Research Of Multipath Transmission Traffic Distribution And Control Technology

With the increase requirements of network bandwidth and the development of network accesstechnology, multipath technology has gained widely concern in recent years. As a major multipathtechnique in transport layer, SCTP and MPTCP have overcome the disadvantages of multipathtechniques in network layer, application layer and link layer. They can effectively collect theinformation on the path to balance the congestion and are applied to aggregate multiple interfaceterminal transmission resources.In order to reduce the time of the failover and improve the network performance, With the NS2simulation platform as the foundation, we design the SCTP failover application scenarios, analysisthe control parameters include the Path Max Retransmission, Retransmission Timeout andHeartbeat time interval, etc., and their effects of failover performance. Results show that theoptimization of control parameters can greatly reduce failure recovery time, improve the end-to-enddelivery performance.The mobility management based on SCTP has been studied for applications over multipleterminals in a heterogeneous network. We propose a scheme of inter-terminal handover with acontinuity of end-to-end connection. In order to make the handover compatible with thespecifications of SCTP association, we adopt the extension of Dynamic Address Reconfigurationand the mechanism of association restarting to realize terminal joining and verification updatingacross terminals. The path switch of SCTP is also utilized to manage the handover. The descriptionof a prototype, which is designed and implemented on the base of Linux and open-source softwarepackages, is also provided for real-time streaming media playback. By experiments over theprototype, our proposal of handover is studied in both feasibility and latency. It is showed thatmulti-media streaming in a LAN environment can be migrated continuously from one terminal toanother within1second. The handover requires no effect of either the media server or networkintermediate systems to premise the pre-established connection unbroken.We have proposed a RTT-Equal Weighted (R-EW) algorithm based on the traditional algorithmand consider RTT which is the main factor influencing the overall transmission performance, wealso consider two factors, one of adjustment coefficient, and the other, balance adjustmentcoefficient. The adjustment factor can be used for occupying fairly the shared resource over a link,and the balanced factor can be used to ensure MPTCP congestion equilibrium among subflows. By verifications over a NS2platform, it shows that R-EW algorithm on the throughput performance issuperior to the Linked Increases algorithm and MPTCP and TCP flows share bottleneck bandwidthfairly on the link.MPTCP packet reorder scheduling algorithm is proposed with RTT based on the analysid ofthe main factors influencing the performances of MPTCP. By estimating the time at the receivingend, we proposed packets reorder scheduling algorithm which is56%higher than Round Robinalgorithm in the simulation environment of MPTCP throughput.