PURPOSE: To improve the transmission throughput of the whole of a network by giving a prescribed abandonment rate to all packets independently of the number of packet switching nodes through which packets pass.

CONSTITUTION: The packet switching network is provided with terminals 1, switching nodes 2, network control parts 3, subscriber lines 4, trunk lines 5, packets 6, terminal interfaces 7, and terminals 8 requiring the terminal interfaces. Since the number of repeating nodes for packets 6 is checked in the case of communication between terminals 1 and the abandonment rate of packets 6 in each switching node 2 is changed in accordance with the value of the number of repeating nodes, the abandonment rate is not increased according as the number of repeating nodes is increased, and the prescribed abandonment rate of packets 6 is set independently of the number of repeating nodes. Thus, the throughput of the whole of the network is improved.