cXML (commerce eXtensible Markup Language) is a protocol, created by Ariba, intended for communication of business documents between procurement applications, e-commerce hubs and suppliers. cXML is based on XML and provides formal XML schemas for standard business transactions, allowing programs to modify and validate documents without prior knowledge of their form.
http://en.wikipedia.org/wiki/CXML
http://en.wikipedia.org/wiki/CXML