eCommerce Technology 20-751 Data Interchange

20-751 ECOMMERCE TECHNOLOGY

SUMMER 2002

COPYRIGHT © 2002 MICHAEL I. SHAMOS

eCommerce Technology20-751

Data Interchange


SUMMER 2002


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


SUMMER 2002


eCommerce Data Exchange Needs

Ship Notices

Bills of Lading Electronic Payments

Purchase Orders

Invoices

RFQs Catalogs Quotations

Letters of Credit


SUMMER 2002


Invoice Example

<UnitPrice>6.05</UnitPrice>SOURCE: PROF. JEROME YEN


SUMMER 2002


Data Exchange Problem

Real NameApplication 1Field Name

Application 2Field Name



Customer Customer_name Cust_name Account Cust

Customer number Customer_num Cust_num Account_num Client_number

Quantity Quantity Par_amount Trade_Quantity Shares

SOURCE: FTISOFT

Different systems and applications use differentnames and formats for the same information:


SUMMER 2002


How to Make Data Portable

• Tell what the data means• Tell how the data is structured• Tell how it should look

• BUT DO THESE SEPARATELY. MIXING IS BAD

• The meaning -- XML• The structure -- DTD (document type definition)• The formatting -- XSL (Extensible style sheet)• Example: XML catalog structure

– DTD, XSL

SO COMPUTERS CANUNDERSTAND IT


SUMMER 2002


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


SUMMER 2002


XML Recipe Example

<?xml version="1.0"?><Recipe>

<Name>Apple Pie</Name><Ingredients>

<Ingredient><Qty unit=pint>1</Qty><Item>milk</Item>

</Ingredient><Ingredient>

<Qty unit=each>10</Qty><Item>apples</Item>

</Ingredient></Ingredients><Instructions>

<Step>Peel the apples</Step><Step>Pour the milk into a 10-inch saucepan</Step>

</Instructions></Recipe>


SUMMER 2002


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><Ingredient>

<Qty unit=each>10</Qty><Item>apples</Item>

</Ingredient></Ingredients><Instructions>

<Step>Peel the apples</Step><Step>Pour the milk into a 10-inch saucepan</Step>

</Instructions></Recipe>


SUMMER 2002


DTD (Document Type Definition)

XML is extensible because it allows user-defined tags

<!ELEMENT Recipe (Name, Description?, Ingredients?, Instructions?)><!ELEMENT Name (#PCDATA)><!ELEMENT Description (#PCDATA)><!ELEMENT Ingredients (Ingredient)*><!ELEMENT Ingredient (Qty, Item)><!ELEMENT Qty (#PCDATA)><!ATTLIST Qty unit CDATA #REQUIRED><!ELEMENT Item (#PCDATA)><!ATTLIST Item optional CDATA "0"isVegetarian CDATA "true"><!ELEMENT Instructions (Step)+>

DEFINES TAG RecipeHAVING A Name AND3 OPTIONALTAGS

TAGS Name, DescriptionCONTAIN ONLYCHARACTER DATA

TAG IngredientsCONTAINS ZERO ORMORE Ingredient TAGS

Ingredient TAG HAS AQty TAG FOLLOWEDBY AN Item TAG

TAG Qty HAS TWOPOSSIBLE ATTRIBUTES:optional (DEFAULT VALUE 0)isVegetarian (DEFAULT true)

TAG Instructions HAS ONE OR MORE Step TAGSSOURCE: JAVAWORLD

XML COMMENT


SUMMER 2002


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 necessarySOURCE: JAVAWORLD


SUMMER 2002


XSL Extensible Style Language

REWRITING RULES TELLING HOW TO MAP THE CONTENTS OF XML TAGS TO HTML

<xsl> <rule> <target-element type="title"/> <H1 color="red" font-family="Arial"> <children/> </H1> </rule></xsl>

SOURCE: WDVL.COM

PUT THE CONTENTS OF “TITLE” TAGS INTO RED HEADER FONT ARIAL

DO THE SAME FOR THE CHILDREN OF “TITLE” TAGS

LOOK FOR ALL “TITLE” TAGS


SUMMER 2002


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.

• SWIFT• X12 - data exchange standard for business transactions



SUMMER 2002


XML Implementations

• HL7 - health information (Health Level 7)

• EDIFACT/SimplEDI - syntax - repository

• IFX - Interactive Financial Exchange - personal banking.

• – catalogues, supply chain automation

• IOTP – Internet Open Trading Protocol buying, payments

• XBRL – Extensible Business Reporting Language

• XML-enabled product vendor list



SUMMER 2002


Ubiquitous XML Architecture



SUMMER 2002


The Discovery Problem

A mid-sized manufacturer needs to create 400 online relationships with customers, each with their own set of standard and protocols

BroaderB2B

A flower shop in Australia wants to be “plugged in” to every marketplace in the world, but doesn’t know how

SmarterSearch

A B2B marketplace cannot get catalog data for relevant suppliers in its industry, along with connections to shippers, insurers, etc.

Easier Aggregation

Describe Services

Discover Services

IntegrateThemTogether

SOURCE: UDDI.ORG


SUMMER 2002


UDDI(Universal Description, Discovery and Integration)

• Microsoft, IBM, Ariba formed uddi.org• Announced August 31, 2000; endorsed by over 30

companies• Global directory of companies; searchable by

computer• Companies publish machine-readable information

about themselves AND how to conduct ebusiness with them

• Platform-neutral open standard based on XML


SUMMER 2002


UDDI Registry Entries

Entities register informationabout themselves

Standards Bodies, Programmers, Publishers register information about their Service Types (specs)

SOURCE: MICROSOFT


SUMMER 2002


• How to do eCommerce” with us (machine-readable)• Business process (functional)• Service specifications (technical)• Binding information (implementation)• Language/platform/implementation-agnostic

• Business categories: name-value pairs• 3 standard taxonomies in V1:• Industry: NAICS (Industry codes - US Govt.)• Product/Services: UN/SPSC (ECMA)• Location: Geographical taxonomy (ISO 3166)• …more in upcoming releases

• Business name, general business description (in any number of languages)

• Contact info: names, phone numbers, fax numbers, web sites, etc.

• Known identifiers: D-U-N-S, Thomas, domain name, stock ticker symbol, other

UDDI Registry Contents

SOURCE: MICROSOFT


SUMMER 2002


UDDI Operation

Harbour Metals createsonline website with local ASP

1.SydneyNet.com

Marketplaces and search enginesquery UBR, cache Harbour Metals data, and bind to its services

3. Consumers and businesses discover Harbour Metals and do business with it

4.

2.

ASP registersHarbour Metals with UBR

UDDI Registry

SOURCE: UDDI.ORG


SUMMER 2002


Impact of XML

• Interchange mechanism between applications • Rapidly becoming the database language of the Web• XML client/server/server transactions over http:• Permits web data repositories

• XML properties:– Scalable– Maintainable– Easy to use (spreadsheet style skills)– Interoperable (exchange business components)


SUMMER 2002


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 437573746F6D6572 (hex) mean?– Where do fields begin and end?– How about complex data structures (arrays, etc,)?


SUMMER 2002


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 Y2K problem)

• Minimize programmer and development time


SUMMER 2002


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.


SUMMER 2002


Abstract Syntax Notation

• ASN.1 has primitive types:BOOLEAN, INTEGER, REAL, ENUMERATED, BIT STRING, IA5STRING, . . .

• 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


SUMMER 2002


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:

• The string “Customer” would be encoded as 16 08 43 75 73 74 6F 6D 65 72

BOOLEAN 01IA5STRING 16 (8-BIT ASCII)INTEGER 02SEQUENCE 10SET 31

IA5STRING LENGTH8

HEX“C”

HEX“u”

HEX“r”


SUMMER 2002


Basic Encoding Rules

• Content field may be primitive (value) or structured (content has subcomponents)


SUMMER 2002


Basic Encoding Rules

BBCard ::= SEQUENCE { name IA5String (SIZE (1..60)), team IA5String (SIZE (1..60)), age INTEGER (1..100), position IA5String (SIZE (1..60)), handedness ENUMERATED {left-handed(0), right-handed(1), ambidextrous(2)}, batting-average REAL }

“Casey”, “Mudville Nine”, 32, “left field”, ambidextrous, 0.250 (47 bytes of text)

C a s e y M u d v i l l e302D1605 43617365 79160D4D 75647669 6C6C6520 4E696E65 02012016 0A6C6566 74206669 656C640A 01020903 80FE01 (47 bytes in BER)


SUMMER 2002


Using ASN.1/BER

ASN.1COMPILER

ASN.1DEFINITIONS

APPLICATIONPROGRAM

SOURCE LANGUAGE(JAVA, C)

DATA STRUCTURES

APPLICATIONCODE

APPLICATION PROGRAMENCODER/DECODER

(JAVA, C)COMPILER

APPLICATION PROGRAMNOW READS AND WRITESDATA ACCORDING TO BER


SUMMER 2002


ASN.1 Encoding Rules

• BER (Basic) from 1980s– Internet messaging, telephone billing– BER and Java

• DER (Distinguished)– Security applications requiring a unique method of encoding

• CER (Canonical)– For long messages. Encoding can begin before the whole

message has been read

• PER (Packed)– Efficient encodings to reduce bandwidth requirements


SUMMER 2002


Digital Certificates

• Digital certificates are encoded in DER• ASN.1 Primer from RSA

Certificate ::= SEQUENCE {tbsCertificate TBSCertificate, signatureAlgorithm AlgorithmIdentifier, signatureValue BIT STRING }

• Full ASN.1 definition


SUMMER 2002


ASN.1 Applications

• Telephone billing information– Transferred Account Procedure (TAP3)– UMTS (3G phones)

• X9 financial services (checks, electronic funds transfer)• Air-to-ground aircraft information• Electric and gas utilities• Automobile diagnostic monitoring systems• Radio Frequency Identification (RFID)• Biometric IDs (Proposed ANSI Standard X9.84)

– Common Biometric Exchange File Format CBEFF

• Smart cards (ISO 7816-4)• MORE


SUMMER 2002


XML and ASN.1

• Both XML and ASN.1 represent hierarchical (tree-structured) data

• Therefore, one can be translated into the other!• IBM ASN.1/XML translator• We also have XER, the XML encoding rules


SUMMER 2002


QA&

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eCommerce Technology 20-751 Data Interchange