XDI
Encyclopedia
XDI is a generalized, extensible service for sharing, linking, and synchronizing structured data over the Internet and other data networks using XRI-addressable RDF
graphs. XDI is under development by the OASIS
XDI Technical Committee.
The main features of XDI are: the ability to link and nest RDF graphs to provide context; full addressability of all nodes in the graph at any level of context; representation of XDI operations as graph statements so authorization can be built into the graph (a feature called XDI link contracts); standard serialization formats including JSON and XML; and a simple ontology language for defining shared semantics using XDI dictionary services.
XDI graphs can be serialized in a number of formats, including XML
and JSON
. Since XDI documents are already fully structured, XML adds very little value, so JSON is the preferred serialization format. The XDI protocol can be bound to multiple transport protocols. The XDI TC is defining bindings to HTTP and HTTPS
, however it is also exploring bindings to XMPP and potentially directly to TCP/IP.
XDI provides a standardized portable authorization format call XDI link contract
s. Link contracts are themselves XDI documents (which may be contained in other XDI documents) that enable control over the authority, security, privacy, and rights of shared data to be expressed in a standard machine-readable format and understood by any XDI endpoint.
This approach to a globally distributed data sharing network models the real-world mechanism of social contract
s and legal contracts that bind civilized people and organizations in the real world today. Thus XDI can be a key enabler of the Social Web
. It has also been cited as a mechanism to support a new legal concept, Virtual Rights, which are based on a new legal entity, the "virtual identity", and a new fundamental right: "to have or not to have a virtual identity".
Public services based on the OASIS XRI and XDI specifications are under development by an international non-profit organization, XDI.ORG.
Resource Description Framework
The Resource Description Framework is a family of World Wide Web Consortium specifications originally designed as a metadata data model...
graphs. XDI is under development by the OASIS
OASIS (organization)
The Organization for the Advancement of Structured Information Standards is a global consortium that drives the development, convergence and adoption of e-business and web service standards...
XDI Technical Committee.
The main features of XDI are: the ability to link and nest RDF graphs to provide context; full addressability of all nodes in the graph at any level of context; representation of XDI operations as graph statements so authorization can be built into the graph (a feature called XDI link contracts); standard serialization formats including JSON and XML; and a simple ontology language for defining shared semantics using XDI dictionary services.
XDI graphs can be serialized in a number of formats, including XML
XML
Extensible Markup Language is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards....
and JSON
JSON
JSON , or JavaScript Object Notation, is a lightweight text-based open standard designed for human-readable data interchange. It is derived from the JavaScript scripting language for representing simple data structures and associative arrays, called objects...
. Since XDI documents are already fully structured, XML adds very little value, so JSON is the preferred serialization format. The XDI protocol can be bound to multiple transport protocols. The XDI TC is defining bindings to HTTP and HTTPS
Https
Hypertext Transfer Protocol Secure is a combination of the Hypertext Transfer Protocol with SSL/TLS protocol to provide encrypted communication and secure identification of a network web server...
, however it is also exploring bindings to XMPP and potentially directly to TCP/IP.
XDI provides a standardized portable authorization format call XDI link contract
Link contract
A link contract is an approach to data control in a distributed data sharing network. Link contracts are fundamental to Dataweb technology and a key feature of the XDI specifications under development at OASIS....
s. Link contracts are themselves XDI documents (which may be contained in other XDI documents) that enable control over the authority, security, privacy, and rights of shared data to be expressed in a standard machine-readable format and understood by any XDI endpoint.
This approach to a globally distributed data sharing network models the real-world mechanism of social contract
Social contract
The social contract is an intellectual device intended to explain the appropriate relationship between individuals and their governments. Social contract arguments assert that individuals unite into political societies by a process of mutual consent, agreeing to abide by common rules and accept...
s and legal contracts that bind civilized people and organizations in the real world today. Thus XDI can be a key enabler of the Social Web
Social Web
The social Web is a set of social relations that link people through the World Wide Web. The Social web encompasses how websites and software are designed and developed in order to support and foster social interaction. These online social interactions form the basis of much online activity...
. It has also been cited as a mechanism to support a new legal concept, Virtual Rights, which are based on a new legal entity, the "virtual identity", and a new fundamental right: "to have or not to have a virtual identity".
Public services based on the OASIS XRI and XDI specifications are under development by an international non-profit organization, XDI.ORG.
See also
- XRI
- XRDSXRDSXRDS is an XML format for discovery of metadata about a resource – in particular discovery of services associated with the resource, a process known as service discovery...
- link contractLink contractA link contract is an approach to data control in a distributed data sharing network. Link contracts are fundamental to Dataweb technology and a key feature of the XDI specifications under development at OASIS....
- i-nameI-nameI-names are one form of an XRI — an OASIS open standard for digital identifiers designed for sharing resources and data across domains and applications. I-names are human readable XRIs intended to be as easy as possible for people to remember and use. For example, a personal i-name could be =Mary...
- i-numberI-numberi-numbers are a type of Internet identifier designed to solve the problem of how any resource can have a persistent identity that never changes even when the resource moves or changes its human-friendly name...
- i-brokerI-brokerAn i-broker is a "banker for data" or "ISP for identity services" — a trusted third party that helps individuals and organizations share private data the same way banks help exchange funds and ISPs help exchange e-mail and files. The term was introduced in the Social Web paper describing how a new...
- Social WebSocial WebThe social Web is a set of social relations that link people through the World Wide Web. The Social web encompasses how websites and software are designed and developed in order to support and foster social interaction. These online social interactions form the basis of much online activity...
- OpenIDOpenIDOpenID is an open standard that describes how users can be authenticated in a decentralized manner, eliminating the need for services to provide their own ad hoc systems and allowing users to consolidate their digital identities...
- Higgins project
External links
- OASIS XDI TC wiki page with links to documents explaining the XDI graph model
- JSON serialization format
- OASIS XDI Technical Committee
- OASIS XRI Technical Committee
- XDI.ORG
- The Social Web: Creating An Open Social Network with XDI in the Planetwork Journal.
- Virtual Rights
Implementations
- XDI reference implementation in Java (includes a number of utilities for experimenting directly with XDI, although in older serialization formats)