Billing processing system, a network switch, a network management server, the accounting processing method, and a charging processing program

Billing processing system comprises a communication network, a billing server for billing for the communication in a communication network determines a communication path communicating a management server that sets the routing information to the network switch. Billing server stores the billing class information for each user for charging. The management server sets the billing class information together with route information to the billing network switch that is arbitrarily selected in the communication path. Billing network switch generates billing information by the billing calculation using the billing class information every time the transfer of the communication packet. Management server, the communication is completed, and transmits the billing network switch to the charging server acquires the billing information.