material, feel free to contact me: Dave McComb Semantic Arts (970) 490-2224
Service Oriented Architecture Sanjeev Batta Coraxis Corporation Sanjeev@coraxis.com
Industry Projections • IBM • “Web Services will be bigger than Java or XML” – Rod Smith, VP of Emerging Technology, IBM • Forrester Research • By 2003, the market for software components used to build services will represent a $14.5 billion industry. • Gartner Group • Within the next 4 years, 60% of all new business applications will utilize a service-oriented architecture • By 2004, 40% of financial services transactions and 35% of online government services will be web service-based