Document management device, communications terminal device, document management program, communications control program and document management system

摘要

A document management device obtains thumbnail information as to a requested document out of an image transmitted via a public network, judges as to whether the thumbnail information is correct with respect to the requested document, and returns the requested document when correct. This prevents a person having no knowledge of the thumbnail information from obtaining a document from a device main body, thereby tightening security for document management in the main body and providing the document management device capable of fully managing even a document requiring higher security.