PURPOSE: To immediately notify other originators of receiver's location without confirming updating of reference count performed by a receiver when a receiver' s location is informed to other originators, as for reference count management in parallel distribution environment.

CONSTITUTION: When an originator A informs a receiver B of receiver's location (1), reference count of the originator A is processed by addition and then both the receiver's lacation and the location of the originator A are informed to the originator B at the same time (2) and (3), and at the time when the data is transmitted to a receiver for the first time, the originator B transmits the requests for sending both receiver's reference count addition request and originator A's reference count subtraction request at the same time (4), and a receiver adds a reference count after receiving data and transmits a request for reference count subtraction to the originator A (5), and the originator A subtracts a reference count after receiving a request for reference count subtraction (6).