Linked Data Platform (LDP) is a linked data specification defining a set of integration patterns for building RESTful HTTP services that are capable of read/write of RDF data.
The Linked Data Platform allows use of RESTful HTTP to consume, create, update and delete both RDF and non-RDF resources. [1] In addition, it defines a set of "container" constructs – buckets into which documents can be added with a relationship between the bucket and the object similar to the relationship between a blog and its constituent blog posts. [2]
LDP evolved from work at IBM's Rational Product Group for application integration. Starting in 2010, IBM looked at linked data for application lifecycle management and sought what was an alternative means for read–write linked data.
IBM joined with the W3C in June 2012 to form a W3C working group, which operated until July 2015. [3] [4] On 26 February 2015, the W3C Linked Data Platform 1.0 was approved as a W3C Recommendation. [5]
Read–write linked data was previously described using WebDAV and SPARUL [6] by Tim Berners-Lee in his design issues [7] [8] that built upon his four principles for linked data. [9]
The Linked Data Platform includes Tim Berners-Lee's four principles, and focuses on the following concepts. [10]
LDP is not a file system, but it uses linked data to produce the kind of information that can be used to create a modern file system abstraction for interacting with HTTP-accessible resources (colloquially referred to as "Web resources").
In contrast, WebDAV is a "set of extensions to the HTTP protocol which allows users to collaboratively edit and manage files on remote web servers". [11]
However, LDP can be used with WebDAV. For example, there are live LDP containers in the wild, identified by linked data URIs, that can also function as WebDAV endpoints (i.e., mountable by any WebDAV compliant user agent).
HTTP is an application layer protocol in the Internet protocol suite model for distributed, collaborative, hypermedia information systems. HTTP is the foundation of data communication for the World Wide Web, where hypertext documents include hyperlinks to other resources that the user can easily access, for example by a mouse click or by tapping the screen in a web browser.
The Semantic Web, sometimes known as Web 3.0, is an extension of the World Wide Web through standards set by the World Wide Web Consortium (W3C). The goal of the Semantic Web is to make Internet data machine-readable.
The Resource Description Framework (RDF) is a World Wide Web Consortium (W3C) standard originally designed as a data model for metadata. It has come to be used as a general method for description and exchange of graph data. RDF provides a variety of syntax notations and data serialization formats, with Turtle currently being the most widely used notation.
A web service (WS) is either:
WebDAV is a set of extensions to the Hypertext Transfer Protocol (HTTP), which allows user agents to collaboratively author contents directly in an HTTP web server by providing facilities for concurrency control and namespace operations, thus allowing Web to be viewed as a writeable, collaborative medium and not just a read-only medium. WebDAV is defined in RFC 4918 by a working group of the Internet Engineering Task Force (IETF).
The Extensible Metadata Platform (XMP) is an ISO standard, originally created by Adobe Systems Inc., for the creation, processing and interchange of standardized and custom metadata for digital documents and data sets.
FOAF is a machine-readable ontology describing persons, their activities and their relations to other people and objects. Anyone can use FOAF to describe themselves. FOAF allows groups of people to describe social networks without the need for a centralised database.
A web resource is any identifiable resource present on or connected to the World Wide Web. Resources are identified using Uniform Resource Identifiers (URIs). In the Semantic Web, web resources and their semantic properties are described using the Resource Description Framework (RDF).
Notation3, or N3 as it is more commonly known, is a shorthand non-XML serialization of Resource Description Framework models, designed with human-readability in mind: N3 is much more compact and readable than XML RDF notation. The format is being developed by Tim Berners-Lee and others from the Semantic Web community. A formalization of the logic underlying N3 was published by Berners-Lee and others in 2008.
RDFa or Resource Description Framework in Attributes is a W3C Recommendation that adds a set of attribute-level extensions to HTML, XHTML and various XML-based document types for embedding rich metadata within Web documents. The Resource Description Framework (RDF) data-model mapping enables its use for embedding RDF subject-predicate-object expressions within XHTML documents. It also enables the extraction of RDF model triples by compliant user agents.
Simple Knowledge Organization System (SKOS) is a W3C recommendation designed for representation of thesauri, classification schemes, taxonomies, subject-heading systems, or any other type of structured controlled vocabulary. SKOS is part of the Semantic Web family of standards built upon RDF and RDFS, and its main objective is to enable easy publication and use of such vocabularies as linked data.
Virtuoso Universal Server is a middleware and database engine hybrid that combines the functionality of a traditional relational database management system (RDBMS), object–relational database (ORDBMS), virtual database, RDF, XML, free-text, web application server and file server functionality in a single system. Rather than have dedicated servers for each of the aforementioned functionality realms, Virtuoso is a "universal server"; it enables a single multithreaded server process that implements multiple protocols. The free and open source edition of Virtuoso Universal Server is also known as OpenLink Virtuoso. The software has been developed by OpenLink Software with Kingsley Uyi Idehen and Orri Erling as the chief software architects.
Semantic publishing on the Web, or semantic web publishing, refers to publishing information on the web as documents accompanied by semantic markup. Semantic publication provides a way for computers to understand the structure and even the meaning of the published information, making information search and data integration more efficient.
Semantically Interlinked Online Communities Project is a Semantic Web technology. SIOC provides methods for interconnecting discussion methods such as blogs, forums and mailing lists to each other. It consists of the SIOC ontology, an open-standard machine-readable format for expressing the information contained both explicitly and implicitly in Internet discussion methods, of SIOC metadata producers for a number of popular blogging platforms and content management systems, and of storage and browsing/searching systems for leveraging this SIOC data.
In computing, linked data is structured data which is interlinked with other data so it becomes more useful through semantic queries. It builds upon standard Web technologies such as HTTP, RDF and URIs, but rather than using them to serve web pages only for human readers, it extends them to share information in a way that can be read automatically by computers. Part of the vision of linked data is for the Internet to become a global database.
OpenSocial is a public specification that outlines a set of common application programming interfaces (APIs) for web applications. Initially designed for social network applications, it was developed collaboratively by Google, MySpace and other social networks. It has since evolved into a runtime environment that allows third-party components, regardless of their trust level, to operate within an existing web application.
In computing, POST is a request method supported by HTTP used by the World Wide Web. By design, the POST request method requests that a web server accepts the data enclosed in the body of the request message, most likely for storing it. It is often used when uploading a file or when submitting a completed web form.
JSON-LD is a method of encoding linked data using JSON. One goal for JSON-LD was to require as little effort as possible from developers to transform their existing JSON to JSON-LD. JSON-LD allows data to be serialized in a way that is similar to traditional JSON. It was initially developed by the JSON for Linking Data Community Group before being transferred to the RDF Working Group for review, improvement, and standardization, and is currently maintained by the JSON-LD Working Group. JSON-LD is a World Wide Web Consortium Recommendation.
Apache Marmotta is a linked data platform that comprises several components. In its most basic configuration it is a Linked Data server. Marmotta is one of the reference projects early implementing the new Linked Data Platform recommendation that is being developed by W3C.
Linked Data Notifications (LDN) is a W3C Recommendation that describes a communications protocol based on HTTP, URI, and RDF on how servers (receivers) can receive messages pushed to them by applications (senders), as well as how other applications (consumers) may retrieve those messages. Any web resource can advertise a receiving endpoint (inbox) for notification messages. Messages are expressed in RDF, and can contain arbitrary data.