The explosive increase of smart devices and mobile traffic results in heavy burden on backhaul and core network,intolerable network latency and degraded service to the end-users.As a complement to core network,edge network contributes to relieving network burden and improving user experience.To investigate the problem of optimizing the total consumption in an edge-core network,the system consumption minimization problem is fromulated,considering the energy consumption and delay.Given that the formulated problem is a mixed nonlinear integer programming (MNIP),a low-complexity workload allocation algorithm is proposed based on interior-point method.The proposed algorithm has an extremely short running time in practice.Finally,simulation results show that edge network can significantly complement core network with much reduced backhaul energy consumption and delay.