Research And Implementation Of Time Sensitive Routing Based On Traffic Shaping

The internal network of the factory is divided into an information network and a control network,both of which work based on Ethernet.Due to the unreliable transmission mechanism of Ethernet,non-real-time information flow and real-time control flow cannot be transmitted in the same network,and the two networks are isolated from each other.With the development of the Industrial Internet,factories are facing a new round of industrial structure upgrading,and the factory's intranet needs to be deeply integrated.Time-sensitive network is compatible with standard Ethernet while supporting the deterministic requirements of control flow transmission.It is a key technology for future factory intranet integration.However,the current standard release is still incomplete.In the face of the urgent need for factory intranet integration,this thesis combines time-sensitive network related standards to design and implement a time-sensitive routing mechanism based on traffic shaping,which can realize the function of time-sensitive network.Time-sensitive routing mechanism realizes the customized service of traffic transmission through two links,which are route selection link and traffic shaping link.The path selection is determined by the routing strategy.The transmission requirements of the mixed service flow of the factory are different,and the traditional routing strategy cannot provide targeted routing services for it.This thesis designs a routing strategy based on variable weights of "hop count" and "bandwidth" suitable for industrial scenarios.This routing strategy analyzes the demand for real-time performance and available bandwidth for traffic transmission in combination with the type of factory traffic,and translated into the demand for the number of hops through the switch and the demand for the available bandwidth.The comprehensive evaluation of the path can finally provide the path selection close to the transmission demand for all kinds of factory flow.At the sending end of the network card on the transmission path,this thesis divides the network card sending queue into types,and uses the kernel priority field as the medium to design a method to guide the corresponding type of traffic into the designated sending queue.Design the real-time stream shaping configuration planning algorithm,cooperate with the gating mechanism added in the real-time stream queue,divide the time slice transmission for the real-time stream,and make the end-to-end delay of the transmission controllable.Design the audio and video stream shaping configuration planning algorithm,and cooperate with the credit-based shaping mechanism added in the audio and video stream queue to make the audio and video stream smoothly send data to the network.The design of the traffic shaping link is the fundamental means of this article to ensure the transmission requirements of the various traffic of the factory.In order to carry the time-sensitive routing mechanism,this thesis builds a software-defined centralized network,and designs a centralized controller that includes information collection services,routing services,and traffic shaping services.The controller can collect traffic and network resource information,customize services for factory traffic,and deliver the service configuration to the switch through the two configuration delivery paths designed in this thesis.Finally,this thesis tests the time-sensitive routing mechanism,and the results show that the routing mechanism can support the transmission requirements of industrial mixed service traffic,and it is compatible with the transmission of other non-real-time traffic while ensuring the authentic transmission of real-time traffic.The work of this thesis is of great significance to the integration of the factory intranet.