To improve the security of a network by blocking illegal subscription of a node with an incorrectly operating program in the network.

Nodes A-C are respectively provided with management tables 1A-1C in which IP addresses and MAC addresses of all nodes are registered, data extract means 2A-2C extract an IP address and a MAC address of a sender from a frame receiving from other node and discriminate whether or not they are registered in a management table, program confirmation means 3A-3C access a node in unregistered IP and MAC addresses to confirm the presence of an incorrectly operating program, and when the unregistered node has no incorrectly operating program, table data generating processing means 4A-4C register the IP and MAC addresses of the unregistered node to the management table in addition to obtain the communication management system, the communication management equipment, the node and the recording medium recorded with the communication management program.