System and method for schema evolution in an e-commerce network

摘要

A method and computer system are described for conducting commercial transactions by the exchange of electronic documents. The computer system includes a transaction services network, which comprises a plurality of transaction servers for providing services to support commercial transactions. Trading partners operate servers which communicate with the transaction services network via the Internet. The electronic documents are exchanged between trading partners engaged in a transaction. The documents are written in a markup language such as XML. The tags used in the document instances are defined in schemas. Each schema defines a document type, which corresponds to a type of transaction. An enhanced type of XML schema may be used which supports integrity constraints and polymorphism. Schemas are identified by the use of Uniform Resource Names. XML processors residing on transaction servers or trading partner servers parse document instances by retrieving the URNs corresponding to the schemas used to interpret the document. The URNs are converted to location-dependent URIs in order to locate the schemas. URNs are resolved to location-dependent URIs by use of the LDAP protocol. URNs may be converted to LDAP URLs which are used to search LDAP compliant directories. The directories serve as registries for the URI values corresponding to the URNs.