A data management unit stores therein configuration items including attribute items described according to different schemas. A dictionary candidate retrieval unit specifies a combination of a pair of attribute items, which defines a correspondence relation between the attribute items of the different schemas, as a dictionary definition item, and retrieves, as a dictionary candidate, a combination of the attribute names corresponding to the same attribute value in the attribute items, which are described according to the schemas, of the dictionary definition item from the data management unit. A dictionary generation unit generates dictionary information defining synonymity between the attribute names of the different attribute items described according to the different schemas based on the dictionary candidate retrieved by the dictionary candidate retrieval unit. A dictionary management unit stores therein the dictionary information generated by the dictionary generation unit.