To store the log of a system which performs distribution processing in easy-to-use form.

When an information processor 1 is requested to execute the prescribed processing, a specific information generation means 1b generates the specific information as the unique information. An arithmetic processing part 1a supplies the specific information to an information processor 3 via a transmitting means 1c and a network 2. The logs to which the specific information is added when the processors 1 and 3 execute each prescribed operation are recorded to the log recording means 1e and 3e. If a request is received from an input means 1f to collect the logs concerning the prescribed processing, the specific information corresponding to the processing is acquired and the logs having the specific information are acquired from the means 1e and 3e.