Research Of High Speed Network Traffic Generation Method For Simulation Application

At present,the application of simulation is more and more distributed and networked.With the increase of the scale of the simulation application,the number of nodes,the size and frequency of the interactive data of the nodes are increasing rapidly.Network as a simulation system of the various resources of the connector,the data transmission speed,the correct rate and other indicators to become the key factors affecting the simulation results.To ensure the normal operation of the network based simulation components,the design and implementation phase of the simulation application,test and verify the operation of various physical devices on the network,also known as network testing.Network testing depends on the degree of similarity between the traffic on the network and the real traffic.Network traffic data of large scale simulation based on network demand higher speed and precision.In view of the simulation application,the network flow simulation method plays an important role in the accurate control of large scale simulation applications.Network packet simulation application usually consists of interactive data and interactive instruction,from the microscopic point of view,the data packet carries all the information of the data;from the perspective of a higher level,with a correlation between data packets,reflects the interaction between simulation components.Therefore,this paper based on the existing data packet generation technology,combined with the results of software and hardware collaboration technology,from the two levels of data packet generation and data flow to carry out research on network traffic.The main results include:1.A high speed network data packet simulation system is designed for large scale simulation applications.The system is based on FPGA(Field-Programmable Gate Array),with its high speed and high precision processing capabilities,with fast access to host large storage space,while maintaining the FPGA processing ability,the playback system data file to restore the processing power from the order of MB to GB.In order to improve the performance of data transmission between the host and the memory card,the design of a DMA(Direct Memory Access)high speed transmission engine based on PCIe,using the memory mapping mechanism,the kernel memory is mapped to the application space,and introduce no interrupt polling mechanism for hosts and card data into synchronous update,improve the data transmission efficiency.Data packet playback tool to support the playback of three different speed hardware process:playback from the on-chip buffer,playback from RAM(Random Access Memory)Disk and playback from the hard disk.In the control data transmission precision,using FPGA,a token based high accuracy flow control method is proposed,and the relative error of the flow rate is limited at the 10~-55 level.2.A high speed network data generation scheme based on analog data stream is designed.Based on the analysis of the characteristics of data stream,a new method of data packet generation based on stream feature sequence is proposed.The basic idea is to divide the flow into two parts:static characteristics and dynamic characteristics.The two parts can be configured by the extensible configuration interface.A configuration describes the characteristics of the data flow.Using the software to generate a sequence of data streams,and then FPGA generates the corresponding data packets for each stream feature sequence.In order to be compatible with a variety of user protocols,in Baotou,the data set aside a 256 byte protocol description,but also the use of a variety of changes in the field of data flow model.After testing,the proposed scheme can simulate the high speed mixed data traffic,and characterize the characteristics of the network traffic from the other point of view.