Design And Implementation Of A High Performance Protocol Reassembly System Based On SCTP

SCTP is a transport layer network protocol which is defined to compensate for TCP defects.With the continuous promotion and popularization,SCTP has become one of the core protocols in the fields which are sensitive to performance and reliability.More and more vendors'devices are also supporting SCTP.Therefore,SCTP will likely replace TCP and become the main stream transport layer protocol for next-generation IP networks,and the importance of high-performance protocol reassembly is beginning to emerge.Protocol reassembly technology is an important technology in the field of network security,and is also widely used in related fields such as auditing and public opinion monitoring.However,the current protocol reassembly tools have gradually failed to meet the requirements of protocol reassembly under high-speed networks,and the requirements for protocol reassembly of SCTP cannot be met.In order to avoid the impact of packet capture performance on protocol reassembly,this paper designs a SCTP protocol reassembly system based on DPDK.The DPDK is a development kit for fast processing of data packets.It contains multiple drivers and a complete set of libraries for quickly capturing and processing data packets.The system captures the data through the DPDK,and then sends the data to the load balancing module,which is assigned a reassembly thread by the load balancing module,and ensures that all data of the same association is processed by the same reassembly thread.After the reassembly thread receives the data,it performs the association re-aggregation,and finally relocates through the multi-level linked list to the position where the fragment of the data should belong.After the reassembly is completed and the submission condition is satisfied,the user-defined application layer processing function is called.Complete the entire protocol reassembly process.The whole process needs to improve the overall performance as much as possible on the basis of ensuring correctness,so that it can meet the requirements of SCTP protocol reassembly under high-speed network.Finally,through several functional tests for SCTP characteristics,the correctness of the protocol reassembly of the entire system is verified.The performance test results show that the average packet processing speed can reach 1.996Mpps,and the average traffic processing speed can reach 10.27Gbps,which can meet the performance requirements of protocol reassembly under high-speed network.