e Commerce Technology 20 751 Lecture 5 Data

e. Commerce Technology 20 -751 Lecture 5: Data Interchange

Outline • The need for data interchange – Transactions imply data exchange • XML for identifying data – Separation of • content • appearance • document structure • Integrating with legacy applications – Legacy application: one you wish you could replace but can’t • ASN. 1 for self-describing data formats – Solves a different problem than XML does – Not what the data means but how it is encoded 20 -751 ECOMMERCE TECHNOLOGY SUMMER 2000 COPYRIGHT © 2000 MICHAEL I. SHAMOS

e. Commerce Data Exchange Needs RFQs Ship Notices Catalogs Letters of Credit Quotations Purchase Orders Electronic Payments Bills of Lading Invoices 20 -751 ECOMMERCE TECHNOLOGY SUMMER 2000 COPYRIGHT © 2000 MICHAEL I. SHAMOS

Invoice Example <Unit. Price>6. 05</Unit. Price> SOURCE: PROF. JEROME YEN 20 -751 ECOMMERCE TECHNOLOGY SUMMER 2000 COPYRIGHT © 2000 MICHAEL I. SHAMOS

Data Exchange Problem Different systems and applications use different names and formats for the same information: SOURCE: FTISOFT

How to Make Data Portable • Tell what the data means • Tell how the data is structured • Tell how it should look SO COMPUTERS CAN UNDERSTAND IT • BUT DO THESE SEPARATELY • • The meaning -- XML The structure -- DTD (document type definition) The formatting -- XSL (Extensible style sheet) Example: XML catalog structure

Content and Format Information conveyed in 2 ways: • words, pictures and other information (content) • visual clues font, font size and location (format) SOURCE: RACHEL SOKOLOWSKI 20 -751 ECOMMERCE TECHNOLOGY SUMMER 2000 COPYRIGHT © 2000 MICHAEL I. SHAMOS

XML Example <? XML version="1. 0" ? > <PRESCRIPTION> <MEDNAME MED="Amoxil"> Prescribed medication: Amoxil</MEDNAME> <FORM TYPE="capsule"> Form: capsule </FORM> <DOSAGE AMOUNT="25 mg"> Dosage: 25 mg</DOSAGE> <RXINSTRUCTIONS FREQUENCY="daily"> daily </RXINSTRUCTIONS> </PRESCRIPTION> SOURCE: RACHEL SOKOLOWSKI 20 -751 ECOMMERCE TECHNOLOGY SUMMER 2000 COPYRIGHT © 2000 MICHAEL I. SHAMOS

XML at a glance Well Formed Document: <Book> <Author>George Soros</Author> <Title>The Crisis of Global Capitalism</Title> <Year>1998</Year> <Publ>Public Affairs</Publ> <Price>26. 00</Price> <ISBN>1 -891620 -27 -4</ISBN> </Book> DTD: Document Type Definition <? xml version="1. 0"> <!DOCTYPE Book [ <!ELEMENT Book (Author, Title, Year, Publ, Price, ISBN)> ]> SOURCE: PROF. JEROME YEN 20 -751 ECOMMERCE TECHNOLOGY SUMMER 2000 COPYRIGHT © 2000 MICHAEL I. SHAMOS

XML Recipe Example <? xml version="1. 0"? > <Recipe> <Name>Apple Pie</Name> <Ingredients> <Ingredient> <Qty unit=pint>1</Qty> <Item>milk</Item> </Ingredient> <Qty unit=each>10</Qty> <Item>apples</Item> </Ingredients> <Instructions> <Step>Peel the apples</Step> <Step>Pour the milk into a 10 -inch saucepan</Step> <!-- And so on. . . --> </Instructions> </Recipe>

Document Is Now Block-Structured <? xml version="1. 0"? > <Recipe> <Name>Apple Pie</Name> <Ingredients> <Ingredient> <Qty unit=pint>1</Qty> <Item>milk</Item> </Ingredient> <Qty unit=each>10</Qty> <Item>apples</Item> </Ingredients> <Instructions> <Step>Peel the apples</Step> <Step>Pour the milk into a 10 -inch saucepan</Step> <!-- And so on. . . --> </Instructions> </Recipe>

DTD (Document Type Definition) XML is extensible because it allows user-defined tags DEFINES TAG Recipe HAVING A Name AND 3 OPTIONALTAGS XML COMMENT <!-- Sample DTD --> <!ELEMENT Recipe (Name, Description? , Ingredients? , TAGS Name, Description Instructions? )> CONTAIN ONLY <!ELEMENT Name (#PCDATA)> CHARACTER DATA <!ELEMENT Description (#PCDATA)> TAG Ingredients CONTAINS ZERO OR <!ELEMENT Ingredients (Ingredient)*> MORE Ingredient TAGS <!ELEMENT Ingredient (Qty, Item)> Ingredient TAG HAS A <!ELEMENT Qty (#PCDATA)> Qty TAG FOLLOWED <!ATTLIST Qty unit CDATA #REQUIRED> BY AN Item TAG <!ELEMENT Item (#PCDATA)> TAG Qty HAS TWO <!ATTLIST Item optional CDATA "0" POSSIBLE ATTRIBUTES: optional (DEFAULT VALUE 0) is. Vegetarian CDATA "true"> is. Vegetarian (DEFAULT true) <!ELEMENT Instructions (Step)+> SOURCE: JAVAWORLD TAG Instructions HAS ONE OR MORE Step TAGS

Document Object Model (DOM) in XML • An XML structured document can be treated and manipulated as an object • DOM parser transforms the document into a parse tree • Program can walk the tree, performing arbitrary transformations • DOM API then converts the new tree to another XML file • New file can be printed, sent over the net or used as input to another program • Applications can now exchange data without knowing formats — DTD contains everything necessary SOURCE: JAVAWORLD

XML Financial Implementations • OFX - Open Financial Exchange – Fields • FIXML - XML grammar for FIX (Financial Information Exchange). MSDW is a principal. More information • FINXML - Capital markets. Info. Vendor: Integral • SWIFT • X 12 - data exchange standard for business transactions SOURCE: PROF. JEROME YEN 20 -751 ECOMMERCE TECHNOLOGY SUMMER 2000 COPYRIGHT © 2000 MICHAEL I. SHAMOS

XML Implementations • HL 7 - health information (Health Level 7) • EDIFACT/Simpl. EDI - syntax - repository • IFX - Interactive Financial Exchange formerly OFX/Gold (Open Financial Exchange ) - personal banking. • Rosetta. Net - catalogues, supply chain automation • OTP - Open Trading Protocol - buying and payments • Financial markup standards • XML-enabled product vendor list • ECML - Electronic Commerce Markup Language – Field names 20 -751 ECOMMERCE TECHNOLOGY SOURCE: PROF. JEROME YEN SUMMER 2000 COPYRIGHT © 2000 MICHAEL I. SHAMOS

Ubiquitous XML Architecture SOURCE: PROF. JEROME YEN 20 -751 ECOMMERCE TECHNOLOGY SUMMER 2000 COPYRIGHT © 2000 MICHAEL I. SHAMOS

Impact of XML • • • Interchange mechanism between applications Rapidly becoming the database language of the Web XML client/server transactions over http: Permits web data repositories XML properties: – Scalable – Maintainable – Easy to use (spreadsheet style skills) – Interoperable (exchange business components) 20 -751 ECOMMERCE TECHNOLOGY SUMMER 2000 COPYRIGHT © 2000 MICHAEL I. SHAMOS

Connecting to Legacy Systems by “Wrapping” “WRAPPER” Web Server Web App 20 -751 ECOMMERCE TECHNOLOGY MAINFRAME Wrapper Middleware SUMMER 2000 Legacy App COPYRIGHT © 2000 MICHAEL I. SHAMOS

Connecting to Legacy Systems The “screen scraper” HTML data Terminal screen data Screen scraper Client Legacy system (mainframe) Existing application Legacy database Web server SOURCE: WIM GEVERS 20 -751 ECOMMERCE TECHNOLOGY SUMMER 2000 COPYRIGHT © 2000 MICHAEL I. SHAMOS

Standard Encodings • Business systems must exchange data in different formats: – Invoices, payment orders, checks, bills of lading, delivery instructions, authentication information • Need standard notation to describe transmitted data in communication protocols • BUT: what format is the data in? – What does 437573746 F 6 D 6572 (hex) mean? – Where do fields begin and end? – How about complex data structures (arrays, etc, )?

Need for Standard Encodings • Interoperability – How can my program read your program’s data? • Parties cannot always agree in advance on standards • Encodings need to be changed – YYMMDD became YYYYMMDD (the Y 2 K problem) • Minimize programmer and development time

Abstract Syntax Notation (ASN) • ASN. 1 is a method of encoding data so that the format can be decoded from the data itself • ASN. 1 is not a programming language • It describes only data structures. No code, no logic.

Abstract Syntax Notation • ASN. 1 has primitive types: BOOLEAN, INTEGER, REAL, ENUMERATED, BIT STRING, OCTET STRING, IA 5 STRING, . . . • ASN. 1 has – SET (unordered) SEQUENCE (fixed order) of primitive types – CHOICE for selecting alternative types (integer or real) • Can define new types: Month : : = INTEGER (1. . 12) Day : : = INTEGER (1. . 31) Daily-stock-volume : : = SEQUENCE SIZE (31) OF INTEGER

Basic Encoding Rules (BER) • Define how fields described in ASN. 1 should be encoded • Units of BER are data elements • A data element is a triple: { identifier-type, length, value } • Some type codes: BOOLEAN IA 5 STRING INTEGER SEQUENCE SET 01 16 02 10 31 (8 -BIT ASCII) • The string “Customer” would be encoded as 16 08 43 75 73 74 6 F 6 D 65 72 IA 5 STRING LENGTH 8 20 -751 ECOMMERCE TECHNOLOGY HEX “C” HEX “r” HEX “u” SUMMER 2000 COPYRIGHT © 2000 MICHAEL I. SHAMOS

Basic Encoding Rules • Content field may be primitive (value) or structured (content has subcomponents) 20 -751 ECOMMERCE TECHNOLOGY SUMMER 2000 COPYRIGHT © 2000 MICHAEL I. SHAMOS

Basic Encoding Rules • Content field may be primitive (value) or structured (content has subcomponents) Person : : = SET { name IA 5 String, age INTEGER female BOOLEAN }. BER encoding (in hex) of the instance {“Maggie”, 4, TRUE}: SET 31 0 E LENGTH OF CONTENT (BYTES) 16 06 CODE FOR IA 5 STRING 20 -751 ECOMMERCE TECHNOLOGY M a g g i e 4 D 41 E 7 69 65 LENGTH OF “Maggie” DATA 02 CODE FOR I NTEGER SUMMER 2000 01 LENGTH OF INTEGER 4 04 01 CODE FOR BOOLEAN TRUE 01 FF LENGTH OF BOOLEAN COPYRIGHT © 2000 MICHAEL I. SHAMOS

Using ASN. 1/BER ASN. 1 DEFINITIONS ASN. 1 COMPILER SOURCE LANGUAGE (JAVA, C) DATA STRUCTURES ENCODER/ DECODER APPLICATION CODE APPLICATION PROGRAM (JAVA, C) COMPILER APPLICATION PROGRAM NOW READS AND WRITES DATA ACCORDING TO BER 20 -751 ECOMMERCE TECHNOLOGY SUMMER 2000 APPLICATION PROGRAM COPYRIGHT © 2000 MICHAEL I. SHAMOS

Applications of ASN. 1 • • • Automatic Identification and Data Capture Air traffic control Telephone communications Electronic payment protocols (e. g. SET) Digital certificates Manufacturing message specification (MMS) for controlling manufacturing devices 20 -751 ECOMMERCE TECHNOLOGY SUMMER 2000 COPYRIGHT © 2000 MICHAEL I. SHAMOS

Automatic Identification and Data Capture (AIDC) • Problem: how to obtain data from physical objects – Examples: product ID, price, serial number • Bar code two-dimensional • • Magnetic stripe card RFID CIRCUIT Smart card Radio Frequency Identification (RFID) Real-Time Locating Systems (RTLS) TAG WAND READER 20 -751 ECOMMERCE TECHNOLOGY SUMMER 2000 COPYRIGHT © 2000 MICHAEL I. SHAMOS

AIDC Applications • • Highway toll collection Freight containers Animal identification Theft detection Inventory, asset management Traffic control Gas station billing SOURCE: TSS 20 -751 ECOMMERCE TECHNOLOGY SUMMER 2000 COPYRIGHT © 2000 MICHAEL I. SHAMOS

AIDC Applications • • • Highway toll collection Freight containers Animal identification Inventory, asset management Traffic control 20 -751 ECOMMERCE TECHNOLOGY SUMMER 2000 COPYRIGHT © 2000 MICHAEL I. SHAMOS

Q&A 20 -751 ECOMMERCE TECHNOLOGY SUMMER 2000 COPYRIGHT © 2000 MICHAEL I. SHAMOS