Metadata for Electronic Commerce
These are notes on website design for ANU course "Information Technology in Electronic Commerce" (COMP3410/COMP6341). This section of the course is prepared and presented by Tom Worthington FACS HLM, a Visiting Fellow in the Department of Computer Science at the Australian National University (and Director Tomw Communications Pty Ltd).
Differences Between Metadata for DBMS and E-commerce
- Documents:
- few dozen elements
- Most elements are simple text fields
- Electronic commerce:
- Hundreds of elements
- More qualified and numeric values
Metadata for managing documents (as discussed in the previous section) tends to have a few dozen elements for each document. Most elements are text fields, rather than numeric values or qualified values. Metadata for electronic commerce uses more elements, more qualified and numeric values.
UN/EDIFACT
The United Nations agreed standards for world e-commerce called UN/EDIFACT:
26. United Nations rules for Electronic Data Interchange For Administration, Commerce and Transport. They comprise a set of internationally agreed standards, directories and guidelines for the electronic interchange of structured data, and in particular that related to trade in goods and services between independent, computerized information systems.
27. Recommended within the framework of the United Nations, the rules are approved and published by UN/ECE in the (this) United Nations Trade Data Interchange Directory (UNTDID) and are maintained under agreed procedures.
ANS X12
EDIFACT is one of the two internationally cited family of standards for Electronic Data Interchange (EDI). The other standard is the USA's ANS X12 Syntax. In most cases the same metadata elements can be used with EDIFACT and ANS X12:
This code list is used by United States Government contracting and grant activities to indicate the data expressions that are contained herein. It is designed principally for use with Electronic Date Interchange (EDI) in either the American National Standard X12 syntax or the United Nations/Electronic Data Interchange for Administration, Commerce, and Transport (UN/EDIFACT) syntax. It may be used in other data systems as appropriate, to include as domain values for standard data schemes or as application data. ...
ANS X12 Example
BTA
Small Disadvantaged Business Performing in the US
BTB
Other Small Business Performing in the US
BTC
Large Business Performing in the US
BTD
Javits-Wagner-O'Day Act (JWOD) Participating Nonprofit Agencies
BTF
Hospital
BTL
Foreign Concern/Entity ...
USA Standards for Business Forms
Standards exist for electronic versions of commonly used business forms, such as invoices and Remittance Advice:
810 Invoice - Updated in January 1996 and published as NIST Special Pub 881-10 - ( ASCII, RTF, or PDF ) - Version Control Number: 003040FED01A regenerated as 003040F810_0.
820A Payment Order/Remittance Advice (Automated Standard Application for Payments): Version Control Number 003040F820A1 - updated April 20, 1999 - ( PDF, ASCII, RTF
From: Federal Procurement Code List One (FP1), National Institute of Standards and Technology, 1999 URL: http://snad.ncsl.nist.gov/dartg/edi/3040-ic.html
An XML/EDI: Payment Order
The Interim Report for CEN/ISSS XML/EDI Pilot Project give the example of an XML version of an EDIFACT National Payment Order:
<?xml version="1.0"?> <!DOCTYPE PAY-NAT SYSTEM "pay-nat.dtd"> <PAY-NAT RefNo="0005"> <BGM>AA124</BGM> <DTM1>19980812</DTM1> <DTM1 Type="203">19970815</DTM1> <MOA>100</MOA> <FII Party="OR"> <UKB>010344</UKB> <ACC>23412345</ACC> <ACN>MR N SMITH</ACN>...
Payment Order Elements
Some elements used are:
PAY-NAT
Container for the message segments ... BGM
Identifies the beginning of the message... MOA
Monetary amount of payment. Defaults to GBP
- Pounds sterling ...FII
Container for financial institution information...
XML DTD
Part of the XML document type definition (DTD) of this message is:
...<!ATTLIST PAY-NAT UN-EDIFACT:Prefix CDATA #FIXED "UNH" RefNo CDATA #IMPLIED MessageTypeID CDATA #FIXED "PAYEXT" Version CDATA #FIXED "D" ReleaseNumber CDATA #FIXED "96A" Agency CDATA #FIXED "UN" AssociationCode CDATA #FIXED "SIMP01" > ... <!ELEMENT MOA (#PCDATA) > <!ATTLIST MOA UN-EDIFACT:Prefix CDATA #FIXED "MOA" Type CDATA #FIXED "9" Currency CDATA "GBP" >
This is a reasonably readable example. However, there is a bewildering array of such proposed standards. Also commercial vendors of electronic document and e-commerce products use variations of standards, draft proposed standards, or attempt to create defacto standards based on market dominance.
W3C XML E-commerce Standards
W3C provide a very useful table to compare XML
protocols . As with all good standards development, W3C has been taking
technologies developed by industry and turning them into standards. W3C
started at the bottom end, developing technical document standards and has
more recently working its way up into data definitions, structure,
transaction formats and discovery services.
The XML e-commerce standards are relatively new. There tends to be a heavy
overlap of the companies involved. SOAP was developed by a consortium
of Ariba, Inc., Commerce One, Inc., Compaq, HP, IBM, Microsoft, SAP and other
major companies and is now being standardised by W3C. BizTalk was developed
by Microsoft. WSDL was developed by Ariba, IBM
and Microsoft. Beyond W3C's technical brief there are other standards which
describe specific commercial transactions, such as EbXML from UN/CEFACT oasis.
Making th situation more confusing is the overlap between business domains and technical standards. Early work mixed up the development of what sort of business information could be described (for example a payment advice note) and the format in which the information was encoded (such as in XML). Also many of the standards document are difficult to find, being stored in large PDF documents or at web addresses which change (where is the document defining Microsoft's BiZTalk).
The W3C standards publication process has greatly improved this situation by providing well formatted web documents which are easily found at fixed URLs and by avoiding addressing the business domain. It is easy to find a W3C standard using a web search, to copy a section out of it and paste it (complete with formatting) into a document and to cite the URL of the standard with a reasonable expectation it will still be there when someone goes looking for it. What is needed is for those proposing business standards to follow W3C's lead, by providing documents addressing the business domain and which can be used easily.
WSDL |
|
SOAP |
A lightweight protocol for exchanging structured information in a decentralized, distributed environment. |
XML Schema |
For describing the structure and constraining the contents of XML 1.0 documents |
Document Related Standards
XSL |
|
XSLT |
XSL Transformations: For transforming XML documents into other XML documents. |
XHTML Basic |
XHTML subset for Small Information Appliances |
XML |