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<?xml everywhere?>. ''XML could turn the Web into one giant database for translating information wending through disparate computer systems. XML could be the new Rosettastone.'' Anthony J. Blake, vice-president AT&T Labs in Menlo Park, Calif. David L. Mainz. AGENDA. XML Explosion
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<?xml everywhere?> ''XML could turn the Web into one giant database for translating information wending through disparate computer systems. XML could be the new Rosettastone.'' Anthony J. Blake, vice-president AT&T Labs in Menlo Park, Calif David L. Mainz
AGENDA XML Explosion All about XML SessionOne (90 minutes) Break (30 minutes) Session Two (40 minutes) XML in the trenches XML in your business Question & Answer (20 minutes)
Purpose Assumptions • Heard the hype; read the trade journals • Executive or Manager Perspective • Wondering how XML can benefit your company • Goals • A concise intro to XML for perspective • Give a general idea where and how XML is used and some examples of implementations • Give understanding of benefits and risks of XML
XML Explosion • Proliferation of XML-based Technologies • XML Routers and Accelerators • XML Databases and RDB Support • Application Platforms: .NET, J2EE • Web Services • XML-based Languages: ebXML, VoiceXM • XML Tools: Parsers, DOMs, Editors • W3C Central Focus • XML Books, Websites, Online Communities • Companies delivering XML products, services • IDC (research firm): By 2006, XML servers grow to over $3 bln market, tools to $400 MM
What is <?XML?> • eXtensible Markup Language • Markup Language-method of conveying metadata—information about a dataset • Extensible—provides a standard mechanism for extending itself – create your own tags, structures • Text document that is self-describing, self-delimiting data using a set of HTML-like tags
XML Document Prolog Processing Instructions Document Element Properly Nested Child Elements Element Attributes CDATA Sections Empty tag <?xml version="1.0"?> <!– comments here <?xml-stylesheet type="text/xsl" href="style2.xsl"?> <WDTWEATHER> <HEAD> <DATE>N/A</DATE> <PLACE> <CITY>Farmington</CITY> <STATE>Michigan</STATE> </PLACE> </HEAD> <CURRENT> <TEMP units="F">67F</TEMP> <WEATHER>Sunny</WEATHER> <RH units="percent">50</RH> <WIND>10 MPH</WIND> </CURRENT> <PERIOD01> <![CDATA[ Whatever ]]> <PERIOD01 /> </WDTWEATHER>
Birth of a Meta-language • Based on Standard Generalized Markup Language • SGML adopted in 1986 as data and exchange standard by the ISO • SGML is powerful and extensible but considered too complex • Started in 1996 by the W3C, XML was designed to have the simplicity and mass appeal of HTML (also based on SGML) but with the power of extensibility • Current specification is XML 1.0 Recommendation (1998) with XML 1.1 advanced Candidate Recommendation earlier this month • W3C: XML is the universal format for structured documents and data on the Web
XML shall be straightforward to use over the Internet XML shall support a wide variety of applications XML shall be compatible with SGML It shall be easy to write programs which process XML documents The number of optional features in XML is to be held to an absolute minimum, ideally zero Goals of XML
XML documents should be human-legible and reasonably clear The XML design should be prepared quickly The design of XML shall be formal and concise XML documents shall be easy to create Terseness in XML markup is of minimal importance Goals of XML
Namespaces Disambiguate vocabularies Application Program Interfaces Document Object Model (DOM) Tree-based Simple API for XML (SAX) Event-based XML Schema or DTD Describes structure and constraints of data Extensible Style Language (XSL) Specifies transformation and presentation of content XML Query Language (XQuery) Query and retrieving XML elements XLink, XPointer, XPath Advanced linkage or navigation to other nodes SOAP, UDDI Remote procedure calls XML Is a Family of Specifications
DTD/Schema • Communicating your document structure • Distinguishes Valid from Well-formed • Document Type Definition • Formally and precisely delineates structure: vocabulary, elements, attributes, relationships • DTDs fall short in providing rigorous structure declarations, such as data typing and namespace mixing, necessary for automated processing. Solution: Schema
Advantages of XML • Standards-based and Open • Portable and Interoperable • Platform, Application, Vendor Neutral • Increases Reliability as user agents automate processing of documents • Saves training and development costs by having a singe format with many uses • Robust, Inexpensive, Optimized Toolset • Reuse of data/multiple formats • Human Readable • Web Enabled
XML Concerns • Steep learning curve for tools and related technologies like XSL; not really simple • Developers must code own processing applications; learn new tools, languages • No standardization on schemas or tags—some industry fracture • Immaturity of products, standards, and security • XML is verbose: high storage, bandwidth, cpu cost • Acronym proliferation: XML, XSL, XHTML • Is XML another IT fad???
XML Security • XML not designed with security in mind • Need to secure documents (or portions) and exchange thereof • XML enc: encryption of data and tags or selected parts of document using keys • XML-Signatures: similar to security certificate to ensure no tampering • XKMS: XML Key Management Spec –register and distribute keys used by XML-Sig • XACML – eXtensible Access Control ML – used to control access to documents • SAML – Security Assertion ML – authentication process
General Application Classes • Extension (new language, vocabularies) • Exchange (A2A, B2B, B2G) • Transformation and Processing
Commerce & Industry • BPML: Business Process Markup Language • Web Services: Fortune 1000 Aggressively adopting web services– FactPoint Group and Outsource Research Consulting • Amazon.com web service allows searching on author, title, publisher, etc., and returns results in XML • Ebay Price Watcher web service • Fedex Package Tracker • Supply Chain: Major retail chains like Wal-Mart are working on standards for synchronization between trading partners based on XML
Government • US OMB publishes Business Reference Model for its Federal Enterprise Architecture – XML document that describes federal business areas, functions, lines of business. Designed to facilitate efforts to transform govt to be more citizen-centered, results-oriented, market-based • IRS XML Developers Forum for Employment Tax E-File System- provides info to develop applications for E-file • Edgar Online promulgates eXtensible Business Reporting Language for companies to distribute financial reports in a portable way eGovernment Initiatives
Science & Education • edXML – focuses on complex PK12 requirements– standards setting for best practices • MathML – describes mathematical notation structure and content • Molecular Dynamics ML (MODL)- chemical simulations • NeuroML – describes models and networks of neurons • eXtensible Scientific Interchange Language – transport language for scientific data objects • Turing Machine Markup Language – describes Turing machines • RiboML – used for ribosomal science
Semantic Web • WWW designed for simplicity, not information management • Vision of the next generation network • Content publishers provide notation to categorize content • Autonomous agents use that notation to gather, filter, organize desired information • Resource Description Framework (XML language) • Long way off; Fraught with many difficulties: complexity, spam, proper categorization
XML in the Trenches How are XML solutions implemented? • Design or acquire XML document/schema/DTD • XML Editors, Schema generator • XML Parsers (SAX, Forward Only, In-Memory) • XML DOM / DOM object • XPATH • XSL/T • Biztalk, Web services
XML in Your Business What are your questions? • Should I be using XML? Where? What tools should I be using? Where do I start? Why are you asking? • Become an XML expert (or find one) • Start small and proceed incrementally • Understand your data • Do you have data you exchange with outside partners, branches, or departments • Do you have partners already using XML • Do you need to support multiple views or devices • Can you find inefficiencies in your organization that could be addressed by XML
Sources • Martin, Didier, et al., Professional XML. Wrox Press. • Richards, Russ. Information Briefing to the ANSI XML Forum, Oct. 11, 2001. • WWW Consortium (W3C) • Doll, Shelley. XML Security Who’s Who. Builder.com.
Links • www.w3c.org/xml • www.xml.org • www.xml.com • www.xmlmag.com • msdn.microsoft.com • www.perfectxml.com • www.topxml.com • xml.coverpages.org Question & Answer (20 minutes)
Break (15 Minutes) Next Up • x • x