1. A process management apparatus adapted to be connected to a network to which a plurality of processing devices are connected, each of the processing devices being capable of executing a requested task and transferring the executed result to a destination designated by the requester of the task, comprising: first management means for allowing access to a predetermined memory in which a cluster list and communication setting information for enabling network communication with each of the clusters are listed, wherein the processing devices are sorted into a single cluster or a plurality of clusters in the cluster list, and the number of sorted processing devices corresponds to the size or kind of the previously estimated task; assigning means for assigning, upon receiving a task demand from any of the processing device through network communication, the task to a specified cluster that is specified by referring the cluster list for a suitable cluster for the size or the kind of the task; and second management means for transferring, to at least one cluster or one processing device selected from the group consisting of the original processing device that requested the task demand and the cluster to which the task is assigned by the assigning means, the communication setting information for the other processing device or other cluster, thereby allowing direct transfer of the executed result between the cluster and the original processing device through network communication.