PURPOSE: To efficiently collect a history by collecting the history of the vicinity in which a processing request, etc., have been informed from some device to the other device and the history of the vicinity in which abnormality has been generated or time-out has occurred.

CONSTITUTION: After a device 1 has informed a processing request to a device 2, when there is no response until a prescribed time t1 elapse, write to the first history memory 1-1 is stopped, and also, by taking an opportunity of the generation of some abnormality, or taking an opportunity of a fact that there is no response from the other device 2 until a prescribed time t2 elapses and time-out has occurred, write to the second history memory 1-2 is stopped. Accordingly, a history of the vicinity (about) in which a processing request, etc., have been informed to the other device is collected in the first history memory, and also, a history of the vicinity of a time point when abnormality has been generated or a time point when time-out has occurred is collected in the second history memory. In such a way, the history between the devices for executing the processing by a noticed and a response can be collected efficiently.