To allow a multimedia terminals equipment to secure a data transmission period with setting of a credit without decreasing the number of nodes connected to a LAN.

A token has the number of terminal equipment possible for data transmission as a circuit and a multimedia terminal equipment 2 requiring real time performance for data transmission sets a terminal equipment number required to secure a data transmission period as a credit. Then conventional terminal equipment 11-1N not requiring real time performance for data transmission conduct data transmission when the credit receiving the token is not zero when the transmission data are in existence, the number of credits is decreased by 1 and the token is given to a succeeding terminal equipment. Thus, while ensuring the data transmission period of the multimedia terminal equipment, reduction in the number of nodes is avoided.