This paper proposes to apply the prediction of coming traffic for routing named 4 dimensional traffic engineering (4D-TE). Current TE can optimize the usage of network resource by dynamic control depending on an instant status of the network, not for long period. The 4D-TE reflects not only current actual traffic but also coming traffic transition, that is, time as fourth dimension is added for an optimum route search. It predicts traffic transition by referring past statistical data and allocates the minimum cost route for coming large traffic. This paper clarifies how much effectiveness we can get by the 4D-TE. Then, this paper describes the required functions such as traffic pattern management, the prediction of traffic transition and optimum route calculation, and shows how to define link cost for route calculation. Finally, concerning the architecture of control plane for the 4D-TE, the performance of hierarchical architecture is modeled and evaluated.