XRI Data Interchange as defined by the XDI Specifications.

XDI (XRI Data Interchange) is a generalized, extensible service for sharing, linking, and synchronizing data over the Internet and other data networks using XML documents and XRIs (Extensible Resource Identifiers). The XDI protocol is under development by the OASIS http://www.oasis-open.org/committees/xdi XDI Technical Committee.