To perform charging (meter rate) corresponding to an information amount to a user by gathering information usable for charging such as the number of packets transferred to respective users, the number of the bytes of the packets and the number of the bytes of user data for the respective users.

In a router 1 for constituting the computer network of a connectionless type, the number of the packets for respective destination addresses, the number of the bytes of the packets and the number of the bytes of the user data which are basic information for charging are gathered. For that, the router 1 is provided with transmission/reception parts 5, 6 and 7 for transmitting and receiving the packets, a header analysis part 2 for reading the destination address and a data length and a charging information storage part 3, for holding a charging information table for storing the number of the packets and the number of the bytes for the respective destination addresses.