We are developing an optical layer2 switch network that uses both wavelengthdivision multiplexing and timedivision multiplexing technologies for efficient traffic aggregation in metro networks.For efficient traffic aggregation,path bandwidth control is key because it strongly affects bandwidth efficiency.For this paper,we propose a dynamic timeslot allocation method that uses periodic information of difference values of traffic variation.This method can derive nearoptimal allocation with lower computational cost,which enlarges the maximum available network size compared with conventional timeslot allocation methods.Numerical results show that the proposed method enables dynamic path control in 1Knodescale optical layer2 switch network,which leads to costeffective metro networks.