Abstract: The technology of software defined networking（SDN）has provided the intelligent network with a new line of thought.But at the same time,control delay is introduced into the end-to-end transmission delay of transaction.The influence of hardware resources and flow table release mode on control delay is described in detail under the SDN architecture.In the simulation environment and actual test,comparisons of end-to-end time delay and control time delay with application systems are made.From the data analysis,it can be seen that the Reactive mode has a high degree of automation and flexibility,but introduces high control delay.However,the Proactive mode has a low control delay,but requires manual intervention and preconfiguration.Based on the comparison conclusions and combined with business bearer of current network,it is suggested that the bearer mode involved in routing in the power communication network be optimized by SDN technology.Proactive mode guarantees real-time performance by pre-configuring service paths,while supporting Reactive mode to meet the flexibility requirements of complicated networks.