Technology for e-Commerce Overview XML

Fall 2000C.Watters2 Outline Introduction History and Overview Show me the Code! Applications Protocols Conclusions

Fall 2000C.Watters3 Introduction What is XML? eXtensible Markup Language Related to both SGML and HTML “XML is like HTML with the training wheels off” -Dan Connolly, leader of XML activity at W3C

Fall 2000C.Watters4 XML Uses tags to identify semantics of data looks like HTML, but isn’t Introduction Carolyn Watters XML this and that is license free, platform-independent and well-supported

Fall 2000C.Watters5 SGML-HTML-XML?? The great ancestor of markup languages SGML (Standardized General Markup Language) Grammar is implemented using data Grammar is defined by a Data Type Definition (DTD) XML & HTML are cousins!

Fall 2000C.Watters6 Statistics Canada Welcome to Stats Canada Statistics Canada …….. We like numbers….. What we do Census Special surveys a href=“online.html”>Online data

Fall 2000C.Watters7 HTML HTML - Advantages Simple - fixed set of tags Portable - used with all browsers Linking - within and to external documents HTML - Disadvantages Limited tag set Can’t separate the definition from content Can’t define structure of contents

Fall 2000C.Watters8 XML XML allows anyone to define a document structure separate from its display structure Explicit Definition - DTD

Fall 2000C.Watters9 Some Code Schema Entity –Passport Details SubEntities –Last Name –First Name –Address Entity –Address SubEntities –Street –City –Town –State –Province –……..

Fall 2000C.Watters10 DTD

Fall 2000C.Watters11 Internal DTD and Instance <!DOCTYPE passport_details [ <!ELEMENT address (street,(city|town),(state|province),(ZIP|postal_code),country,contact_no?, *)> ]> Smith Jo Stephen 1 Great Street GreatCity GreatState 1234 GreatLand

Fall 2000C.Watters12 Shared DTD XML Document specifies the DTD Smith Jo Stephen 1 Great Street GreatCity GreatState 1234 GreatLand

Fall 2000C.Watters13 XML into HTML Need to convert XML tags into appropriate HTML tags for use in a browser!! Smith

Fall 2000C.Watters14 CSS and XSL CSS - Cascading Style Sheets –can predefined HTML display (font etc) –these are shared and reused XSL - XML Style language –predefine display characteristics for XML entities –transform into CSS for browsers to use

Fall 2000C.Watters15 Cascading Style Sheets CSS last_name { font-family: verdana, arial; font-size: 15pt; font-weight:bold; display: block; margin-bottom: 5pt; } first_name { font-family: verdana, arial; font-size: 15pt; font-weight:bold; display: block; margin-bottom: 5pt; } street, city, town, state, province, ZIP, postal_code { font-family: verdana, arial; font-size: 12pt; font-weight:bold; color:green; display:block; margin-bottom: 20pt; margin-top: 40pt; } { font-family: verdana, arial; font-size: 12pt; font-weight:bold; color:blue; display:block; margin-top: 5pt; }

Fall 2000C.Watters16 <xsl:stylesheet xmlns:xsl=" xmlns=" result-ns=""> Address XSL (Style Language)

Fall 2000C.Watters17 Coordinating Heterogenous Databases Separation of Structure / Content / Display Document Validity Checking Potential Use in Standards Importance of XML

Fall 2000C.Watters18 Example Boeing Boeing places a DTD on its site part purchasers use this DTD Boeing can use multiple XSL stylesheets

Fall 2000C.Watters19 Boeing (cont’d) customer creates an order document, they can verify the validity of that document against the DTD. this ensures they are transmitting only type- valid orders. in turn, Boeing can ensure they are receiving only type-valid documents.

Fall 2000C.Watters20 Examples of Evolving Industry XML Standards XML/EDI Open Financial Exchange (OFE) Open Trade Protocol (OTP) HL7 (Health Level 7) Kona Proposal Resource Description Format (RDF) Industry-wide DTDs

Fall 2000C.Watters21 A unified specification for the electronic exchange of financial data between financial institutions, businesses and consumers via the Internet. Supports consumer and small business banking, bill payment, bill presentment and investments, including stocks, bonds, and mutual funds. Open Financial Exchange

Fall 2000C.Watters22 Global Standard for all forms of trade on the Internet Provides consistent consumer purchasing experience regardless of the payment instrument or software and hardware product used. Specifies how Internet transactions can occur, independent of the method of payment Open Trade Protocol

Fall 2000C.Watters23 Differs from Secure Electronic Transaction (SET). OTP complements, but does not replace other protocols. Provides consumers with a record of purchases for tax purposes, make expense claims, etc. Provides the same factual transaction for the virtual world. Open Trading Protocol

Fall 2000C.Watters24 <!DOCTYPE Transaction [ <!ELEMENT Payment (CredCardPay / OtherPay), Amount, Payer, Payee) <!ELEMENT CredCardPay (Cardtype, CardNo, Expdate, CardHolder) <!ELEMENT OtherPay ANY <!ELEMENT Amount (CredCardPay / OtherPay), Amount, Payer, Payee) <!ELEMENT Payer ( , (Name)?, Address)?) OTP DTD

Fall 2000C.Watters25 In the major Web Browser products. In Microsoft Office In every major database tool by end of In every HTML tool by end of CommerceNet believes that XML may just be the “killer application” needed to open up the Worldwide Web for Electronic Commerce. Is this for real?

Fall 2000C.Watters26 XML - Advantages Platform and system independent User-defined tags Doesn’t require explicit DTD Display format and content are separate XML - Disadvantages Requires a processing application “Pickier” than HTML Must be converted to HTML to view in browser Summary

Fall 2000C.Watters27 W3 Consortium: kazillions of XML books in every bookstore! Resources