Design And Implement Of Stream Control Transmission Protocol Based On P4

Stream control transmission protocol(SCTP)is a kind of transmission layer protocol which is still being popularized.At the beginning of design,the advantages of transmission control protocol(TCP)and user datagram protocol(UDP),such as supports orderly and disordered message mode,has been considered for SCTP.In addition to the congestion management and data loss retransmission of TCP,SCTP also has a unique mechanism of multi host and multi flow,and it also has a natural security feature to prevent denial of service(DOS)attacks.Therefore,SCTP has been used as the main transport layer protocol for many pplications with special requirements for stability and security.If the transport order is taken into account,SCTP is undoubtedly the most appropriate choice.However,SCTP can not cross the existing network address translation(NAT)gateway.At present,SCTP is mostly deployed on the private LAN,and it is difficult to been implemented on the public wide area network.Therefore,this thesis designs a programming protocol independent packet processor(P4)to realize SCTP scheme,the SCTP end-to-end connection is wrapped in UDP message transmission,which is conducive to the development of SCTP public network.The custom way to realize the design of data plane has been used by P4.It is convenient to carry out the programmable configuration by using the protocol independent and device independent features of the language.According to the performance requirements,it can also directly deploy the design to the hardware device through the platform related compiler.The main work of this thesis is to use the programmable data plane to implement the UDP encapsulation SCTP scheme similar to that provided by RFC6951,the SCTP encapsulation and unpacking module has been deployed at the terminal exit.The innovation of this design is that using P4 as the implementation of SCTP so that SCTP protocol can be separated from the kernel protocol stack and implemented on the switching device using the programmable data plane.In this thesis,Software Defined Network(SDN)is used to build network topology,which has passed the test and verification of the second version of behavior model version 2(BMv2)software switch,the protocol specification of SCTP has been basically met.Under the maximum 10 Mbps bandwidth allowed by the test topology,the packet loss rate of UDP message is not more than 1% all the time,which can be satisfied for the needs of normal public network.A feasible scheme for SCTP public network deployment has been provided by this design.It is suitable for the next generation transport layer.The function of SCTP protocol for ordinary UDP message is provided by it to solve the problem of passing through the similar firewall or NAT gateway in the process of using SCTP.By separating the data plane and the control plane,the logic function of this design is independent of the device.With the help of the corresponding back-end compiler,different software or hardware devices can be selected according to the actual needs to meet the needs of different application scenarios.