Design of optical aggregation network with carrier edge functions virtualization

NFV (network functions virtualization) enables carrier edge functions to be relocated from dedicated hardware to distributed pools of commodity servers, which reduces network cost and improves robustness to unpredictable demand changes. The key to this lies in how to place each VNF (virtual network function) on an adequate server among pools in conjunction with design of paths connecting servers with OLTs (optical line terminals). There have been extensive studies regarding VNF placement problems, but few have investigated the optimal placement of VNFs in consideration of carrier edge function virtualization. We thus study a design problem of carrier edge VNF placement in an optical aggregation network. We formulate a design problem as MILP (mixed-integer linear programming) and demonstrate the effectiveness of the proposed method through intensive mathematical experiments. The experiments showed that the proposed method reduced the maximum server load and network cost by up to by 29% and 21%, respectively.