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Simple Semantic Web Architecture and Protocol (SSWAP pronounced "swap") is a lightweight, document-centric protocol and architecture for the Semantic Web. Employing notions drawn from REST, Web Ontology Language (OWL), and web services, SSWAP makes possible a scheme for information sharing and service invocation that allows information producers and consumers to coordinate their efforts in a decentralized and bottom-up fashion. Using SSWAP, users can create systems to enable creation, discovery and execution of RESTful and other web services. SSWAP utilizes Web Ontology Language (OWL) ontologies to describe the features and capabilities of web services and standard HTTP methods to execute these web services. ==Overview== SSWAP aims to combine web services and semantic web technologies to enable high-throughput discovery, assessment, and integration of data and services between distributed parties. Semantic Web ontologies encoded in OWL are used to describe information about a web service such as the service category, types of input the service consumes, and the types of output the service produces. Using ontologies to describe such properties makes the service descriptions amenable to automated reasoning methods and allows inferencing to be used for tasks such as searching for service descriptions, basic matchmaking, and determining if the output of a service can be used as input to another service. SSWAP differs from other Semantic Web Services architectures (the most prominent ones being OWL-S and (SA-WSDL )) by not adopting the XML-based Web Service technologies such as WSDL and SOAP. Instead, SSWAP adopts a simple approach based on a RESTful architecture. Services are identified by a URI and standard HTTP methods GET and POST are used to access the service descriptions and to invoke the services, respectively. SSWAP does not specify rules for authentication or security; but it is designed to work on protocols such as SSL and HTTPS that already address these issues. At its core SSWAP is an OWL ontology specifically designed to describe web services. In SSWAP a service represents nothing more than an mapping from its inputs to its outputs. The SSWAP ontology defines a small set of terms that can be used to describe this transformation. The same representation is also used for service search requests and responses, as well as service execution requests and responses. This representation can be thought of as an RDF graph template. There are immutable parts of the template, called the "canonical graph", that unambiguously establishes the web resource performing the service, as well as the subject and object of the service mapping. The mutable parts annotate this canonical structure, allowing the use of arbitrary OWL constructs to optionally refine the service's class and the subject and object mappings. For example, a service execution request fills in the value of an input parameter; but it leaves the output value blank, which is then filled as a result of the service execution and returned as the response. Thus, SSWAP defines a protocol where clients and servers exchange OWL documents that contain this graph structure for accomplishing the tasks of services discovery and execution. SSWAP ontology is not domain-specific and can be combined with arbitrary domain ontologies to represent the relevant types of services, inputs, or outputs. But a distinctive feature of SSWAP is that it defines a ''convention'' for partitioning domain ontologies into smaller parts, such that each term definition (for a class, property, or an individual) is stored in a separate ontology document. According to SSWAP, the definition of a term to be all axioms whose subject is the term being defined. An existing ontology can be automatically partitioned into multiple term definition ontologies by adopting this convention. A term definition ontology is smaller compared to the original ontology because it contains a subset of the original axioms. In addition, SSWAP requires that the URIs that identify terms should not use fragment identifiers. These two conventions make sure that dereferencing a term URI will retrieve the definition ontology for that term. This makes it easier to use terms from very large ontologies to describe web services since the service description can refer to only the terms relevant for its functionality and only retrieve the corresponding definition ontologies rather the one large ontology that contains all the terms. The definition of a term (as described in SSWAP) does not contain all the inferences about the term that can be computed from the original ontology. The partitions of the ontology are still connected to each other using the standard OWL import mechanism and all the terms can be combined into a meta-ontology to compute the complete logical consequences of the original ontology. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「SSWAP」の詳細全文を読む スポンサード リンク
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