Patent ID: 7159019

Claim:
A system for collecting information in a plurality of host computers through a network, each of the plurality of host computers having a database, the system comprising: in at least one of the plurality of host computers, a management unit configured to store a management table representing a correspondence between an information identifier of requested information and a host identifier of each of those host computers that store the requested information; and in each of the plurality of host computers: a correspondence acquirement unit configured to acquire a correspondence relation information between the information identifier of the requested information and host identifiers of host computers each storing the requested information by referring to the management table, in response to an information retrieval request with the information identifier, a first decision unit configured to choose at least one of the host computers from which to retrieve the requested information by referring to the correspondence relation information, a second decision unit configured to evaluate a retrieval time cost of each of a plurality of retrieval methods used for the at least one host computer, the plurality of retrieval methods including a remote retrieval and a mobile agent retrieval, and to select one retrieval method whose retrieval time cost is minimum from the plurality of retrieval methods, wherein the remote retrieval represents that the information retrieval request is sent to the chosen at least one host computer from which the requested information is to be retrieved and that a result of the information retrieval request is received from the chosen at least one host computer, and wherein the mobile agent retrieval represents that an executable retrieval program including the information retrieval request is sent to the chosen at least one host computer from which the requested information is to be retrieved for local execution, and that a result of the information retrieval request is added to the executable retrieval program and then returned to the host computer sending the executable retrieval program; and a retrieval unit configured to retrieve the requested information, based on the one retrieval method from the at least one host computer.