Research On Multi-Path Transmission Based On MSCTP In Mobile Environments

With the development of wireless communication technology, it is an obvious trend that we can access to Internet using heterogeneous wireless access networks. The multi-path transmission technology use multiple paths to transmit data simultaneously. It aims at improving the network efficiency and end-to-end throughput. The existing multi-path transmission schemes are realized at network layer, transport layer or application layer. However, the existing schemes focus on basic transmission mechanism implementation, while paying little attention on path management and path selection strategies, i.e., lack of support for mobile environments. Therefore, the multi-path transmission technology in mobile environment is one of the important research issues in mobility management.Because of end-to-end control and transmission control mechanism, transport layer is suitable to implement concurrent multi-path transmission. And the key factor is to decouple the congestion control for the whole data transmission with the flow control for each path. In the design of SCTP (Stream Control Transmission protocol), multi-homing is one of the good features, which allowing for multi-interface terminals. In addition, IETF designed the DAR (Dynamic Address Reconfiguration) extension for SCTP, i.e., mobile SCTP(mSCTP), which has mobility supporting ability. Therefore, many schemes select SCTP to implement multi-path transmission.This dissertation mainly focused on the key problems to implement the multi-path transmission based on mSCTP protocol in mobile environments. Based on analysis to the existing schemes, the key problems are proposed: modification of the original transmission mechanisms, path management solution in mobile environment, path selection strategy. Corresponding solutions for these three problems are proposed. In addition, the proposed solutions are implemented in NS-2 network simulation software. Then the simulation scenarios are designed and developed. Simulation results show that this proposed solution can improve the end-to-end throughput of an association and the network efficiency in mobile environment. Finally, we installed and tested the LKSCTP module, and we proposed preliminary design for implementing multi-path transmission based on mSCTP in mobile environment in Linux OS.