Implementation Methods

An information model described in EXPRESS can be compared to a conceptional schema description for databases. This means it is still independent from a concrete implementation, but is already available in computer-interpretable form. Thus it is possible to map such a logic model (specification) into different application systems with the aid of software tools. In STEP are considered:

		Physical File Exchange for the exchange of product data in a sequential file (ISO 10303-21).
		XML representation of EXPRESS schemas and data (ISO 10303-28).
		An Application Programming Interface (API) to access product data, which is stored in an arbitrary system and described with an EXPRESS schema. This Part of STEP (ISO 10303-22) bears the name Standard Data Access Interface (SDAI). Associated is the definition of
		Language bindings of the SDAI in C++ (ISO 10303-23), C (ISO 10303-24) and IDL (Interface Definition Language) (ISO 10303-26).
		Data Sharing as denotation for the transparent access from application programs to a logical databasis, which is described by an EXPRESS schema and is possibly physically distributed in a network. The development and standardization of specifications for this purpose is currently subject of several research projects.
		The long-term archiving of product data, e.g. according to the regulations for product liability.

ISO 10303	Name:	Status: 05/02
21	Clear text encoding of the exchange structure	IS
22	Standard data access interface	IS
23	C++ language binding to SDAI	IS
24	C Language Binding to SDAI	IS
25	EXPRESS to OMG XMI	WD
26	CORBA IDL Language Binding to SDAI	canceled
27	Java Language Binding to SDAI	IS
28	XML representation for EXPRESSS-driven	DTS
29	Ltwt JAVA binding	CD

IS - International Standard
CD - Committee Draft
WD - Working Draft
DTS - Draft Technical Specification

Latest status see: http://www.nist.gov/sc5/soap/