"ogator can make communication with each other, wherein N is a positive integer equal to or greater than two, (b) binary-searching the number space in each of the first to N-th communication areas one by one to identify a responder(s) existing therein, and (c) inactivating the thus identified responder(s), wherein the steps (a), (b) and (c) are carried out by the host computer. [0060] It is prefera" . . . .