The new OASIS schemas encompass the Universal Business Language (UBL). UBL is a standard for Extensible Markup Language (XML) document formats that encode business messages, such as purchase orders and invoices. UBL treats business-to-business (B2B) communication across all industry sectors and domains for all types of organizations, including small- and medium-sized businesses.
The draft contains machine-readable XML representations of seven basic business documents, including Order, Order Response, Simple Order Response, Order Cancellation, Despatch Advice, Receipt Advice and Invoice. Together, the representations are intended to allow businesses to implement a generic buy/sell relationship or supply chain whose components slot into existing trade agreements and are immediately understandable by workers in business, supply-chain management (SCM), Electronic Data Interchange (EDI), accounting, customs, taxation and shipping.
OASIS said custom extensions will allow the generic schemas to work in a wide variety of business contexts, and added that many businesses will simply be able to use the generic forms in ordinary business contexts. However, to speed the configuration process for businesses that do need custom extensions, the UBL Technical Committee plans to address automated context configuration in a later draft.
Eventually, OASIS hopes to make UBL a legal standard for international trade, and therefore the technical committee grounded the UBL Library in the Core Component semantics developed for electronic business Extensible Markup Language (ebXML ), a modular suite of specifications for standardizing XML globally in order to facilitate trade between organizations regardless of size. ebXML was jointly developed by OASIS and the United Nations Centre for Trade Facilitation and Electronic Business (UN/CEFACT).
While UBL is not a deliverable of the ebXML initiative, ebXML's Core Component specification is a system for creating idealized, business-context-free models for business information that can be mapped to traditional EDI syntax, XML syntax, or other syntaxes. With UBL, OASIS is trying to take a concrete next-step by mapping the Core Components to XML as an XML Schema representation, thereby allowing for the contextualization of information in an XSD environment.
XML Schemas plan to replace Document Type Definitions (DTDs) as the way to describe and validate data in an XML environment by making relationships much more explicit. XML Schemas define a richer set of datatypes such as booleans, numbers, dates and times, and currencies, which is invaluable for ecommerce applications. DTDs, on the other hand, express datatypes as explicit enumerations, which makes validation much more difficult and less accurate. More important, XML Schemas will make it easier to validate documents based on namespaces (used to qualify element and attributes names by associating them with namespaces identified by URI references. Namespaces prevent identically custom-named tags that may be used in different XML documents from being read the same way), something DTDs cannot do.
The first phase of the project was to deliver a component library and a set of standard B2B document types in the XML Schema form. It also included a set of design rules for creating the schemas and a simple version of a methodology for customizing the schemas.
In addition to the ebXML Core Components, UBL built on the commercial XML Common Business Library, or xCBL, schemas from Commerce One and SAP; early Extensible Style Language (XSL) stylesheet implementations; and the UBL Liaisons Subcommittee.