1. A context providing method comprising: recording, in a context holding unit, a plurality of context information, wherein each context information includes a context entity identifier for distinguishing a context entity from other context entities, various information representing a state of the context entity, and association information; receiving a request for information representing the state of a first context entity; using a context generation unit, in response to the received request, from said context holding unit, extracting the context information of the first context entity, extracting the context information of a second context entity which is registered as the association information in the context information of the first context entity, and executing, at least once, a process of extracting the context information of a third context entity which is registered as the association information in the extracted context information excluding the context information of the first context entity, but not registered as the association information in the context information of the first context entity, to determine, as the information representing the state of the first context entity, the information contained in any of the extracted context information; and sending back the information determined by said context generation unit to respond to the request.
1. A context providing method comprising: recording, in a context holding unit, a plurality of context information, wherein each context information includes a context entity identifier for distinguishing a context entity from other context entities, various information representing a state of the context entity, and association information; receiving a request for information representing the state of a first context entity; using a context generation unit, in response to the received request, from said context holding unit, extracting the context information of the first context entity, extracting the context information of a second context entity which is registered as the association information in the context information of the first context entity, and executing, at least once, a process of extracting the context information of a third context entity which is registered as the association information in the extracted context information excluding the context information of the first context entity, but not registered as the association information in the context information of the first context entity, to determine, as the information representing the state of the first context entity, the information contained in any of the extracted context information; and sending back the information determined by said context generation unit to respond to the request. 4. The context providing method according to claim 1 , further comprising: collecting context information via a network, and, when information containing a first context entity identifier and a second context entity identifier has been collected, adding one of the context entity identifiers, as the association information, to the context information containing the other context entity identifier.