| TCP and SCTP are usually chosen to implement the data transmission with highly reliability, which must transfer data reliably.But both of them ca not meet with the demand of high efficiency and adaptivity in th current network application. SCTP is stream-based protocal, if used in message transmission, it will add delay and decrease utilization. And AIMDalgorithm in TCP reduces the TCP congestion window drastically but fails to recover it to the available bandwidth quickly. Additionally, the unfairness of RTT bias inherent in TCP congestion control also becomes more serious in distributed data intensive applications. As the network bandwidth-delay product(BDP) increases, This RTT bias severely limits the effectiveness of distributed computations based on high- speed wide-area networks.Another widely used protocal in tranport layer is UDP. UDP is a message-based protocal,which used to support application in transfer data between computers.UDP is noneed connection protocal with advantages of high efficiency and loss resource cut.But UDP self has no congestion control mechanism, so these kind application need add congestion control mechanism to realize reliable data transfer.Thus, We design an application protocal based on UDP which is named RUDP.We ananlyse many related articles and essay , research the Reliable Data Transfer technology deeply,design the RUDP software module ,which based on RUDP strucure and WinSocket ,reliaze the reliable and high efficient data communication in distributed system.In this study, firstly,analysed the develop of the Reliable Data Transfer technology, and indicate the problem in the technologies.Then introduce the principle of RUDP, described congestion control and rate control in detail;introduced the structure and logical design of reliable data transfer system based on RUDP. Finally, design RUDP software module accord to the logical design .implement reliable the data transmission, and compare efficiency between TCP and RUDP. |
