Packet forwarding device

A packet forwarding device changes packet transfer performance according to a packet load, and ensures communication quality of an important packet while transfer performance is made minimum to suppress power consumption. The packet forwarding device includes a measuring section to measure the packet load for each packet importance degree, an estimation section to estimate a future packet load for each importance degree based on the measurement result, a performance determination section to determine performance for an operation based on the estimated load, which are provided in, for example, a traffic estimation/performance determination section. Reduction in the power consumption and assurance of the communication quality of the important packet are realized by a minimum performance determination based on an important packet estimation load in the performance determination section and a preferential process of the important packet in the packet forwarding device.