]> $Id$ Discovery is the act of locating a machine-processable description of a Web service that may have been previously unknown and that meets certain functional criteria. The goal is to find an appropriate Web service. Discovery performed_by Discovery may be performed by an agent, or by an end-user realized_by Discovery may be realized using a discovery service Discovery_Service A discovery service is a service that enables agent to discover resources and expecially Web services. A discovery service is a service publish A discovery service is used to publish (resource) descriptions indexes A discovery service indexes resource descriptions search A discovery service is used to search for resources requested A discovery service may be requested by an agent Identifier An identifier is an opaque string of bits that may be used to associate with a resource. id an identifier is an opaque string of bits (2.3.3.3.2) Here I do map an identifier to a string realized_by An identifier may be realized as a URI (2.3.3.3.2) identify An identifier identifies a resource that is relevant to the architecture Representation A representation is a data object that denotes a resource state, and is the vehicle for conveying the meaning of a resource. Resource A resource is defined by [RFC2396] to be anything that has an identifier. Although resources in general can be anything, this architecture is only concerned with those resources that are relevant to Web services and therefore have some additional characteristics. In particular, they incorporate the concepts of ownership and control: a resource that appears in this architecture is a thing that has a name, may have reasonable representations and which can be said to be owned. The ownership of a resource is critically connected with the right to set policy on the resource. (2.3.3.5.1) identifier A resource has an identifier (2.3.3.5.2) representation a resource may have zero or more representations (2.3.3.5.2) representation a resource may have zero or more resource description (2.3.3.5.2) owned_by a resource is owned by a person or an organization (2.3.3.5.2) governed_by a resource may be governed by zero or more policies (2.3.3.5.2) Resource_Description A resource description is any machine readable structure that may permit resources to be discovered. Resource descriptions may be of many different forms, tailored for specific purposes, but all resource descriptions must contain the resource's identifier. (2.3.3.6.1) contain A resource description contains the resource's identifier (2.3.3.6.2) Used concept Identifier instead of defining Resource_Identifier describe A resource description describes the resource in a predictable way. (2.3.3.6.2) I am not sure what does it mean "in a predictable way" reference A resource description may reference the policies applicable to the resource (2.3.3.6.2)